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Radiological Signs in Chest Medicine
Gamal Rabie Agmy MD FCCP Professor of chest Diseases Assiut university
S Curve of
Golden
When there is a mass
adjacent to a fissure the
fissure takes the shape
of an S The proximal
convexity is due to a
mass and the distal
concavity is due to
atelectasis Note the
shape of the transverse
fissure
This example represents
a RUL mass with
atelectasis
Pulmonary Artery
Overlay Sign
This is the same concept
as a silhouette sign If
you can recognize the
interlobar pulmonary
artery it means that the
mass seen is either in
front of or behind it
This is an example of a
dissecting aneurysm
Achalasia of esophagus
Inhomogeneous cardiac density
Right half more dense than left
Density crossing midline (right black
arrow)
Right sided inlet to outlet shadow
Right para spinal line (left black
arrow)
Barium swallow below Dilated
esophagus
Feeding vessel sign
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
S Curve of
Golden
When there is a mass
adjacent to a fissure the
fissure takes the shape
of an S The proximal
convexity is due to a
mass and the distal
concavity is due to
atelectasis Note the
shape of the transverse
fissure
This example represents
a RUL mass with
atelectasis
Pulmonary Artery
Overlay Sign
This is the same concept
as a silhouette sign If
you can recognize the
interlobar pulmonary
artery it means that the
mass seen is either in
front of or behind it
This is an example of a
dissecting aneurysm
Achalasia of esophagus
Inhomogeneous cardiac density
Right half more dense than left
Density crossing midline (right black
arrow)
Right sided inlet to outlet shadow
Right para spinal line (left black
arrow)
Barium swallow below Dilated
esophagus
Feeding vessel sign
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Pulmonary Artery
Overlay Sign
This is the same concept
as a silhouette sign If
you can recognize the
interlobar pulmonary
artery it means that the
mass seen is either in
front of or behind it
This is an example of a
dissecting aneurysm
Achalasia of esophagus
Inhomogeneous cardiac density
Right half more dense than left
Density crossing midline (right black
arrow)
Right sided inlet to outlet shadow
Right para spinal line (left black
arrow)
Barium swallow below Dilated
esophagus
Feeding vessel sign
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Achalasia of esophagus
Inhomogeneous cardiac density
Right half more dense than left
Density crossing midline (right black
arrow)
Right sided inlet to outlet shadow
Right para spinal line (left black
arrow)
Barium swallow below Dilated
esophagus
Feeding vessel sign
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Feeding vessel sign
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Radiographic Signs of Pneumomediastinum
Subcutaneous emphysema
Thymic sail sign
Pneumoprecardium
Ring around the artery sign
Tubular artery sign
Double bronchial wall sign
Continuous diaphragm sign
Extrapleural sign
Air in the pulmonary ligament
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Incomplete Border Sign
(Pregnant Lady Sign) The incomplete border sign is
useful to depict an
extrapulmonary mass on
chest radiograph
An extrapulmonary mass will
often have a inner well defined
border and an ill-defined outer
margin This can be attributed
to the inner margin being
tangential to the x-ray beam
and has good inherent
contrast with the
adjacent lung On the other
hand the outer margin is
enface or partially enface with
the x-ray beam and merges
with the pleural or chest wall
thus the border is obscured
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Ginkgo leaf sign bull The ginkgo leaf sign is a chest plain radiography
appearance which is seen at extensive subcutaneous
emphysema of the chest wall Air outlines the fibers of
the pectoralis major muscle and creates a branching
pattern that resembles the branching pattern in the
veins of a ginkgo leaf
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Juxtaphrenic peak sign
The juxtaphrenic peak sign refers to the peaked or
tented appearance of a hemidiaphragm which can
occur in the setting of lobar collapse It is caused by
retraction of the lower end of diaphragm at an inferior
accessory fissure (most common) major fissure
or inferior pulmonary ligament It is commonly seen
in upper lobe collapse but may also be seen in middle
lobe collapse
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
CT angiogram Sign
Identification of vessels within an
airless portion of lung on contrast-
enhanced CT
The vessels are prominently seen
against a background of low-
attenuation material
Associated with
bronchoalveolar cell carcinoma
lymphoma
infectious pneumonias
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Fallen Lung Sign
This sign refers to the appearance
of the collapsed lung occurring
with a fractured bronchus
The bronchial fracture results in
the lung to fall away from the
hilum either inferiorly and laterally
in an upright patient or posteriorly
as seen on CT in a supine patient
DD
Pneumothorax causes a lung to
collapse inward toward the hilum
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Luftsichel Sign
bullGerman for sickle of air (luft air sichel
crescent)
bullParamediastinal lucency due to
interposition of lower lobe apex between
mediastinum and shrunken upper lobe
bullOccurs more commonly on the left than in
the right
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Halo Sign
CT shows nodular consolidation associated with a halo of ground-glass
opacity (GGO) in both apices resulting from invasive pulmonary
aspergillosis
This halo represents hemorrhage
When seen in leukemic patients is highly suggestive of the diagnosis of
invasive pulmonary aspergillosis
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
CT Halo Sign
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Reverse Halo Sign
bullCentral ground-glass opacity surrounded
by denser consolidation of crescentic or
ring shape at least 2 mm thick
bullFirst described by Voloudaki in 1996
bullKim in 2003 used the term reverse halo
bullFound to be relatively specific for crypto-
genic organizing pneumonia (COP)
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Reverse Halo Sign
Seen in other conditions
bullWegenerrsquos granulomatosis
bulllymphomatoid granulomatosis
bullparacoccidiodomycosis
bullneoplastic (metastasis)
bullinvasive aspergillosis
bulllipoid pneumonia
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Tree-in-Bud Sign
bull
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Pearl ring sign
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Steeple sign
The steeple sign (also called wine bottle
sign) refers to tapering of the
upper trachea on a frontal chest
radiograph reminiscent of a church
steeple The appearance is suggestive
of croup which should be obvious
clinically A corresponding lateral x-ray
would show narrowing of the subglottic
trachea and ballooning of the
hypopharyn
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Cancer Breast
Larger right breast Inverted nipple
Radiation Fibrosis of
Lung
Right lung smaller
Right hemithorax smaller
Paramediastinal fibrosis
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Mosiac pattern
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Where is the pathology
in the areas with increased density meaning there is ground glass
in the areas with decreased density meaning there is air trapping
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Pathology in black areas
Airtrapping Airway
Disease
Bronchiolitis obliterans (constrictive bronchiolitis) idiopathic connective tissue diseases drug reaction
after transplantation after infection
Hypersensitivity pneumonitis granulomatous inflammation of bronchiolar wall
Sarcoidosis granulomatous inflammation of bronchiolar wall
Asthma Bronchiectasis Airway diseases
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Airway Disease
what you seehelliphellip
In inspiration sharply demarcated areas of seemingly increased
density (normal) and decreased density
demarcation by interlobular septa
In expiration bdquoblack‟ areas remain in volume and density
bdquowhite‟ areas decrease in volume and increase in
density
INCREASE IN CONTRAST
DIFFERENCES
AIRTRAPPING
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Bronchiolitis
obliterans
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Early Sarcoidosis
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Chronic EAA
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Hypersensitivity pneumonitis
Extr Allerg Alveolitis (EAA) HRCT
Morphology
chronic fibrosis
Intra- interlobular septal thickening
Irregular interfaces
Traction bronchiectasis
acute - subacute
acinar (centrilobular) unsharp densities
ground glass (patchy - diffuse)
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Pathology in white Areas
Alveolitis Pneumonitis
Ground glass desquamative intertitial pneumoinia (DIP)
nonspecific interstitial pneumonia (NSIP)
organizing pneumonia
In expiration both areas (white and black) decrease in
volume and increase in density
DECREASE IN CONTRAST
DIFFERENCES
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
DI
P
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Cellular
NSIP
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Mosaic Perfusion
Chronic pulmonary embolism
LOOK FOR
Pulmonary hypertension
idiopathic cardiac disease pulmonary
disease
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
CTEPH =
Chronic thrombembolic
pulmonary hypertension
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Secondary lobule
Basic anatomic unit of pulmonary
structure and function
1-2 cm and is made up of 5-15
pulmonary acini
Supplied by a small bronchiole
(terminal bronchiole) in the
center that is parallelled by the
centrilobular artery
Pulmonary veins and lymphatics
run in the periphery
Two lymphatic systems
central network
peripheral network
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
The terminal bronchiole in the center divides into respiratory bronchiolies with acini that contain alveoli Lymphatics and veins run within the interlobular septa
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Centrilobular area in blue perilymphatic area in yellow
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Raoof S CHEST 2006 129805
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Perilymphatic distribution
Centrilobular distribution
Random distribution
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
ARE NODULES IN CONTACT WITH PLEURA
NO
CENTRILOBULAR
YES
PERILYMPHATIC RANDOM
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Hypersensitivity
pneumonitis
HRCT at the level of the
upper lobes reveals an ldquoill-
defined centrilobular nodular
patternrdquo characterised by
micronodules of ground-
glass opacity that are
diffusely distributed
characteristically in the
centre of the pulmonary
lobules
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
RBILD
HRCT at the level of the upper
lobes exhibits an ldquoill-defined
centrilobular nodular patternrdquo
characterised by micronodules of
ground-glass opacity that are
diffusely distributed
characteristically in the centre of
the pulmonary lobules In this case
the history of smoking favours the
diagnosis of respiratory
bronchiolitis interstitial lung disease
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Miliary TB HRCT at the level of the upper
lobes exhibits a ldquomiliary nodular
patternrdquo characterised by random
micronodules diffusely and
symmetrically distributed within the
lungs having approximately the
same size
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Miliary metastatic disease
HRCT at the level of the upper lobes
shows a ldquomilary nodular patternrdquo
characterised by random and
perilymphatic micronodules diffusely
distributed throughout the lungs that
have a more variable size compared
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Differential diagnosis of a nodular
pattern of interstitial lung disease
SHRIMP Sarcoidosis
Histiocytosis (Langerhan cell
histiocytosis)
Hypersensitivity pneumonitis
Rheumatoid nodules
Infection (mycobacterial fungal viral)
Metastases Miliary TB
Microlithiasis alveolar
Pneumoconioses (silicosis coal
workers berylliosis)
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
DECREASED LUNG
ATTENUATION
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Lung Cysts
Pulmonary fibrosis (Honeycombing)
Lymphangiomyomatosis
Langerhanscell histiocytosis
Lymphocytic Interstitial Pneumonia (LIP)
Differential Diagnosis
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Rough Reticular Fine Reticular
Traction
Bronchiectasis
and
Interface
sign
Honey
combing
UIP UIP or NSIP
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Usual Interstitial Pneumonia UIP
HRCT Findings
Reticular opacities thickened intra- and
interlobular septa
Irregular interfaces
Honey combing and parenchymal distorsion
Ground glass opacities (never prominent)
Basal and subpleural predominance
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Basal and subpleural distribution
UIP
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Lymphangioleiomyomatosis
(LAM)
HRCT Morphology
Thin-walled cysts (2mm - 5cm)
Uniform in size rarely confluent
Homogeneous distribution
Chylous pleural effusion
Lymphadenopathy
in young women
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Lymphangioleiomyomatosis (LAM)
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Tuberous Sclerosis (young man)
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Langerhans Cell Histiocytosis
HRCT Findings
Small peribronchiolar nodules (1-5mm)
Thin-walled cysts (lt 1cm)
Bizarre and confluent
Ground glass opacities
Late signs irreversible parenchymal fibrosis Honey comb lung septal thickening
bronchiectasis
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
1 year later
Peribronchiolar Nodules Cavitating nodules and cysts
Langerhans Cell Histiocytosis
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Langerhans Cell Histiocytosis
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Langerhans Cell Histiozytosis
Key Features
Upper lobe predominance
Combination of cysts and noduli
Characteristic stages
Increased Lung volume
Sparing of costophrenic angle
S
M
O
K
I
N
G
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
after cessation of smoking
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Benign lymphoproliferative
disorder Diffuse interstitial infiltration of
mononuclear cells
Not limited to the air ways as
in follicular Bronchiolitis
LIP
= Lymphocytic Interstitial Pneumonia
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Sjoumlgren LIP
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
LIP
= Lymphocytic Interstitial Pneumonia
Rarely idiopathic
In association with Sjoumlgren‟s syndrome
Immune deficiency syndromes AIDS
Primary biliary cirrhosis
Multicentric Castlemean‟s disease
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Sjoegren disease
Dry eye and dry mouth
Fibrosis bronchitis and bronchiolitis
LIP
Overlap
Sarcoid DMPM MXCT
SLE RA (pleural effusion)
Up to 40 x increased risk for lymphoma (mediastinal
adenopathy) and
2 x times increased risk for neoplasma
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Young woman Dry mouth Smoker
LAM LIP Histiocytosis
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Wegenerbdquos disease
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Rheumatoid Arthritis
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Emphysema
histopathological definition
hellippermanent abnormal enlargement of
airspaces distal to the bronchioles terminales
and
hellipdestruction of the walls of the involved
airspaces
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Centrilobular Emphysema
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Panlobular Emphysema
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
CLE and PLE in one Patient
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Fibrosis and Emphysema
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
LAM Emphysema Fibrosis
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
LCH Emphysema
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Fibrosis Emphysema
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Emphysema
Emphysema typically presents as
areas of low attenuation without
visible walls as a result of
parenchymal destruction
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
EMPHYSEMA
Permanent abnormal enlargement of air
spaces distal to the terminal bronchiole
and accompanied by the destruction of
the walls of the involved air spaces
112
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Centrilobular emphysema
Most common type
Irreversible destruction of alveolar
walls in the centrilobular portion of the
lobule
Upper lobe predominance and
uneven distribution
Strongly associated with smoking
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Centrilobular (proximal or
centriacinar) emphysema
Found most commonly in the upper lobes
Manifests as multiple small areas of low attenuation without a
perceptible wall producing a punched-out appearance
Often the centrilobular artery is visible within the
centre of these lucencies
114
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Centrilobular emphysema due to smoking The periphery of
the lung is spared (blue arrows) Centrilobular artery (yellow
arrows) is seen in the center of the hypodense area
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency but
also seen in smokers with advanced
emphysema
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
PANLOBULAR EMPHYSEMA
Affects the entire secondary pulmonary
lobule and is more pronounced in the lower
zones
Complete destruction of the entire pulmonary
lobule
Results in an overall decrease in lung
attenuation and a reduction in size of
pulmonary vessels
117
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
PANLOBULAR EMPHYSEMA
118
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Panlobular emphysema
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Paraseptal (distal acinar)
emphysema
Affects the peripheral parts of
the secondary pulmonary lobule
Produces subpleural lucencies
120
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Paraseptal emphysema
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Cystic lung disease
Lung cysts are defined as radiolucent areas with a
wall thickness of less than 4mm
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Langerhans cell histiocytosis
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Lymphangiomyomatosis complicated by pneumothorax
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Bronchiectasis
Bronchiectasis is defined as localized bronchial
dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of airways
in the peripheral lung
mucus retention in the broncial lumen
associated atelectasis and sometimes air
trapping
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
ABPA glove-finger shadow due to mucoid impaction in central
bronchiectasis in a patient with asthma
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Signet-Ring Sign
A signet-ring sign represents an axial cut of a dilated bronchus
(ring) with its accompanying small artery (signet)
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Tram Tracks
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Bronchial dilation with lack of tapering
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
HONEYCOMBING
Defined as - small cystic spaces with
irregularly thickened walls composed of
fibrous tissue
Predominate in the peripheral and subpleural
lung regions
Subpleural honeycomb cysts typically occur
in several contiguous layers DD- paraseptal
emphysema in which subpleural cysts usually
occur in a single layer
Indicates the presence of ldquoEND stagerdquo
disease regardless of the cause
131
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Honeycombing
Honeycombing is defined by the presence of small cystic
spaces with irregularly thickened walls composed of
fibrous tissue
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Causes
Lower lobe predominance
1 UIP or interstitial fibrosis
2 Connective tissue disorders
3 Asbestosis
4 Drug induced
5 NSIP (rare)
Upper lobe predominance
1 End stage sarcodosis
2 Radiation
3 Hypersensitivity Pneumonitis
4Silicosis
4 End stage ARDS
133
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Honeycombing
HRCT showing
subpleural
broncheolectasis
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Honeycombing and traction bronchiectasis in UIP
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Typical UIP with honeycombing and traction
bronchiectasis in a patient with idiopathic
pulmonary fibrosis (IPF)
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Inconsistent with UIP
pattern (any one of
seven features)
Possible UIP
pattern (all
three features)
UIP pattern (all
four features)
bullUpper or mid lung
predominance
bullperibronchovascular
predominance
bullextensive ground glass abnormality (extent gt
reticular abnormality)
bullprofuse micronodules
(bilateral predominantly
upper lobes) bulldiscrete cysts (multiple
bilateral away from areas of
honeycombing)
bulldiffuse mosaic
attenuationair trapping (bilateral in three or more
lobes)
bullsubpleural basal
predominance
bullreticular abnormality
bullAbsence of features listed as inconsistent
with UIP pattern
bullsubpleural basal
predominance
bullreticular abnormality
bullhoneycombing with
or without traction
bronchiectasis
bullAbsence of features
listed as inconsistent
with UIP pattern
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Hydrostatic pulmonary
oedema
ldquoseptal patternrdquo characterised by
thickened smoothly interlobular
septae in the right parahilar area
Right pleural effusion is also seen
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure
Lymphangitic carcinomatosis
HRCT of the right lung shows a
ldquoseptal patternrdquo characterised by
diffuse nodular thickening of the
interlobular septae and the right
major fissure