Interpretting Neonatal Xrays [Click Enable Macros]

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Interpreting Neonatal X-RaysA Clinician's Perspective

November 2005 EXIT

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David W. Cartwright

Director of Neonatology

Royal Women's Hospital, Brisbane

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2 Catheters and Tubes

1 Potentially Confusing Shadows

3 Some Lung Conditions

Some Cardiac Conditions4

Interpreting Neonatal X-RaysA Clinician's Perspective

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Pneumothorax and other air leaks5

Abdominal Conditions6

Intraventricular Haemorrhage / PVL7

8 Complications of ventilation

9 Osteopaenia of prematurity 3-13

91-104

105-153

154-199

200-241

242-263

264-278

POTENTIALLY CONFUSING SHADOWS Follow this group through sequentially by using the left mouse

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Main Menu

1 Thymus

2 Incubator Shadows

3 Sternal segments

4 'Noah' ECG electrode

5 Umbilical Stump

Neonatal Chest X-Rays

Always look at the:-

• Lungs

• Airways

• Mediastinum

• Bones

The THYMUS may be very variable in size and appearance. These 4 radiographs all show normal thymus.

Thymus meets right heart border

Right lobe of thymus larger than left, and sitting on horizontal fissure

A bend in the perspex of an infant incubator will bend the x-rays passing through it - here it appears as a line of lesser density (has bent the x-rays away from it) passing down the left side of the baby, and bending away at the top and bottom, also distorting the view of the left lower arm and hand. The baby should be positioned in the bed so that this does not happen.

Some neonatal incubators have a solid metal bar in a frame above them used to support an overhead shelf. If this is included in the field being x-rayed it will totally absorb all x-rays and produce a very white linear shadow. This radiograph was taken to view the position of a UA line and an ET tube. Both of these are not visible because of the metal bar shadow.

The hole in the top of an infant incubator may appear as a dark round shadow, here in the left upper quadrant of the abdomen. The infant should be positioned to avoid this, as this shadow can at times be misinterpreted, although it is more symmetrically round than any anatomical structure is likely to be.

In a double-walled incubator, the holes in each of the walls are of different size, the one in the interior wall being the larger, and produce a double-ringed shadow as seen above in the lower left abdominal quadrant.

Segments of the sternum visible on a rotated CXR can be confusing. Up to five ossification centres of sternebrae may be seen, some of them sometimes paired (below,

right), especially those of the first (manubrium sternae).

N-G Tube

UA Line

Broken lines outline the Noah single lead electrode chest component. White arrows point to the attached leads - the lower one going to the connection with the monitor, and the upper to the second electrode component on the upper arm.

Artifactual shadow produced by a 'Noah' single lead ECG electrode (see photograph at right), simulating a right upper lobe collapse. While these leads are essentially radiolucent, they can produce sufficient grey shadowing in a small baby to be confusing.

UV Line

UA Line

N-G Tube

Further example of artifactual shadow from a 'Noah' single lead ECG electrode, simulating a right lower lobe consolidation.

Broken lines outline the Noah single lead electrode chest component. White arrows point to the attached leads - the lower one going to the connection with the monitor, and the upper to the second electrode component on the upper arm.

Identify the 'Noah' lead shadows in these x-rays

'Noah' electrode

Umbilical stump

Skin temperature probe

Double-lumen UV line'Noah'

electrode lead

CATHETERS AND TUBES Follow this group through sequentially by using the left mouse

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Main Menu

1 UA and UV Lines

2 Endotracheal Tubes

3 Central Venous Lines (Silastic)

4 Nasogastric Tube

5 Graseby Capsule

An umbilical arterial catheter passes into the pelvis before tracking upwards into the aorta - travelling by the umbilical artery, the internal iliac artery and the common iliac artery

UMBILICAL CATHETERS:

The white shadow running across the tip of the umbilical venous catheter is the electrical connection of a 'Noah' single lead ECG electrode, seen side-on, but flattening out to be less readily visible when viewed flat-on as it passes out across the right chest wall.

An umbilical venous catheter passes directly from the umbilicus towards the heart, travelling via the umbilical vein, ductus venosus and inferior vena cava to the right atrium. The fresh umbilical stump in this newly-born baby appears as a white 'blob' just above the pelvis

Edge of Noah electrode

UMBILICAL VENOUS CATHETER:

The umbilical venous catheter in this patient has been inserted further than intended, and passes through the inter-atrial septum into the left atrium, and out into a pulmonary vein (you get very good blood gases from such a catheter, even in a patient with significant pulmonary hypertension).____________________________________

Best position for the tip of a UV catheter is at the level of the diaphragm (below), just where the IVC enters the right atrium.

Note the course of the umbilical venous catheter in lateral projection, initially passing superiorly just under the skin, then passing posteriorly (travelling in the inferior edge of the falciform ligament) to gain entrance to the IVC and right atrium.

UMBILICAL ARTERIAL CATHETER:

This umbilical arterial catheter has passed up the aorta and into the left subclavian artery. The tips of the fingers on the left hand were cyanosed.

An umbilical arterial catheter which has travelled down the femoral artery - this is quite unusual

This umbilical arterial catheter (above) has curled back on itself in the aorta. Frequently, if another catheter is passed down the same vessel, it will pass without curling, and the original one can then be removed. When inserting a catheter which behaves this way, one usually experiences some resistance at 5-6 cm into the insertion, then feels it 'give way' and advance. Presumably the angle between the umbilical and internal iliac arteries is greater than usual and the catheter does not passreadily around that bend.

This endotracheal tube has been advanced too far, with its tip (green arrow) in the right mainstem bronchus, well beyond the take-off of the left mainstem bronchus (black arrows). There is resultant collapse of the left lung and right upper lobe through lack of aeration (the right upper lobe bronchus comes off the right mainstem bronchus just below the carina). Note also that the baby was rotated to the right when this radiograph was taken, as evidenced by the asymmetrical view of clavicles and rib ends.

The endotracheal tube normally runs on the same side of the vertebral bodies as the direction in which the head is turned (note the tip of the mandible in the top left of this radiograph, head turned to the baby's right). If the ETT is not on the same side of the vertebral bodies as the mandible, it is probably in the oesophagus

Another endotracheal tube that has been advanced too far, with no collapse of any lung segments at this time. Frequently, however, after such a tube has been pulled back, there will have been sufficient irritation of the opening of the right upper lobe bronchus to cause oedema of that bronchus and complete right upper lobe collapse.

Note the radio-opaque 'blue line' of a Portex ETT runs along the long side of the curve of the tube. It always reaches the bevel at the distal end of the tube at a point one-half way along the bevel. Some other brands of ETT are not as consistent in this respect between tubes.

Uncommonly, an endotracheal tube advanced too far will travel down the left main stem bronchus. In this instance, there is resultant hyperinflation of the left lung which could easily be misinterpreted as a pneumothorax. The secret in management is to pull the tube back and reassess before draining the 'pneumothorax'.

Note the head here is turned to the right, and the endotracheal tube travels to the right of the vertebral bodies. It is much more informative to take these radiographs with the head turned rather than in the midline position, and more so if the upper alveolar margin is included in the field to allow one to see the position of the ETT taping and assess the need to retape the tube. Sometimes the taping has simply become loose and ‘sloppy’, and needs retaping firmly in its original position to correctly position the tip, rather than shifting the taped position which may move the tip further than you intended.

Complete right upper lobe collapse occurring after removal of an endotracheal tube which has previously been positioned too low. Note the horizontal fissure is pulled upwards by the lobar collapse, and the trachea is pulled to the right. The asymmetry of the anterior rib ends indicates that the baby was rotated to the left when this radiograph was taken.

The upper lobe bronchus takes off from the right main stem bronchus just below the carina, and travels postero-superiorly, before further branching. Thus positioning for draining this bronchus is 1/4 off prone, right side up, with slight upwards head tilt.

Malpositioned endotracheal tube (oesophageal intubation). The mandible is to the right, and the trachea can be seen to the right of the vertebral bodies (yellow arrow), while the endotracheal tube is to the left, and the oesophagus is filled with gas (black arrows). When listening to the air entry in this situation, an unusual harsh moist sound is heard during inspiration. Another clinical sign to look for when intubating a baby is the appearance of a 'mist' of humidity in the ETT during expiration - this does not occur in an oesophageal intubation.

Air bronchograms are visible in both upper lobes. A slightly more lordotic projection than usual gives an unusual appearance to the upper 5 ribs on the left, and upper 4 on the right - the anterior rib ends directly overly the posterior bodies of the ribs, rather than being seen inferiorly tothem as in the more usual projection. There is also some rotation of the baby to the right.

Silastic Central Venous Lines are inserted via a peripheral vein, with the intent of having the tip of the line in the top of the right atrium, or in the SVC. The line shown here is not radio-opaque, and is injected with a radio-opaque dye (e.g. Isovue 300) while being x-rayed. The above two lines are respectively in the Superior Vena Cava and low in the Right Atrium. In both there is a small blush of dye exiting the line tip. It is useful when injecting such lines to be still injecting while the x-ray is taken, to be surethe tip is illustrated this way. The one on the right should be pulled back. It is on or very close to the tricuspid valve.

This silastic ‘Central Venous Line’ (red arrows) travels down behind the heart, to have its tip at the centre of the T12 vertebral body. It has been inadvertently inserted into the left brachial artery, and travels down the descending aorta. There is no vein that travels this path.The yellow arrows point to the electrical leads of a 'Noah' single-lead ECG electrode - the main part of the electrode can be clearly seen, making the lung fields look just a little more dense where it overlies them.

Both of the lines shown here also travel into the aorta - to the left of the vertebrae

The silastic Central Venous Line at right comes up the left cephalic vein, but then travels back down the axillary vein, and its tip (red arrow) is just at the lateral edge of the radiograph. More dye than usual has been injected, and it is streaming back up the axillary vein, across into the subclavian vein then the innominate vein into the SVC and Right Atrium.

The line below has its tip in the cephalic vein just before it joins the axillary vein to become the subclavian vein, with dye streaming from it down into the SVC. It is not uncommon for catheters coming up the cephalic vein to have difficulty negotiating into the subclavian vein. They do not last well in this position. It is best when possible to insert these catheters into the medial veins at the elbow, whence they pass into the basilic/axillary system rather than the cephalic.

The angle shown here between the cephalic vein and the subclavian vein illustrates why it is often difficult to pass a catheter from the cephalic vein into the SVC (dye injected into cephalic vein catheter)

Cephalic veinSubclavian vein

The tip of this CVL has found its way to a lateral chest wall vein. Dye from the injection has run along two intercostal veins on the left into the hemiazygos vein which clearly interconnects with the azygos vein on the right.

This baby was known to have a Left SVC draining into the coronary sinus. Her CVL passes from the left arm down the L SVC, into the coronary sinus, and then into the Right Atrium, and probably out

into the R SVC.

The tips of these CVLs lie in the ascending lumbar vein, a branch of the common iliac vein, and the dye tracks upwards to the side of the vertebral column, with some crossing across the vertebral column in the radiograph on the left into the subdural venous plexus. These veins eventually join into the hemiazygos on the left, and the azygos on the right. Catheters left in the ascending lumbar vein have been associated with hyperglycorrhachia, lower limb myoclonus, permanent paraplegia and death from leakage of parenteral nutrition solutions into the subarachnoid space. If a ‘radio-opaque’ catheter was used and not injected, you would not know it was in this vein - it would appear to be in the IVC.

This naso-gastric tube has passed out of the stomach into the first part of the duodenum. The tip of the dual-lumen UV catheter lies in the region of the ductus venosus.

Capsule of Graseby monitor

Naso-gastric tube

The circular shadow overlying the stomach (white arrows) is the pneumatic sensor capsule of a Graseby Respiration Monitor, and the tubular shadow running upwards from it the hollow tubing which transmits pressure changes from the capsule to the monitor itself. In this baby, there is the tip of the naso-gastric tube within the stomach also and appearing to be within the Graseby sensor. Overlying the liver, there is a vague circular shadow (yellow arrows) which represents the edges of a reflecting cushioned adhesive pad sometimes used to stick the temperatureprobe onto the skin, especially when an overhead warmer is being used.

Tubing of Graseby monitor

SOME LUNG CONDITIONS Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to one of the slides as listed below by a left-mouse-button click on the number beside the desired slide description. A similar click on the 'Return' button ( ) in the bottom right

corner of any slide in this group will bring you back to this menu.Most topics have more than one slide - move sequentially once a topic is

opened e.g. HMD has 4 slides, RFLF has 6 slides.

Main Menu

2 RFLF

3 Pneumonia

4Pulmonary Haemorrhage

5Meconium Aspiration

6 Diaphragmatic Hernia

7Oesophageal Atresia

8Cystic AdenomatoidMalformation of Lung

9Congenital LobarEmphysema

10Oesophageal Duplication Cyst

11Pleural Effusions Neuroblastoma

12 Pleural Effusions Idiopathic

13 Chest Wall Hamartoma

14 Pulmonary Hypoplasia

15 Chronic Lung Disease

16 Rib Fractures

Hyaline Membrane DiseaseFeatures are:-(1) Fine granular ('ground-glass') pattern through all lung fields, homogenously distributed.(2) Lack of definition of heart and mediastinum, due to the extreme density of the lungs.(3) Air bronchograms outside the cardiac borders – gas in air spaces contrasts against lack of gas in alveoli.(4) A small amount of fluid in the horizontal fissure of the R lung can be seen. Small pleural effusions (not seen here) are uncommon, but are not inconsistent with HMD.(5) There is gas in the oesophagus, seen between the tracheal bifurcation and the abdomen.(6) Two lines crossing the L hemidiaphragm lateral to the heart are artefact, probably skin folds.

The appearances of the rib ends and clavicles indicate that this baby is very slightly rotated to the right.

Oedema fluid

Hyaline membrane

Thick alveolar septa

Newborn lung with HMD

Thin alveolar septa

Normal mature lung

The contrast in lung architectureseen here explains why, when a newborn lung, particularly one with HMD, collapses with a pneumothorax, it still takes up considerable intrathoracic volume.

Hyaline membrane disease (surfactant deficiency, HMD) is characterised by a homogeneous 'ground glass' appearance caused by collapsed alveoli, with gas in airways visible as 'air bronchograms' passing through it (black arrows above). The bronchograms within the cardiac shadow (green arrows above) are normally seen (even without lung disease) as gas in airways contrasts against the dense blood and tissue of the heart.

Note the right main stem bronchus is much more vertical than the left.

'White-out' of severe HMD, with air bronchograms present. Note the lungs are so dense that the right heart border cannot be discerned at all, and the left only vaguely.

Less severe HMD in a non-ventilated baby. Note the air bronchograms in the right upper lobe, and the general homogeneous greyness of the lung fields (‘ground glass’ appearance).

Retained Fetal Lung Fluid (RFLF) has many radiological appearances, mostly characterised by asymmetry within and between lungs, frequently worse on the right than the left, overdistension, and streaky parenchymal markings. Pleural effusions may be seen (not evident in the initial film on the left above, but a small one is present at the right base in the second film on the right above). Rapid clearing is characteristic (12 hours between above two radiographs), as is noted also in the clinical illness, which usually has an oxygen requirement for less than 24 hours. The fetal lung is a secretory organ, and fetal lung fluid is present at a volume of 30mls/kg in fetal life. It is normally reabsorbed during labour under the influence of catecholamines, to be at a volume of only 5-7mls/Kg at the end of labour. In situations of no labour such as elective Caesarean Section, or of very short labour, this reabsorption does not occur or may be incomplete, leaving a large volume of fluid to be coughed up by the fetus, and/or absorbed via pulmonary veins and lymphatics, giving the radiological appearances above. The ‘thoracic squeeze’ of vaginal delivery described in some textscontributes little to the removal of fetal lung liquid.

Birth 12 hours

Retained Fetal Lung Fluid

An early radiograph of an infant with retained fetal lung fluid. The main features to note here are (i) an asymmetrical streaky infiltrate through the lung fields, worse on the right, and radiating out from the hilum, (ii) bilateral basal pleural effusions, and (iii) an excessive amount of fluid present in the horizontal fissure on the right.

The radiograph would be expected to be almost normal within 24hours. One cannot differentiate this radiographic appearance from infection, early lymphatic obstruction, or early obstructed anomalous pulmonary venous drainage.

Progression of Retained Fetal Lung FluidA series of 3 xrays represents the progression of retained fetal lung fluid in a 38 week infant delivered by elective Caesarean section. In the 1 hour film, note firstly the asymmetry of the changes in the lung fields both between the R and L lungs and within each lung field, with the worst changes being present on the right, typically. There is a small pleural effusion at the L base and a somewhat larger one at the R base. Most of the fluid in the R lung field appears to be in alveoli and has a fluffy appearance. In the L lung field there are some streaky changes suggesting fluid is in the interstitium.By 12 hours there has been substantial clearing of the previous changes. The pleural effusions cannot be seen at either base and much of the fluid in the R lung field has disappeared.

By 36 hours of age the lung fields in this infant with retained fetal lung fluid (see previous slide) from birth are virtually normal.

Further example of Retained Fetal Lung Fluid, with flattening of the diaphragms from overdistension present.

Two further examples of RFLF showing rapid clearing in 12 hours - the radiographs to the right were each taken approximately 12 hours after those to the left above.

These radiographs of babies with Group B Streptococcal pneumonia could easily be interpreted as RFLF. The difference is in the clinical presentation and condition of the baby. The baby with RFLF usually looks well, is well perfused and in some but not great respiratory distress with an oxygen requirement of 30-40%. The baby with congenital infection is usually poorly perfused, exhibits significant respiratory distress, and often has a high oxygen requirement. It is safest practice to treat all babies exhibiting respiratory distress with antibiotics, especially those born after any form of labour or after rupture of membranes. This organism can cross intact membranes, so the presence of intact membranes does not guarantee freedom from infection.

THERE IS NO RADIOLOGICAL APPEARANCE THAT CAN DEFINITIVELY BE DIAGNOSED AS CONGENITAL PNEUMONIA, NOR ANY THAT CAN EXCLUDE THAT DIAGNOSIS.

Three further examples of the variable appearance of congenital pneumonia with Group B Streptococcus

Staphylococcal (Staph aureus) pneumonia typically has cystic pulmonary complications and pneumothoraces. This is almost exclusively an acquired infection. While I have seen a number of babies infected with S aureus from birth, I have never seen ‘typical’ Staphylococcal pneumonia in that circumstance.

This infant of 28 weeks gestational age had Hyaline Membrane Disease which had responded well to exogenous surfactant therapy, and was on minimal ventilation in 21% oxygen at left. The radiograph at right was taken after a sudden deterioration marked by the aspiration of a large amount of blood from the endotracheal tube. This PULMONARY HAEMORRHAGE resulted in the need for 100% oxygen, high frequency ventilation and nitric oxide administration. Note the density, in the right lung field particularly, with air bronchograms present as the gas in airways is contrasted against blood in the alveoli. The heart is also increased in size in the radiograph at right, and there were clinical signs of patent ductus arteriosus, which often results in pulmonary haemorrhage in these circumstances.

MECONIUM ASPIRATION appears as a patchy infiltrate asymmetrically distributed throughout the lung fields, with small areas of collapse and hyperinflation. There is frequently generalised hyperinflation produced by gas trapping because of increased airways resistance. Meconium passed before birth is usually sterile, but is a good medium for growth of micro-organisms, so antibiotics should always be administered.

Two further examples of MECONIUM ASPIRATION. The one on the left has a small right basal pleural effusion (and perhaps an even smaller left one), which is not inconsistent with the diagnosis of meconium aspiration without infection. This radiograph also has a skin fold passing upwards in the lateral portion of the left lung field. Meconium aspiration occurs virtually exclusively in relatively mature babies - illustrated by the presence of the proximal humeral epiphysis (red arrow) and that of the coracoid process of the scapula (yellow arrow) in the radiograph at right above.

Meconium Aspiration in a Mature Infant

The radiological features are of extensive patchy atelectasis and

hyperinflation.

(Did you look closely at the bones in the radiograph on the right of the previous slide and note the 13 pairs of ribs, and 'butterfly' vertebra at C7?)

MECONIUM ASPIRATION with streaky patchy collapse, particularly in the right upper lobe. (Proximal humeral epiphysis again seen).

Further example of severe MECONIUM ASPIRATION in an infant born at home. Patchy collapse is seen in many areas of the lung, particularly the lingula and both lower lobes.

Later occurrence of R pneumothorax in the same infant as shown in the previous slide. The upper, middle and lower lobes can all be clearly seen surrounded by gas. The mediastinum is pushed well over to the left, and there is herniation of R pleura anteriorly above the heart to the left.The right hemi-diaphragm is lower than the left, and flattened.

Left congenital diaphragmatic hernia - note the paucity of abdominal gas, and the multiple bowel gas shadows present in the left hemithorax, causing the heart and mediastinum to be pushed over to the right.

This condition is now most often diagnosed antenatally, but should be suspected whenever a baby is deteriorating in the first few minutes after birth, despite adequate resuscitation measures. A quick listen to the chest to check which side the heart sounds are best heard on is helpful in making the diagnosis clinically, as >80% of these lesions are left sided, with the heart pushed well to the right. It is uncommon to hear bowel sounds in the left chest, as described in some texts, but clinically one may appreciate the ‘scaphoid abdomen’.

This may be less readily recognisable as a left diaphragmatic hernia because gas has reached the stomach only. The oesophagus is gas filled at the time of taking this radiograph, and can be seen bowed into the right hemithorax, with a 'naso-gastric' tube within it, but not reaching the stomach. The heart is not clearly outlined, but is in the right hemithorax. The dense shadowing in the left hemithorax is fluid-filled bowel.

Right Diaphragmatic Hernia (An uncommon occurrence)The baby had been intubated soon after delivery and paralysed early, resulting in no swallowed gas reaching the bowel in the R chest.

Following repair , note that the heart and mediastinal structures remain well over in the L chest. The oesophagus is a little more normal in position, outlined in its course here by the nasogastric tube.The R lung is a very small nubbin to the right of the vertebral column at T5/6 level. The R hemidiaphragm has been considerably flattened by the repair procedure.

N-G Tube

Further examples of diaphragmatic hernia - Left-sided, above, with heart pushed into the right chest, oesophagus deviated to the right (see the course of the n-g tube), and gas-filled bowel in the left chest. At right is a right-sided diaphragmatic hernia

After surgical repair of a left diaphragmatic hernia, the left lung remnant is visible in the left hemithorax, the left hemidiaphragm may be quite flattened by being pulled tight to close the defect, and the mediastinum will stay deviated to the right for some days.

In the few days after surgical repair, the left hemithorax will fill with fluid as a transudate 'third space' fluid loss. The left lung is visible within this fluid-filled left hemithorax.

This baby presented for outpatient review and was noticed to be tachypnoeic. CXR showed the presence of gas bubbles within the cardiac shadow. Lateral view at right shows bowel gas tracking up anteriorly - a foramen of Morgagni hernia which was repaired with excellent result.

An x-ray taken for minor respiratory signs in the newborn period revealed this tent shaped shadow on the right hemi-diaphragm (there may be a small bump on the L as well).This is a diaphragmatic eventration and such a lesion of this size would normally be expected to be asymptomatic.This lesion did not change in size over a period of observation and the infant was discharged home.He later died of a sudden unexpected death event, which we presume to be unrelated to the diaphragmatic eventration.

This infant, born in a peripheral hospital, developed respiratory distress soon after delivery.

The radiograph was confusing.The accompanying diagram (next slide) illustrates the structures that are visible here.

Diagrammatic representation of an infant with central diaphragmatic eventration (previous slide).There is a large central defect in the diaphragm between points A and B, with herniation of the L lobe of the liver through the defect into the R side of the chest and herniation of stomach and small bowel centrally. These together have pushed the heart posteriorly and to the L resulting in only a very small section of L lung visible inferior and lateral to the cardiac shadow.

This infant had a large central tendon defect in the diaphragm, allowing diaphragmatic eventration. It was successfully repaired.

Lateral film of the infant (previous 2 slides) with a central diaphragmatic eventration. One can see here that there are bowel gas shadows both anteriorly and posteriorly above the level of the diaphragm.

OESOPHAGEAL ATRESIA WITH TRACHEO-OESOPHAGEAL FISTULA: The black shadow in the upper thoracic region of the A-P radiograph at left (green arrows in central smaller insert) represents a dilated blind ending oesophageal pouch. The baby was probably fortuitously swallowing as this radiograph was taken. If this condition is suspected, it is best to insert a LARGE (=>8 FG, preferably 10FG) tube into the oesophageal pouch - you have made the diagnosis when you feel it stop at around 10cm from the mouth - and inject 20 mls of air quickly as the x-ray exposure is made. You should also ensure the abdomen is included in the field - the presence of gas in the stomach indicates that a tracheo-oesophageal fistula is present. Note also the rib and vertebral anomalies above - 13 pairs of ribs, bifid L4 vertebral body and resultant scoliosis, partially joined ribs on right (red arrow in insert), and butterfly vertebral body at T1. These are common associations with oesophageal atresia (VATER or VACTERL association).

This baby also has oesophageal atresia with tracheo-oesophageal fistula, although the upper oesophageal pouch is not clearly seen in this radiograph (it has not been injected with air as suggested). There are a number of vertebral anomalies present in the upper thoracic region, and some poorly formed ribs (2 & 3) on the right. There are 6 lumbar vertebrae.The asymmetric patchy right lung infiltrate may be due to aspiration of pharyngeal contents unable to be swallowed because of the atretic oesophagus.The absence of gas beyond the stomach suggests the presence of duodenal atresia also. The stomach and proximal duodenum are not as dilated as they usually are when duodenal atresia occurs without oesophageal atresia as the fetus has not been able to fill and distend them with swallowed amniotic fluid.This baby also had anal atresia - both this and duodenal atresia are known associations with oesophageal atresia. Whenever you see a baby with oesophageal atresia, look at the anus carefully, and conversely whenever you see a baby with anal atresia, examine carefully for oesophageal atresia (pass a large naso/oro-gastric tube).

When significant lung disease co-exists with tracheo-oesophageal fistula, the need for assisted ventilation may result in distension of the stomach via the fistula rather than lung inflation as desired. This can result in such gross overdistension of the stomach that gastric rupture occurs with resultant massive pneumoperitoneum as illustrated here. The only effective treatment is to operatively tie the fistula. The baby illustrated here was poorly oxygenated and failing ventilatory management until the fistula was surgically tied. There is a drain in the peritoneal cavity to attempt to relieve abdominal distension, but this did not improve ventilation.

Improvement was immediate and dramatic following fistula ligation, allowing surgical repair of the oesophagus to proceed.

Note there is an endotracheal tube in the trachea, and a Replogle tube in the upper oesophageal pouch - two small gaps in its radiopaque line can be seen, corresponding to its two side holes, one for continuous suction and the other to allow air in and irrigation as required.

CONGENITAL CYSTIC ADENOMATOID MALFORMATION of lung presenting as partially fluid-filled lesions of the right middle lobe at birth.

Note the two partially fluid-filled cysts in the centre of the lesion (fluid levels in lateral radiograph - a ‘shoot-through’ lateral with the baby lying supine).

'CCAM' (Congenital Cystic Adenomatoid Malformation [of lung]) of right middle lobe at birth as in previous slide. Note the partially fluid-filled cyst in the centre of the lesion and its fluid level in lateral radiograph. The fluid has reabsorbed by the second day (below and next slide).

By 2 days, the fluid has reabsorbed, and multiple gas-filled cysts are evident. The trachea and mediastinum are pushed over to the left, and there is some herniation of right lung across the midline above the heart. Abnormal airways leading to these cysts behave in a 'ball-valve' fashion allowing gas in during inspiration, but not allowing free expiration.

Lying right side down restricts the movement of gas into the right lung, and the gas in the overdistended cysts reabsorbs. The mediastinum is now more central, and there is more left lung visible.

After lobectomy, the left lung and the other segments of the right lung fully expand.

This cystic adenomatoid malformation of the lung (right upper lobe) was fluid-filled at birth, and did not ever become gas-filled.

An antenatal diagnosis, on the basis of ultrasound findings, of a R chest tumour had been made on this infant. This radiograph at 1 hour of age shows the mass, with some gas shadows within it. The infant needed assisted ventilation (ETT in situ) and there is mediastinal shift to the left. Note the liver shadow is normal and all of the bowel gas appeared to be in the abdominal cavity.A cystic adenomatoid malformation of the R lung was operatively removed and the infant made a good and complete recovery.

Take a careful look at what you can see here before moving to the next slide.

Just as in later life the lesion of CONGENITAL LOBAR EMPHYSEMA allows some air entry, but incomplete exit, in utero and in immediate postnatal life the affected lobe/s are distended with lung fluid which is produced in the lung and is unable to escape freely. In these two images, the fluid filled lateral segment of the right middle lobe at birth becomes an expanding gas filled congenital lobar emphysema after reabsorption of lung fluid. The upper lobe and lower lobe are compressed. The left upper lobe bronchus is compressed by abnormal pulmonary arteries, and has remained collapsed.

Further illustration of the evolution of right middle lobe congenital lobar emphysema - progressing from fluid filled at birth to an expanding gas filled lesion, compressing other lung segments (right).

Radiograph taken at 45 mins of age in an infant with respiratory distress following delivery by Caesarean section. There is very poor aeration of the left lung fields, with airways visible in the L upper zones. In the inferomedial angle of the L lung, some ‘squashed’ lung tissue can be seen – better illustrated in later films.The trachea is well to the R of the vertebral column, and the heart is pushed into the right chest.A nasogastric tube in the oesophagus bows to the R in mid thorax (the tip of this tube does not quite enter the stomach – it is at the L inferior margin of the body of L1).There is some flattening of the R hemidiaphragm indicating compensatory hyperinflation of the R lung.

Radiograph at 48 hours of age of the infant from the previous slide.

Fluid from the L upper lobe has cleared, being replaced with gas. The compressed segments of L lung infero-medially can now be more clearly seen. The pathology is more obviously a congenital lobar emphysema of the L upper lobe.The mediastinal shift is about the same as it was in the 45 min film. The following day the mediastinal shift was worse and the LUL was surgically excised, with expansion of the remainder of the L lung to fill the L hemithorax.

Evolution of right upper lobe congenital lobar emphysema - progressing from fluid-filled at birth (above) to an expanding gas-filled lesion at 12 days (top right), compressing middle and lower lobe lung segments.

This non-aerated mass in the right chest cannot really be diagnosed on this radiograph. It was an oesophageal duplication cyst, removed surgically.

The mass in the right lower thorax was an enteric duplication cyst.

This right chest mass was also an enteric duplication cyst. Note the 4th thoracic butterfly vertebra, heart pushed over to left, left sacral dysgenesis – there was a tethered spinal cord on ultrasound examination

Bilateral pleural effusions (note rotation of the baby to the right when the radiograph was taken). The horizontal and oblique fissures of the lung are visible on the right. There is an endotracheal tube present which is well to the left of the vertebral bodies, indicating that the upper mediastinum is pushed to the left (the trachea would be expected to appear to the right of the midline when there is right-ward rotation of the baby). See next slide.

'Rat-tail' obstructed trachea

L mainstem bronchus is more vertical than usual

After removal of the R pleural fluid from the patient shown in the previous slide, it is clear there is a tumour mass in the right upper chest (this can be seen in the previous slide also, but is not as obvious with the pleural effusion present). Note the trachea is pushed well over to the left, and below the endotracheal tube (which has been pulled back from its position in the previous slide) it is almost completely obstructed. This resulted in significant gas trapping due to incomplete expiration, with flattening of the diaphragms. On surgical removal, the mass proved to be a neuroblastoma.

R pleural effusion RULRLL

L mainstem bronchus

ETT past L mainstem bronchus (when pulled back it was revealed that there was also a left pleural effusion).

CHEST WALL HAMARTOMA: This tumour has arisen from multiple sites of cartilaginous origin, and there is resultant gross distortion of the first two ribs on the left, both scapulae, at least the first nine ribs on the right, and the lateral processes of C4-6. There was also distortion of the larynx obstructing respiration and making intubation at birth extremely difficult. The right hemithorax contains hamartomatous material also. Generally, the hamartoma grows more slowly than the baby after birth, and may ultimately become amenable to surgical removal in whole or in part.

Another example of chest wall hamartomata. In the lateral projection above right, a mass can be seen protruding forwards from the posterior chest wall, confirmed in the CT scan, showingbilateral masses attached to/ arising from the ribs, the left larger than the right.

PULMONARY HYPOPLASIA shows in this infant with very small lungs, a 'bell-shaped' chest wall, and very large abdomen. He had infantile polycystic kidney disease (note the central abdominal gas shadows, displaced there by the very large kidneys), with severe oligohydramnios and consequent lack of lung growth. This condition is lethal.

Advanced Chronic Lung Disease

This pattern of advanced chronic lung disease shows a great variety of areas of patchy collapse, probably also fibrosis and areas of hyperinflation, particularly at the bases of both lung fields, to the extent that both diaphragms have been flattened by the hyperexpanded lung fields. This particular infant had never received assisted ventilation until this time and this pattern followed the clinical course of that described as Wilson-Mikity syndrome. This infant ultimately died at many months of age of this chronic lung disease.

Rib Fractures

Multiple healed spontaneous rib fractures in this infant with severe and well established chronic lung disease.

Such fractures are not as common now as they were 20 years ago when descriptions of chronic lung disease included rib fractures as a feature of the disease.It now seems more likely that the rib fractures were due to under-nutrition, particularly mineral (Ca & P) deficiencies producing ‘osteopaenia of prematurity’, and sometimes frank rickets, in premature infants. Better attention to mineral nutrition should prevent these fractures.

SOME CARDIAC CONDITIONS Follow this group through sequentially by using the left mouse

number beside the desired slide description. A similar click on the 'Return' button( ) in the bottom right corner of any slide in this

group will bring you back to this menu.

Main Menu5 Vein of Galen Aneurysm

6Tetralogy w absent pulmonary valve

7 Differential cyanosis

1 Patent Ductus Arteriosus

2 Pulmonary Atresia

3 Ventricular Septal Defect

4 Coarctation of AortaA-V Canal

7 Hypoplastic Left Heart

6 Ebstein's Anomaly

99-100

103-104

The cardiac shadow is enlarged, and the pulmonary artery region particularly full in this radiograph of a baby with left-to-right shunt from a PATENT DUCTUS ARTERIOSUS. The lung fields are plethoric, although the right is obscured somewhat by the 'Noah' ECG electrode

After PDA ligation, the heart is smaller with the bulge in the pulmonary artery region having disappeared. The third and fourth ribs on the left are closer to each other than before, as a result of the wound suturing.

Contrast the 'empty' pulmonary artery region in these infants with PULMONARY ATRESIA with that in the previous infant with patent ductus arteriosus. The lung fields in the radiograph at left are also somewhat oligaemic.

Enlarged heart and pulmonary plethora in an infant with Down Syndrome, the cardiac lesion being VENTRICULAR SEPTAL DEFECT and ATRIAL SEPTAL DEFECT. The vessels representing left-to-right shunt can be seen as discrete small round grey shadows in the lung fields, particularly the right.

Cardiomegaly and some pulmonary plethora in an infant with VSD and COARCTATION OF THE AORTA

Significant cardiomegaly and pulmonary plethora in an infant with total A-V Canal

The cardiomegaly and apparent pulmonary plethora in this infant were not associated with any demonstrable structural cardiac lesion on ultrasound examination. The baby had demonstrated intrauterine growth restriction and reverse umbilical artery flow in diastole, indicating the heart was pumping against a high placental resistance. The myocardial performance at birth is sometimes quite poor in such infants.

Massive Cardiomegaly - Great Vein of Galen AneurysmThis infant presented with a loud systolic murmur, very active cardiac impulse and bounding pulses. He began having seizures soon after delivery which were extremely difficult to control.The accompanying CT head scan shows the reason – there was a massive arteriovenous shunt in the brain which was basically one large A-V malformation, leading to a very large blood supply through a low resistant circuit and to dilatation of the great vein of Galen and draining sinuses. These are the radiodense structures in the centre and posterior parts of the CT scan.This baby died, having uncontrollable seizures.

This infant was admitted with a loud to and fro murmur present from birth.Radiographically, the cardiac shadow is of unusual shape and the thymus is virtually absent, giving a rounded shadow across the top of the heart.The lung fields are very under perfused, particularly on the right.The lesion was a Tetralogy of Fallot with an absent pulmonary valve.

Tetrology with absent Pulmonary ValveAnother illustration of the tetralogy with absent pulmonary valve in the same infant, but a little older. The to-and-fro murmur is typical of this condition, and virtually diagnostic in the first day of life.

This infant had an antenatal diagnosis of a major cardiac malformation, probably some variety of Tetralogy of Fallot. Following delivery the infant was extremely poorly perfused and required intubation immediately. On assessment in the Intensive Care Nursery, she was severely acidotic and hypoxic.This radiograph shows a R sided heart and an unusual mass in the L upper thorax. The lung fields give an appearance of possible pneumothoraces, but at later autopsy it was confirmed that there were in fact extremely poorly perfused lungs and no free gas was present.The mass in the L upper chest dilated with each systolic contraction of the ventricles and contracted during diastole. Autopsy confirmed this mass to be a large aneurysmal malformation of the L pulmonary artery with multiple tiny arteries arising from it going to a very small rim of L lung.

The other anatomy was of a Tetralogy of Fallot with absent pulmonary valve. This anomaly is recognised to be associated with aneurysms of the pulmonary artery.

The chest radiograph at left shows mild cardiomegaly and pulmonary changes with a pattern of pulmonary venous congestion. The baby had a hypoplastic left heart, the lesion including mitral atresia. The baby whose chest radiographs are shown below also had a hypoplastic left heart, with worsening cardiomegaly and pulmonary oedema in the few hours time between the two films.

A very large heart and underperfused lung fields at birth in a cyanosed baby are typical of Ebstein's Anomaly, or some other variety of tricuspid valve dysplasia. At this stage, the high pulmonary vascular resistance results in most blood from the right ventricle returning to the right atrium across an incompetent tricuspid valve. With time, as the pulmonary vascular resistance drops, more blood flows into the pulmonary artery, and the baby becomes less cyanosed, or even non-cyanosed.

Note the pink colour of the upper right chest, with cyanosis elsewhere in these infants with DIFFERENTIAL CYANOSIS. This occurs when there is a high pulmonary vascular resistance and the ductus arteriosus is open, resulting in non-oxygenated blood travelling from the pulmonary artery across the ductus arteriosus to the aorta rather than around the lungs. Parts of the body supplied by blood vessels that originate distal to the ductus (about the left subclavian artery) will therefore be cyanosed as the blood supplying them has mixed with pulmonary artery deoxygenated blood. The infant shown above had persistent pulmonary hypertension associated with a diaphragmatic hernia.

Differential cyanosis is not uncommonly seen in the first few minutes of a baby's life, at which stage it is completely physiological. If it persists it may well signify significant pulmonary hypertension.

‘Reverse’ differential cyanosis in a baby with Transposition of the Great Arteries - note the face and upper right chest are severely cyanosed. A slightly irregular line can be seen down the centre of the chest, demarcating the cyanosed right chest and arm from the less cyanosed left chest and arm, and a similar irregular line across the upper abdomen demarcates the less cyanosed lower body from the more cyanosed upper body. The de-oxygenated blood returning to the heart is being recirculated through the aorta which arises from the right ventricle. The oxygenated blood from the lungs is being recirculated through the pulmonary artery arising from the left ventricle. Some of this blood passes across the ductus arteriosus and mixes with the descending aortic blood - hence the partially cyanosed left upper quadrant (left subclavian artery arises near the ductal insertion) and less cyanosed lower body (in this patient the arterial oxygen saturation in the lower body was only 62%. After a balloon atrial septostomy, this increased to 85%).

PNEUMOTHORAX and other AIR LEAKS Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to

one of the slides as listed below by a left-mouse-button click on the number beside the desired slide description. A similar click on the 'Return' button ( ) in the bottom right corner of any

slide in this group will bring you back to this menu.

Main Menu

1 Tension pneumothorax

2 Tension pneumothorax with ICC's

3 ICC insertion

5 Posterior pneumomediastinum

6 Pulmonary Interstitial Emphysema

Anterior pneumomediastinum

7 Pneumopericardium

8 Gas embolism

106-113

114-117

118-119

120-137

138-140

141-149

150-152

Left tension pneumothorax. The left diaphragm is somewhat flattened, and the mediastinum is pushed to the right (even though there is some right-ward rotation in this image). The left and inferior lung edges can be seen with black gas shadows between them and the left chest wall and diaphragm respectively (yellow arrows). The black arrows indicate pleura herniated across to the right anteriorly. The combination of rotation, tracheal push to the right, thymus (right lobe larger than left) and scapula (medial border red arrows) gives the impression of right upper lobe collapse, which is probably not present.

Right pneumothorax

In a baby lying supine, when a pneumothorax occurs the lung falls away from the mediastinum, and pulls away from the chest wall, leaving collections of gas anterior to the lung and between the lung and the mediastinum ('medial pneumothorax' (B)), between the lung and the chest wall (C), and inferior to the lung. The antero-medial lung border appears as a line (A), lateral to which the lung appears as a greyish density because of the A-P thickness through which the x-rays pass, and medial to which lung markings may still be seen through the gas collection (B). The point 'X' represents the highest part of the lung in the supine baby, and the position at which an intercostal catheter should be positioned for best drainage.

The bilateral pneumothoraces in the radiograph taken at 08:00 above of a baby born by elective Caesarean section escaped notice in a small country hospital. Note there is a large amount of free gas anterior to the right lung, and some lateral and inferior to it. There is pleural herniation across to the left above the heart (red arrows at left), some mediastinal shift to the left, and slight bulging of pleura between ribs, especially 4 & 5 on the right. There is some gas below the left lung, and some medial to it at the superior mediastinal level. By 12:00, some resorption of gas on both sides has occurred. Note the right pleural reflection is seen as a 'white' line passing vertically down the centre of the vertebral bodies (yellow arrows).

Left pneumothorax under tension with mediastinal shift to the right, pleural herniation above the heart, and flattened L hemidiaphragm.

Imaginary cross-section of Left pneumothorax. Frequently the area “C” of free gas lateral to the lung is very small, and the area “B” medially contains a large amount of gas which must not be underestimated. A properly placed antero-inferior drain will sit in this space and drain it effectively.

Below is a representation of the tension (L) pneumothorax pictured at left. The area of the heart “A” is less dense than the rest of the heart as it has gas in front of and behind it. The lung surface “S” through which lung markings can be seen is the medial surface which is normally wrapped against the heart and upper mediastinum.

A Right Pneumothorax under some degree of tension

A flattened R diaphragm and a collection of gas underneath the collapsed R lung as well as medial to it and lateral to it are illustrated (the right hemidiaphragm would normally be higher than the left). There is some anterior pleural herniation creating a slightly darker shadowing over the vertebral bodies T3, 4, 5, 6.

Left Pneumothorax

Left pneumothorax with gas lateral to, below, and medial to the L lung. The L diaphragm is flattened. There is also some mediastinal gas lifting the thymus up from the heart, and quite marked mediastinal shift to the right is evident despite the rotation to the right also present. A skin fold passes across the lower lateral portion of the right lung field.

Left tension pneumothorax with inversion of the hemidiaphragm and mediastinal shift to the right. Note that the left lung at maximum collapse still is of considerable volume - this is because of the very high interstitial tissue to alveolar ratio in even the normal newborn lung, more so in HMD.

Positive (L), (upper picture) and negative (R) transillumination of baby with left pneumothorax. The positive lights up the whole of the thoracic cavity.

Right pneumothorax showing medial gas collection only, and effective drainage achieved by a drain inserted from the 5th intercostal space laterally (anterior axillary line is most efficient), with the tip directed antero-infero-medially and positioned near the xiphisternum. Note when deciding how far in to insert the drain, that the distance (in cm) markings on the Argyle catheter (illustrated below) measure distance from the most proximal side-hole, NOT from the catheter tip, which is approx 2cm further on. The 1cm mark at the skin insertion site will see the tip approximately 3cm inside the chest.

Above: Right tension pneumothorax with gas lateral, inferior, medial and anterior to the lung, and pleural herniation to the left, effectively drained by an antero-infero-medially directed ICC.

The tip of the intercostal catheter is actually posterior to the lung. The gas to be drained is anterior to the lung.

Ineffective drainage of left pneumothoraces

In the AP view at left, the ICC appears to be correctly positioned, but the pneumothorax is not drained. The lateral view shows that the tip of the catheter is not anterior to the lung - it probably lies in the interlobar fissure and is not positioned in any of the sections of free gas which are anterior, lateral and inferior to the lung

This infant who is ventilated for hyaline membrane disease has developed R pulmonary interstitial emphysema, and a large R tension pneumothorax. Most of the free gas is collected between the inferior margin of the lung and the right hemidiaphragm, but a rim of gas can also be seen lateral to the lung. There will also be gas in front of the lung, and perhaps a little behind it, accounting for the darker appearance of the R side of the thorax compared with the L. An intercostal catheter is in place, but is not effectively draining the pneumothorax. In such an instance, as shown in the previous slide, the reason is almost always malpositioning of the intercostal catheter. One can be very confident that the tip of this catheter is behind the lung rather than in front of it, so that the lung is resting on the catheter when most of the free gas is in front of the lung.

A lateral film of the previously demonstrated (previous slide) R pneumothorax and interstitial air, illustrating that the tip of this intercostal catheter is indeed posterior. In these circumstances it will drain the pneumothorax very poorly. The tips of all intercostal catheters designed for draining air should be positioned anterior to the lung. Best drainage will also be achieved if the tip is inferomedial. When inserting the drain, after going through the skin into the pleural space, roll the patient away from you and direct the tip of the catheter towards the xiphisternum. Another method of achieving this is to put a 20o – 30o bend on the last 1 cm of the introducer before inserting the catheter and then directing this antero-infero-medially. This position of the tip is the best one for draining subpulmonary gas collections as shown here, and the antero-medial collections that also frequently occur.

If you need to needle a pneumothorax, do it in the 2nd intercostal space mid-clavicular line anteriorly, as shown (left).

That’s away from vital structures on both sides - lateral to the internal mammary artery, superior to heart

ICC INSERTION:

Prep and drape the chest wall on the side of insertion

Choose a position for insertion at the anterior axillary line, 5th or 6th

intercostal spaceIf there is sufficient time, inject 0.5 mls of 1% lignocaine, and allow a minute or two for it to take effect

Incise in the direction of the rib, down to pleura, 0.25-0.5cm. Staying closer to the lower rib will avoid the intercostal vessels which run directly below the upper rib (No.11 blade is held in forceps here)

Placing a 20 deg bend 1cm from the tip of the trochar helps to

direct the catheter tip anteriorly

Holding trochar and catheter with BOTH hands while inserting will stop the catheter from

going in too far. NEVER place palm of hand over the knob on the end of the trochar

Insert the catheter, directing the tip towards the xiphisternum and anteriorly. Sometimes having an assistant roll the baby away from you helps to direct the tip anteriorly. Remove the trochar. The

appearance of humidity in the catheter confirms its tip to be in the pleural space.

Attach the blue end of a Heimlich valve into the catheter. Direct the catheter upwards and under the arm. This will aid in keeping the tip anterior to the lung.

An anterior pneumomediastinum is always characterised by separation of the lower thymic border from the heart, sometimes giving the thymus the appearance of a spinnaker ('sail' or 'spinnaker' sign). There is a right pneumothorax present here also.

Black arrows outline the lower thymic border, clearly seen on the right, not so clear but visible on the left, where the amount of gas in the mediastinum is less.

Double-headed arrows outline gas between the heart and thymus across the top of the heart.

Red arrows indicate the mediastinal pleura which is bowed out laterally as it is distended with gas. It usually meets the right heart border at or just below its half-way point

Double-headed arrows again outline gas between the heart and thymus across the top of the heart.

The single-headed black arrows point to the lateral borders of the thymus. These would appear the same without a pneumomediastinum being present.

As in the previous slide, red arrows indicate the mediastinal pleura which is bowed out laterally as it is distended with gas. It usually meets the heart border at or just below its half-way point

Bilateral pneumomediastinum with the thymus elevated above the heart. Note the intercostal catheter on the left successfully draining a pneumothorax does NOT drain the pneumomediastinum, where the gas is contained within the mediastinal pleura

Bilateral anterior pneumomediastinum, and left pneumothorax, probably with mediastinal shift to the right although the rotation of the patient makes this difficult to assess.

Red line follows the lower border of the thymus, often 'wavy'.

The black oval shapes outline segments of the sternum appearing in this rotated radiograph (see earlier section 'Potentially Confusing Shadows' - these sternal segments can also be seen in some of the radiographs in previous slides - did you see them?).

"B" indicates the gas of a left medial pneumothorax. There is some gas lateral to the lung, particularly low down ('C'), and below the lung also.

The second thoracic vertebra (T2, red arrow) appears to be a'butterfly' vertebra.

Lateral view of anterior pneumomediastinum

The thymus can be seen above the mediastinal gas shadow which lies above and in front of the heart. A lateral view of a pneumothorax may look similar, but the thymic shadow will sit directly on top of the

heart in the upper part of the chest.

Thymus

Gas of pneumomediastinum

Anterior Pneumomediastinum and Left Pneumothorax The thymus is lifted well above the cardiac shadow in the anterior mediastinum.

The L lung field is blacker than the R and a rim of free gas can be seen lateral to the lung and between the lung and the L hemidiaphragm. There is some rotation of this baby to the right.

Anterior Pneumomediastinum and Left Pneumothorax The thymus is lifted well above the cardiac shadow in the anterior mediastinum.

The L lung field is blacker than the R and a rim of free gas can be seen lateral to the lung and between the lung and the L hemidiaphragm. There is some rotation of this baby to the right.

Thymus

Mediastinal free gasMediastinal edge

Anterior Pneumomediastinum and Right Pneumothorax The thymus is again lifted well above the cardiac shadow in the anterior mediastinum. This is sometimes

called the 'spinnaker' or 'sail' sign. The ‘bubbly’ pattern over the left heart indicates the presence of pulmonary interstitial emphysema.

Anterior Pneumomediastinum and Right Pneumothorax The thymus is again lifted well above the cardiac shadow in the anterior mediastinum. This is sometimes

called the 'spinnaker' or 'sail' sign. The ‘bubbly’ pattern over the left heart indicates the presence of pulmonary interstitial emphysema.

Mediastinal free gas

Thymus

Anterior Pneumomediastinum

The gas leak into the anterior mediastinum has lifted the thymus up off the heart, and pushed the lung away from the heart on both sides. This pattern is different from that of a medial pneumothorax where the thymus is not lifted off the heart.

Mediastinal pleura

Pneumomediastinum lifting only the Left lobe of the thymus from the heart.

Mediastinal pleura

ThymusScapula

Lung edge

Right pneumothorax and pneumomediastinum lifting the right lobe of the thymus from the heart. Note after

the pneumothorax is drained (below) the pneumomediastinum remains, as that gas is in a different space. Press the right arrow to see the

features outlined, left arrow to remove the outlines.

Pneumomediastinum and R Pneumothorax

Both lobes of the thymus are lifted separately from the heart. There is free gas medial to and lateral to the R lung (and there will be gas anterior to it also).

The two radiographs shown here were taken within a few minutes of each other. What do you see here? - see next slide after you have made up your mind!

The two radiographs shown here were taken within a few minutes of each other. Both show a L pneumothorax and a pneumomediastinum which were not recognised by the radiologist reporting the films. The pneumothorax was not diagnosed until 4 hours later when the infant was much sicker. The L lungfiled is darker than the R, and a clear rim of free gas is seen over the L diaphragm, larger in ‘A’. There is much rotation, but also probably mediastinal shift to the right. A clear rim of free gas is seen down the L heart border in ‘B’.

Same infant as in previous slide - Chest radiograph at 12 md shows the L pneumothorax more clearly. The infant was much sicker by this time and required intubation and ventilation as well as drainage of the pneumothorax.

Right pneumothorax with free gas medial to and below lung. Note there is gas in the anterior mediastinum on the left, indicated by the separation of the thymus from the upper cardiac border

The pneumothorax is effectively drained by an intercostal catheter. Black arrows indicate the lower edge of the thymus.

Further example of anterior pneumomediastinum Tension right pneumothorax - note the flattened right hemi-diaphragm, pleural herniation across the midline above the heart, mediastinal shift to the left, and bulging of pleura between the upper ribs on the right (red arrows).

A Ventilated Infant in Recovery Phase of HMD

In the R hemithorax a vertical shadow about 1 cm in from the R chest margin passes from the region of the horizontal fissure down and across the R diaphragm. This is an artifactual shadow, probably caused by a skin fold. It was interpreted as being a lung edge and indicative of a pneumothorax.

After a number of attempts to aspirate the apparent pneumothorax illustrated in the previous slide, the baby developed a dense white shadowing in the R hemithorax and extensive shift of the mediastinum to the L. This is a very large R haemothorax, due to a needle used for aspirating the pleural cavity hitting the internal mammary artery on this side. It ultimately led to this baby’s demise. The internal mammary artery runs just lateral to the sternum and this area must be avoided when aspirating the pleural cavity. The needle should not be used more medially than the midclavicular line.

Note: There are some artifactual lines in the L hemithorax similar to those present in the R hemithorax in the previous illustration.

The gas shadow in the region of T7-9 vertebral bodies (outlined in copy at right) is the typical appearance of a small posterior pneumomediastinum. From here gas may sometimes leak into the peritoneal cavity. Gas in the posterior mediastinum is usually quite benign and reabsorbs of its own accord without adverse effects on the patient. See next slide.

Same patient as in previous slide who was clinically deteriorating. The amount of gas present has increased dramatically (this is quite unusual). The lateral radiograph on the right confirms this gas is in the posterior mediastinum. In this patient echocardiography showed that the heart was being compressed from behind with each inspiratory cycle of the ventilator, impeding pulmonary venous return. This is one of the very rare (only 2) occasions when I have had to drain a posterior pneumomediastinum - this was done by inserting a catheter into the gas space shown above , approaching from the posterior aspect of the left chest (a pneumothorax occurred during this procedure, necessitating insertion of more conventionally placed intercostal catheters also).

Posterior pneumomediastinum in a baby ventilated for meconium aspiration, who later developed a pneumoperitoneum (above right). Gas can be seen both above and below the liver in this supine film. There were no signs of gut pathology, and the pneumoperitoneum resolved spontaneously. There was subcutaneous 'surgical emphysema' in the neck at the time of the pneumoperitoneum.

(Have you noticed the 13 pairs of ribs, 'butterfly' C7, and 6 lumbar vertebrae? - same patient as previously shown with meconium aspiration).

PULMONARY INTERSTITIAL EMPHYSEMA is gas that has leaked out of airways and is trapped in the interstitial tissues of the lung. It is not available for gas exchange. It may accumulate during inspiration, but does not get less during expiration. The lung or lung segment with PIE will often appear hyperexpanded, and will have increased airways resistance. In the radiograph illustrated here, there is PIE in all segments of both lungs. This appears as multiple black 'bubbles'. Hyperexpansion of the affected areas is evident. The diaphragm is flattened on both sides. The heart is compressed & systemic venous return is impeded.It is believed that all air leaks in the newborn occur centrally near the hilum, from where the extrabronchial gas gains entry to the pleural space, the interstitial space, the pericardium, or theanterior or posterior mediastinum.

Pulmonary Interstitial Emphysema (PIE)This infant was ventilated for hyaline membrane disease. There is some tension with a flattened R hemidiaphragm and some mediastinal shift to the left. Note the coarse, irregularly sized and sometimes linear 'bubbles' throughout the right lung, and some in the left upper lobe. These are sometimes called 'Type II (two) bubbles'.

Bilateral Pulmonary Interstitial Emphysema (PIE) in a baby ventilated for HMD, also having a right pneumothorax which is effectively drained by an intercostal catheter.

Pulmonary Interstitial Emphysema (PIE) This occurred in a spontaneously breathing 1630grm infant with moderate HMD. There is significant hyperexpansion of the R hemithorax. It is very uncommon to see PIE in infants of >36 weeks gestational age - their lung structure appears to be more robust.

PIE in spontaneously breathing infants generally occurs only in 'middle-sized' infants (1250-1800g) whose lungs have the immature structure which is prone to PIE, and who have sufficient chest wall and muscular strength to develop the pressure necessary to cause an air leak.

Same baby as previous slide - spontaneous resolution of PIE occurred (as it often does) at 12 days of age. The R hemithorax is now of reduced volume, and the lung field generally hazy.

Further example of severe bilateral pulmonary interstitial emphysema with flattening of the diaphragms and mediastinal compression.

Post-mortem radiograph of lungs with PIE of the right lung, left upper lobe and lingula show that the gas persists after death, while the unaffected left lower lobe is quite dense and free of any gas. The photograph of the same lungs at right shows the bubbles of PIE on the inferior surface of the left lung (but not the lower lobe).

Right unilateral PIE with dramatic hyperexpansion of the right lung and mediastinal shift to the left. Note the right hemidiaphragm is inverted, sometimes called ‘tension PIE’.

Right PIE with marked hyperexpansion of all segments of the right lung and mediastinal shift to the left. The right upper lobe PIE is herniating across the upper mediastinum into the left hemithorax.

Further and even more dramatic hyperexpansion of the right lung with continued ventilation.

If severe PIE does not claim the baby's life, it will usually suddenly disappear at about 12-14 days of age - where does it go? It must drain into pulmonary veins or lymphatics. This is the same patient as shown in the previous slide, after sudden overnight resolution of PIE. Note that the right lung is far from normal in appearance, with PIE being almost always a precursor to significant chronic lung disease.

The twin of the previously shown baby at left also had severe PIE, with some of the cysts of interstitial air on the left becoming very large.

PNEUMOPERICARDIUM is characterised by the presence of gas completely surrounding the heart, with the cardiac shadow looking less dense than usual. This patient also has significant bilateral interstitial air present.

PneumopericardiumThe gas fully surrounds the heart. There is extensive interstitial emphysema in both lungs also. The endotracheal tube is slightly too long. There is a ‘nasogastric’ tube in place which stops short of the stomach, at T7.

Pneumopericardium occurring in a patient who previously had a pneumatocele from Staphylococcal pneumonia. He died after this complication.

Gas embolism as a complication of ventilation for severe hyaline membrane disease. This is of similar aetiology to other forms of air leak, except that the gas escapes from a bronchus into a pulmonary vein. Note the gas in many parts of the arterial tree - inside the heart, aorta and femoral arteries. The gas in the hepatic vessels here appears to be venous with left and right hepatic veins joining to drain in to the IVC. This would reflect a very large amount of gas to get through the capillary beds. Death is usually swift with this complication. Heart action rapidly becomes inefficient when attempting to pump compressible gas. The gas may also appear in cerebral venous sinuses (below).

GASTROINTESTINAL DISORDERS Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to

Main Menu

4 NEC with perforation

5 NEC with portal vein gas

1 Pneumoperitoneum

2 'Football Sign' description

3 Necrotising Enterocolitis

6 Meconium peritonitis

10 Ovarian Cyst

11 Meconium Ileus

7 Small Bowel Atresia

8 Duodenal Atresia

9 Hirschprung's Disease

12 Malrotation

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186-189

190-191

193-197

198-199

Plain x-ray of the same abdomen illustrates the presence of free gas in the peritoneal cavity as a grey outline around the abdominal edge, with the falciform ligament visible centrally (arrowed). This gas shadow is

sometimes called the 'football' sign (see next slide).

Falciform ligament

Free gas outline

‘Double contrast’

shadowing of bowel

wall - Frimann-

Dahl Sign / Rigler’s

Transillumination of abdomen illustrating the bright illumination of free gas in the peritoneal cavity. Gas

inside bowel loops also transilluminates, but the walls of the bowel loops are visible as dark strands across

the abdomen.

Clinical hint: Note that clinically the abdomen with perforated bowel and hence

free gas is almost always ‘smooth’ in appearance. When bowel loops are visible through the abdominal wall, often called a ‘ropey’ abdomen, free gas is

not present.

Radiology 74:65-67 (1960) (Excerpts from)Original Description of the “AIR DOME” or “FOOTBALL” sign

WORK IN PROGRESS: RADIOLOGIC DIAGNOSISThe final sessions of the 45th Annual Meeting of the Radiological Society of North America were given over to brief accounts of new projects in diagnosis and therapy still in the preliminary stages. Following the plan adopted several years ago for the reporting of current work in the field of radiologic physics, these papers are being presented under the heading Work In Progress.

Perforated Viscus in Infants: A New Roentgen Sign1

ROSCOE E. MILLER, M.D.A new roentgen sign has been found on supine films by which the characteristic pneumoperitoneum may be recognised, namely a huge oval shadow outlining the periphery of the peritoneal cavity. In the presence of a significant amount of fluid, this shadow appears as a large bubble of gas centrally located in the abdomen, divided in its cephalad portion, along its central longitudinal axis, by a narrow streak which represents the falciform ligament. Occasionally, the caudal half is divided by a similar streak, representing the urachus (the plica umbilicalis media). The oval shadow produced by the air-filled dome of the distended abdomen has been likened in appearance to an American football. While this sign has been seen most frequently in infants, we have encountered it in a 4 year old boy with a perforated duodenal ulcer. Sometimes the outline is irregular, but the general oval shape is maintained.A review of the literature reveals reports of over 59 such infantile catastrophes in the stomach alone. One article (8) states: ‘It should be recorded that in the horizontal posture, the true nature of the abdominal distension could not be ascertained’. Caffey in his book Pediatric Xray Diagnosis also stresses that ‘films and fluorographic observations made in the recumbent position revealed nothing but abdominal distension’. In the light of our present observations, these statements would appear to be too conservative. In the 9 instances in which supine roentgenograms have been published, the sign is recognisable even in poor reproductions.There are only a few even remotely similar pictures, which have not yet occurred in our material. An air-filled megacolon could possibly mimic this sign. Also theoretically possible is the extreme distension sometimes seen in volvulus of the sigmoid or a rectus sheath gas abscess. There should be no difficulty in correct interpretation when one considers the presence of haustral markings, fecal material and the overall pattern of the bowel loops. The characteristic oval line of the ‘air dome’ divided by the streak of the falciform ligament is pathognomonic.

A true ‘football sign’ – there is just the right amount of gas and fluid to make the shape of an American football, as described, (I think it’s mostly more like a Rugby Union football, but Roscoe Miller wouldn’t have seen one of those) inside the abdominal cavity. The arrow points to the falciform ligament.

Further examples of intraperitoneal free gas. Falciform ligament

There is a small oval of free gas in the centre of the upper abdomen, which rises above the right lobe of the liver in the lateral decubitus view at above right.

The free gas overlies the liver.

There is 'double-shadowing' of bowel walls in the abdomen (Frimann-Dahl sign / Rigler’s sign)

The free gas is below the liver

'Double-shadowing' of bowel walls indicative of free gas in abdominal cavity. This is also known as the ‘Frimann-Dahl’ sign or Rigler’s sign.

'Double-shadowing' of bowel walls indicative of free gas in abdominal cavity.Free gas

(did you see it?)

This unusually shaped shadow should raise your suspicion of free gas - there is no anatomical structure that will contain a gas shadow shaped like this.

Can you see any shadows suggesting free gas in these radiographs?

(See next slide)

Gas and fluid level in

stomach

There are 2 shadows in the supine film at left which do not conform to any anatomical structure, and represent free gas. They also have sharp triangular corners . In the lateral decubitus view above, the gas outlined has risen upwards, but is difficult to see. If this view had been taken with the right side up, it may well have been clearer that this is free gas, as it would have risen above the right lobe of the liver, and separated it from the abdominal wall.

Press ‘Page up’ or left arrow to remove outlines and text, ‘Page down’ or right arrow to restore them.

Free gas

Gas in stomach

The following day there is more free gas present, seen in the supine radiograph at left to be contained to the left of the falciform ligament. When the infant is placed in the lateral decubitus position (above), the gas remains trapped to the left of (now below) the falciform ligament, with a fluid level below it.

Falciform ligament

Does this represent a G-I perforation?

No. This is not a G-I perforation. The falciform ligament is not evident at left, there is no Frimann-Dahl sign, and the indentation in the centre inferiorly indicates that the shadows there represent gas in two overlapping loops of bowel. In the lateral decubitus view above, if there were free gas present, one would expect to see a straight line of the inferior edge of gas, and the left lobe of the liver would be separated from the diaphragm and lateral abdominal wall, rather than pushed up against them.

NECROTISING ENTEROCOLITIS: Characteristic of this condition is pneumatosis intestinalis - gas in the submucous layer produced by intestinal bacteria. When a loop of bowel is viewed end-on, one sees intraluminal gas or fluid surrounded by oedematous mucosa, then the submucous gas, then the serosa. In the right iliac fossa of the radiograph at right note two circles of gas produced by two loops of partly fluid filled bowel viewed end-on with submucous gas present. The horizontal lines in these bowel loops in erect view indicate the fluid-gas interface in the bowel lumen with ileus present.

NEC: Similar to previous slide. Multiple fluid levels present.

There are 3 patterns of bowel gas to look for in NEC (1) the circle of submucous gas in a cross-section of bowel viewed end on (2) a 'train-line' appearance of submucous gas in bowel viewed in longitudinal section and (3) a 'whorl' pattern seen when looking through a bowel wall with pneumatosis in it. Other signs to look out for in NEC are (1) portal venous gas in the liver (2) generalised or local distension from ileus and (3) separation of bowel loops by extra intraperitoneal fluid.

Look for these patterns in the slides which follow.

NECROTISING ENTEROCOLITIS:

Submucous gas

Oedematous mucosa

Intraluminal gas

When viewed through longitudinally-oriented bowel, pneumatosis appears as a track along the outer edges of the bowel, with a swirling 'whorl' pattern across the bowel as it is viewed through the bowel wall. Note at the splenic flexure the circle of submucous gas in an end-on view of the bowel.

Note also the circle from the incubator hole in the middle of the upper abdomen right at the top of this slide.

NEC with perforation. The falciform ligament is clearly outlined.

Intraluminal gas Mucosa Submucous gas

The pneumatosis present in the right iliac fossa of this infant with necrotising enterocolitis is enlarged at right (press ‘Page Down’ or Right Arrow to see)

Pneumoperitoneum with NECThe main sign of free gas in the abdominal cavity visible in this film is the double contrasting across the bowel wall seen when there is gas both inside the bowel lumen and outside the bowel (Frimann-Dahl Sign).The accompanying diagram also illustrates the margins of free gas across the liver which can be seen on close inspection and are also indicative of pneumoperitoneum.

(Falciform ligament)

Lateral decubitus film taken with the R side of the patient up shows more clearly the free intraperitoneal gas of the baby of the previous slide.Some double contrasting of bowel gas shadows is evident here.When looking for free intraperitoneal gas, if a lateral decubitus film is to be taken, the R side up view is the better one to choose as one can then clearly delineate the free gas above the liver shadow.

NEC with perforation: If a radiograph of a baby with free intraperitoneal gas is taken in an erect view (right), the gas appears between the liver and the diaphragm across the upper abdomen.

NEC: Submocosal gas is sometimes absorbed into the portal venous system and travels to the liver. Tracks of portal venous gas within the liver can be seen in the radiograph at left. There is also free gas in the peritoneal cavity in this film - its outer edge is outlined by the white line above.

Intestinal Dilatation with NEC

Marked intestinal dilatation in an infant with Necrotising Enterocolitis. The dilatation comes from ileus which occurs in the presence of the enteric inflammation. There are some areas of pneumatosis present here.

The main feature of significance to note in this radiograph is the presence of linear gas shadows within the liver as also seen in the previous slide – these are representative of gas in the portal venous system. The gas tracks from the intestinal wall up the portal vein and through the liver. It can sometimes be seen to be doing this on real time ultrasound examination.

Pneumatosis across transverse colon. At the hepatic flexure, one can see a circle of intramural gas where the bowel is viewed in cross-section. At various parts across

the transverse colon, one sees the 'train line' effect of intramural gas running linearly outside oedematous mucosa.

Further example of pneumatosis across the transverse colon. In general terms, large bowel NEC is a much more benign illness than small bowel NEC.

Necrotising enterocolitis - pneumatosis intestinalis.

Assess the features of NEC in these two radiographs, then move to the next slide.

Portal venous gas

Pneumatosis

Extra fluid between bowel loops

MECONIUM PERITONITIS occurs following a gastrointestinal perforation occurring in utero, with resultant scattered peritoneal calcification as shown above. After birth, if the perforation remains, peritoneal free gas may occur, again illustrated in the erect AP radiograph at left, and in the lateral at right. The commonest underlying pathology would be cystic fibrosis with meconium ileus.

In this supine radiograph, some hugely dilated loops of bowel are visible.

In erect view, fluid levels can be seen in the stomach, proximal duodenum, and one other more distal bowel loop. This was a small bowel atresia, but small bowel volvulus is not excluded on this appearance.

A further demonstration of small bowel atresia in supine and erect views. This baby had no further small bowel than that demonstrated here, and the condition was lethal. The most likely cause of such an atresia is an in utero volvulus with infarction and subsequent reabsorption of the midgut.

The baby showed visible distended bowel loops across the abdomen

This 'J' shaped shadow is representative of gas in a distended stomach and duodenum in supine view, typical of duodenal atresia.

Placed in the erect position, the fluid and gas present in the stomach and the dilated proximal duodenal segment form the 'double bubble' shown above.

In clinical history, a mother carrying a fetus with this lesion (or high small bowel atresia) will sometimes have polyhydramnios from reduced fetal swallowing of liquor, and / or fetal vomiting. In labour, bile stained liquor from fetal vomiting is often misinterpreted as meconium staining of the liquor. After birth, vomiting which may or may not be bile stained may occur. If a naso-gastric tube is inserted, a large volume of fluid may be aspirated from the stomach. In a baby with normal bowel, it would be uncommon to get > 10 mls of fluid from the stomach after birth. In small bowel atresias, it is not uncommon to get >100 mls.

When gas is present elsewhere in the abdomen, the lesion is likely to be duodenal stenosis, often with an annular pancreas present, allowing a small amount of gas to pass. The contrast study at right shows a distended stomach and duodenal cap, with a small trickle of contrast passing through the stenosis.

The infant pictured above had a grossly distended abdomen with an unusually shaped mass. His abdominal radiograph at right showed complete absence of any gas. The abnormalities present were oesophageal atresia with no tracheo-oesophageal fistula, and duodenal atresia. This resulted in all gastric secretions throughout fetal life collecting in and distending the stomach and proximal duodenum (this is the only patient in whom I have seen this combination of abnormalities).

The infant pictured here presented with persistent vomiting. The radiograph at right is after introduction of some radiopaque contrast material into the stomach, which is shown to be grossly enlarged. A duodenal web was found at laparotomy.

This radiograph taken on the second day of life of a baby who had failed to pass meconium shows marked dilatation of the upper bowel, with multiple fluid levels in erect view. The appearances are not specific to any one diagnosis, but differential diagnosis must include Hirschprung's Disease, Meconium Ileus, large bowel or low small bowel atresia (although the presence of a small amount of gas in the rectum would make atresia unlikely, unless it had been introduced by rectal examination or instrumentation).

This radiograph, of a lower bowel contrast study of the same baby as in the previous slide, is also not specific for any particular diagnosis. It was however taken as a late film 24 hours after the contrast study, making Hirschprung's Disease the most likely diagnosis, as normal bowel motility would usually evacuate the contrast material quickly after such a study.

The baby shown in this radiograph had marked abdominal distension, but no gastrointestinal symptoms. The bowel can be shown to be pushed to the right by a mass apparently arising from the left lower abdomen. This baby presented before ultrasound examination was readily available, and at laparotomy a large left ovarian cyst was removed. After ultrasound diagnosis, needle aspiration of such a cyst is sometimes now regarded as acceptable treatment.

Gaseous distension of gut, with gas present in the rectum, are noted in this radiograph of a baby failing to pass meconium by 48 hours of age. The 'empty right iliac fossa' suggests the caecum is either empty or filled with non-gaseous material. The microcolon illustrated in the contrast study at right indicates that the colon has not had any solid contents in it for a long time. This baby had cystic fibrosis with meconium ileus. Note the small pellets of solid meconium in the ascending colon only.

Another example of an empty right iliac fossa, this time with no gas in the rectum. The baby had an atresia of the transverse colon, with solid meconium impacted in the caecum and ascending colon.

What can you make of this appearance? There is a large central gas shadow in the supine view at left, which appears to move to the left upper quadrant and contain a fluid level in the erect view at right. Signs were sufficient to justify laparotomy (see next slide).

At laparotomy, a large loop of twisted and semi-viable small bowel was found as a small bowel volvulus. This will not usually happen to normal small bowel with normal intraluminal contents - the underlying condition here was cystic fibrosis with the bowel containing very viscid meconium.

Sometimes such a volved segment of bowel may perforate in utero, and if the perforation has not fully walled itself off prior to delivery, a pneumoperitoneum will then occur after the baby swallows air.

This plain abdominal radiograph taken of a baby with persistent vomiting shows a dilated stomach and proximal duodenum.

When an upper GI contrast study is done, note again the dilated stomach and duodenum with sudden narrowing at the distal 3rd part of the duodenum, and the short 'tail' of a reverse 'C' as the small bowel flicks over to the right, instead of up to the left as would be normal - this is a MALROTATION of the gut, probably with 'Ladd's bands' across the distal duodenum..

Another view of an upper GI contrast study in a baby with malrotation, showing the proximal small bowel to drop away inferiorly from the distal duodenum. Normally the small bowel goes up to the left upper quadrant from the duodenum, and fills the abdominal cavity from there to the right iliac fossa.

INTRAVENTRICULAR HAEMORRHAGE Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to

Main Menu

4 Grade 2 IVH

5 Grade 3/4 IVH

1 Normal Ultrasound scan

2 Third Ventricle

3 Grade 1 IVH

6 Periventricular Echodensity

7 Periventricular Leucomalacia

8 Evolution of IVH / PVL

9 Lenticulostriate vasculopathy

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203-204

206-207

208-214

215-216

217-222

223-239

10 Paraventricular cysts 241

Normal cranial ultrasounds - identify the structures shown here, then click to next slide

Normal cranial ultrasounds - identify the structures shown here

Choroid plexus

Caudo-thalamic groove

Caudate nucleus

Thalamus

Interhemispheric Fissure

Supra-pineal recess

Pineal recess

Aqueduct of Sylvius

Interthalamic Adhesion

Optic recess

Infundibular recess

The Third Ventricle

(The 3rd ventricle and its recesses and the interthalamic adhesion are seen as clearly as shown here only when the ventricle is dilated)Optic

4th ventricle

Foramen of Monro (Interventricular Foramen - between the lateral

and 3rd ventricles)

IVH grade 1

Grade 1 ‘IVH’ is a sub-ependymal bleed only. It is usually distinguishable from the choroid plexus by being anterior to the caudothalamic groove as

shown at right

IVH grade 2

Grade 2 IVH is intraventricular blood, without ventricular enlargement. Ependymal enhancement as seen here suggests IVH as it is indicative of inflammation caused by intraventricular blood (or infection). There is probably some clot hanging off the back of the choroid plexus in the sagittal view at right.

IVH grade 2

Grade 2 IVH is intraventricular blood, without ventricular enlargement. Ependymal enhancement as seen here suggests IVH as it is indicative of inflammation caused by intraventricular blood (or infection). There is probably some clot hanging off the back of the choroid plexus in the sagittal view at right.

IVH grade 2

As in previous slide, ependymal enhancement is indicative of inflammation caused by intraventricular blood (or infection). There is more obviously some clot hanging off the back of the choroid plexus in the sagittal view at right.

IVH grade 4

Smooth outer edge

'Apex' of triangle midline (next slide)

Evolves to porencephaly

IVH grade 4

Smooth outer edge

'Apex' of triangle midline

Evolves to porencephaly

IVH grade 3 (& 4)

Day 5 Day 5

Left sided grade 4 IVH (intracerebral bleeding - venous infarction) at 5 days of age in an infant of 26 weeks gestational age. There is a grade 3 IVH present on the same side also, with dilatation of both ventricles. This infant had had an only mildly abnormal

scan on the first day of life (below).

Further maturation of the intraventricular and intracerebral haemorrhage at 16 days of age. There is now some early cavitation in the haemorrhage, as well as dilatation of

the ventricles with early post-haemorrhagic hydrocephalus.

Day 16 Day 16

Day 30 Day 30

Day 30

At 30 days there is progressive cavitation and hydrocephalus. Ultimately a porencephalic cyst forms, and ventriculo-peritoneal shunting was required. (Note

‘porencephalic’ cyst by definition communicates with the ventricle).

PVE - periventricular echodensity

Fluffy outer edge

'Apex' of triangle at lateral edge of ventricle (next slide)

Evolves to multiple non-communicating cysts of cystic PVL

PVE - periventricular echodensity

Fluffy outer edge

'Apex' of triangle at lateral edge of ventricle

Evolves to multiple non-communicating cysts of cystic PVL

Cystic periventricular leucomalacia arises as a result of periventricular ischaemia, occurring around the time of a significant adverse event such as hypotension or infection. Initial changes are minimal, or there may be a degree of periventricular echodensity (‘PVE’) representing localised oedema. The PVE resolves over 1-2 weeks, leaving either normal appearing brain or damaged brain in the form of small cysts which do not communicate with the ventricles, as shown above (cystic PVL). These in turn also resolve, usually leaving some ventricular dilatation in their wake. It is wise to do a late (4-6 week) scan on babies born at <32 weeks GA, or others considered at risk, to look for cystic PVL.

PVL - periventricular leucomalacia

Day 3 (above) - this scan is not normal, with very small ventricles, and ill-defined periventricular structures.

By 4 weeks (right) severe cystic PVL is evident. This has a very high correlation with later appearance of clinical cerebral palsy, often severe.

3 days

Development of cystic PVL: In this day 4 scan of this baby of 29 weeks gestational age and 1240g birth weight, bilateral periventricular echodensities are present, indicating a recent insult (within the last few days, but not the last few hours), probably with some localised oedema in the compromised periventricular white matter. There are bilateral subependymal haemorrhages present also, with some intraventricular blood as evidenced by the ependymal enhancement. The risk factor in this pregnancy was placenta praevia with multiple antepartum haemorrhages. The baby post-natally was not unwell.

1 week later, the echodensities have largely resolved. There is mild ventricular dilatation from blockage of the CSF circulating system by the intraventricular blood, and more marked ependymal enhancement in the lateral ventricles.

By 19 days, the previous echodense areas are beginning to show signs of cyst formation as damaged tissue is removed by the repair process. Here the cystic periventricular leucomalacia is worse on the right than the left.This is the typical time frame for development of cystic PVL from the time of an ischaemic brain injury (2-3 weeks).

A classification of PVE / PVL

• Grade I - periventricular echodensity lasting >7d

50% gone 10days, 10% evolve to cysts

• Grade II - PVE evolving into small fronto-parietal cysts

• Grade III - PVE evolving into cysts in parieto-occipital white matter

• Grade IV - PVE in deep white matter evolving into multiple subcortical cysts

By 4 weeks of age, the cystic PVL is well developed, still worse on the right side. With further time, the cysts of leucomalacia also disappear, with the whole area becoming ‘scarred’, and ventricular dilatation from cerebral volume loss becomes apparent - the leucomalacia (no longer cystic) is then not detectable by ultrasound examination, but remains so by MRI. The important late (4-6 week) cranial ultrasound examination in ‘at-risk’ babies will pick the cystic stage of PVL.

At 9 months of age, this infant exhibited significant motor developmental delay and signs of spastic quadriplegic cerebral palsy.

EVOLUTION of IVHGrade 3/4? IVH + PVL

Day 2 scan in a 27 week infant revealing bilateral grade 3 IVH with a right PVE.

Day 2 Day 2

By day 7 blood clot is retracting away from the wall of the left lateral ventricle, and the PVE remains dense.

Day 7 Day 7

Day 21 Day 21

Day 21 - there is significant ventricular dilatation with some early cyst formation in the right PVE. The clot in the right ventricle (below) is adherent to the ventricular wall.

Day 21

Day 35 Day 35

Day35 - the ventricular dilatation has resolved spontaneously. There is probably a small porencephalic area from the right ventricle (declaring the IVH to have been grade 4), as well as cystic periventricular leucomalacia in the previous PVE.

Bilateral IVH grade 2 + L PVE (fronto-parietal) on day 3

Day 3 Day 8

Sagittal view of the ‘fluffy’ densities of L fronto-parietal PVE on day 3 of life

Ventricular dilatation occurs by day 8. Note the dilated 3rd ventricle and the clear view of the interthalamic adhesion in the sagittal view.

Further ventricular enlargement (note dilated temporal horns of the lateral ventricle) has occurred by day 15, then some spontaneous resolution of the hydrocephalus is evident by day 19.

Day 15 Day 19

Day 15

Some early cavitation appears in the area of PVE by day 19. This usually takes 2-3 weeks to develop.

Day 15 Day 19

Day 26

Cystic PVL

Day 26 - there is resolution of PHH, and further cystic periventricular leucomalacia is now obvious in the area of the previous periventricular echodensity.

Day 3 Day 3

Day 10 Day 10

Watch the progress of this IVH from day 3 R gr 3 + PVE to post-haemorrhagic hydrocephalus + PVL Day 28

Day 28

Twin - twin transfusion is a very high risk for PVL, particularly with the death of one twin.

Severe bilateral cystic PVL This baby was the donor twin in a twin to twin transfusion situation, delivered after developing hydrops following the in utero death of the recipient twin. 3 day scan shows bilateral generalised periventricular echogenicity developing into very severe cystic PVL by 20 days.

Severe bilateral cystic PVL Found in this baby at 7 weeks of age. He had been born at 32 weeks GA, weighing 1690g, after 3 weeks rupture of membranes, with clinical amnionitis and flat CTG preceding delivery. He was colonised with Staph aureus and E coli at birth. The scans show normal ventricles, but with severe bilateral cystic PVL (see next slide also). He was not unwell after delivery. He missed his routine 4 weeks ultrasound by being discharged home well at 27 days of age.

Normal ventricle

This view is anterior to the ventricles.The ‘holes’ are PVL

This view is superior to the ventricles.

Sagittal views of same patient as previous slide, showing severe cystic PVL, mostly anterior and lateral to both ventricles, with some in the parieto-occipital region above the left lateral ventricle.This clearly has arisen resulting from events preceding delivery. The 3-day scan showed mild increased echogenicity in the periventricular white matter bilaterally, the 10-day scan was ‘normal’.The best explanation we can offer at this stage of our knowledge is that periventricular ischaemia results from the influences of vasoactive inflammatory mediators (prostaglandins, leukotrienes, interleucins) which circulate in the presence of amnionitis, and this ischaemia progresses to cystic PVL.

Right Left

Echogenicity of the lenticulostriate arteries (sometimes called the ‘candelabra sign’) is an uncommon finding on cranial ultrasound examination. It is not known to be independently associated with adverse neurologic outcome. It has been noted in some cases of congenital infection (CMV, toxoplasmosis, rubella, syphilis), acquired bacterial infection, asphyxia and occasionally in aneuploidy. Histopathologic examination in a few cases suggests a post-vasculitic vasculopathy with hypercellular arterial walls and iron, but not calcium, deposition in the vessel walls.

See Swaminathan et al, Australian Society for Ultrasound in Medicine Bulletin Vol 1/ #4, 1998: 38-41.

Paraventricular cysts

Variously called ‘paraventricular cysts’ or ‘intraventricular adhesions’, the cystic lesions shown here are seen in approximately 0.7% of first cranial ultrasound scans in VLBW babies, and persist for at least a few weeks. They may enlarge, and later disappear by 2-4 months. Routine autopsy may fail to find them - do they collapse? Autopsy on one baby specifically looking for these cysts, described in the study below, found the cyst in the periventricular white matter, not distorting the surrounding tissues. It was lined by nodules of neuroblasts and other cells suggesting ependymal origin. There was no evidence of recent or old haemorrhage - there have been suggestions these ‘adhesions’ are the remnants of in utero IVH. In the absence of other pathology, neurodevelopmental outcome appears to be normal.

See Pal et al, ‘Frontal horn thin walled cysts in preterm neonates are benign’ - Arch Dis Child Fetal Neonatal Ed 2001: 85; F187-F193

Cavum septum pellucidum

Ventricles

COMPLICATIONS OF VENTILATION Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to

Main Menu

1 The Endotracheal Tube

2 The Airway

3 Pneumothorax

4 Pneumperitoneum

5 Other air leaks in main presentation ‘Pneumothorax and other air leaks’

243-253

254-260

261-262

105-154

Look here at the ‘blue line’ - it is more radiopaque than the remainder of the ETT, and runs down the right side of the tube as you look at this radiograph. Note also it is ‘twisted’ in the mouth so that it exits the mouth at the lower, rather than the upper lip.

The endotracheal tube in both of these radiographs has been advanced too far, and its tip is in the right main-stem bronchus, with collapse of left lung and right upper lobe in the patient shown above.

More rarely, an ETT advanced too far will find its way into the left main-stem bronchus. This has produced dramatic hyperexpansion of the left lung (above left), looking like a pneumothorax, which it was not. Above right, the picture is one of collapse of the right lung and left upper lobe, with only the left lower lobe being ventilated.

Complete right upper lobe collapse may occur after removal of an endotracheal tube which has previously been positioned too low. Note (above left) the horizontal fissure is pulled upwards by the lobar collapse, and the trachea is pulled to the right. The asymmetry of the anterior rib ends indicates that the baby was rotated to the left when this radiograph was taken. In the radiograph above right, there is mucous plugging of the right main-stem bronchus with collapse of the right lung.

The upper lobe bronchus takes off from the right main stem bronchus just below the carina, and travels postero-superiorly, before further branching. Thus positioning for draining this bronchus is 1/4 off prone, right side up, with slight upwards head tilt.

Neonatal ETT Placement(orotracheal tubes)

1 2 3 4

ETT LIP toTIPDISTANCE

Weight (Kg)

The 1 - 2 - 3 / 7 - 8 - 9 RULE

Neonatal ETT Sizes

Endotracheal Tube Sizes = GA / 10

25 weeks - 2.5 mm

30 weeks - 3.0 mm

35 weeks - 3.5 mm

40 weeks - 4.0 mm

This ETT is in the trachea, but only just through the larynx, so gas is being blown into the oesophagus as well as the trachea. The oesophagus and stomach are both extensively dilated. A ’cure’ was effected just by advancing the ETT.

Oesophageal intubation: note the ETT here passes into the oesophagus behind the trachea (to the right in this radiograph). The epiglottis (‘page down’ to outline, ‘page up’ to remove outline) can be clearly seen outlined by gas in the pharynx, and the trachea below the larynx is gas-filled.

While the head is turned to the right, the ETT passes to the left of the vertebral bodies, another clue that the ETT may be in the oesophagus.

Note also the hyperexpanded right upper lobe with pulmonary interstitial emphysema, compressing and collapsing the middle and lower lobes.

Epiglottis

Trachea

Oesophageal intubation: note the ETT again passes into the oesophagus behind the trachea (to right in this radiograph, ‘page down’ to outline, ‘page up’ to remove outline).

The oesophagus here is quite dilated as it is inflated with gas from the ventilation.

Trachea

Oesophagus

The radiopaque ‘blue line’ of a ‘Portex’ blue-line endotracheal tube passes along the long side of the curve of the tube, ending at the mid-point of the bevel. When the head is in the midline, the bevel points towards the left. When strapping an orally inserted ETT, the rule should always be ‘blue line to upper lip’ to maintain safe orientation of the bevel.

The endotracheal tube here has become rotated - look in the white rectangle, and at the next slide. With the bevel pushed up against the tracheal wall, there will be obstruction to exit of gas as the airways constrict in expiration.

The radiograph shows extensive interstitial emphysema, posterior mediastinal air and probably ‘surgical emphysema’ up around the trachea.

Damage to and around the larynx can occur from just a single intubation. Above, a granuloma has formed on one of the vocal cords, and is obstructing respiration. To left, a mucous cyst has formed below the larynx and can be seen in this bronchoscopic view.

The airway of an intubated patient is always irritated. Inflammation shown above comes from suction catheters, and from the endotracheal tube itself. It will be worse if inadequate attention is paid to humidification of the inspired gas.

As well as patchy areas of inflammation in this airway, there is a granuloma of the left main-stem bronchus (see next slide)

This radiograph shows marked hyperinflation of the left lung in this baby who had been intubated for some time. Patchy collapse had been present in the preceding days. Bronchoscopy revealed the granuloma shown in the previous slide.

Suction catheters with side holes (above) predispose to airway trauma, particularly if advanced beyond the tip on the ETT while suctioning.

The catheter shown at left is safer for ETT suctioning - it has no side holes, and has marked graduations so that the catheter can be inserted only to a measured length to allow the the to just protrude through the end of the ETT.

The catheter above was designed to push the mucosa away fro the side holes with its bulbous end. It cannot be made small enough for most ETT sizes used in neonates.

Measured suctioning is possible with graduated suction catheters. In this instance, the cut length of the ETT (12cm) plus 3cm allows the tip of the suction catheter to just protrude through the end of the ETT. If suctioning is done through a manifold, a different measurement needs to be derived by prior assessment.

The hyperexpansion of the right lung in this radiograph was caused by a mucous plug in the right mainstem bronchus. This was able to be aspirated, with return to normal expansion of the lung.

These two radiographs are of the same baby on different days, following extubation after a period of assisted ventilation. The one on the left shows hyperexpansion of the right upper lobe, with compression of the middle lobe and mainstem bronchus, and on the right partial collapse of the right upper lobe, and complete collapse of the middle and lower lobes. The gas in the right mainstem bronchus ends abruptly soon after the tracheal bifurcation.

The radiograph at left could easily be mistaken for a right upper lobe congenital lobar emphysema, if the history was not known. Also, careful examination at that time revealed an audible ‘click’ at the beginning of expiration - the sound of a ‘ball-valve’ mucous plug obstructing expiration.

RWH Brisbane 1996-2000

HMD SpontPNX

VentHMD

VentPNX

<1000 256 2(0.8%)

252 33(13%)

1000-1499

277 6(2%)

229 19(8%)

>=1500 522 92(18%)

360 60(17%)

Other pneumothorax and pulmonary interstitial emphysema illustrations are included under ‘Pneumothorax and other air leaks’ from the main menu’, or click here. Click!

Pneumoperitoneum may also occur as a complication of mechanical ventilation, usually when there is also posterior mediastinal gas present. The left and centre radiographs are of the same patient, supine and erect views, and show also that the gas has tracked into the scrotum via the processus vaginalis. The knob on the end of the umbilical artery catheter is an indwelling continuous measuring pO2 electrode - we no longer use these.

OSTEOPAENIA OF PREMATURITY Follow this group through sequentially by using the left mouse button, page down or down or right arrow, or move directly to

Main Menu

1 Normal bone mineralisation

2 ‘Stage 1’ osteopaenia

3 Vertebral ‘bone-in-bone’

4 Rib fractures with osteopaenia

6 Advanced bone demineralisation

7 Rickets

8 Healing

9 Osteomyelitis

5 Classification/staging of osteopaenia

265-266

268-269

271-272

275-277

10 Thin ribs 278-280

Note the features of the bones in this radiograph of a newly-born appropriate for gestational age (AGA) preterm infant of 27 weeks gestational age.

Well mineralised proximal humeri, and small marrow cavity in humerus.

Well mineralised ribs and vertebral bodies.

Well mineralised iliac wings.

Well mineralised femora, and small marrow cavity in femur.

Nutrient artery in femur

Left:- Lateral view of newly-born baby. Note particularly the well mineralised vertebral bodies.

Above:- Care needs to be taken in viewing the long bones. The left humerus viewed obliquely above may appear to have some demineralisation at its proximal end, but the right one viewed as a straight AP view is seen to be fully mineralised.

At 10-14 days of age, the bones are seen to be losing mineral, initially from the ends of the long bones. This has been classified as ‘Stage 1 osteopaenia’.The iliac wings also undergo similar demineralisation seen around their superior edges (below), and the same occurs around the medial edges of the scapula.

Stage 1

‘Stage 1’ demineralisation of vertebral bodies appears as a ‘bone-in-bone’ appearance with a well-mineralised centre surrounded by a halo of poorly mineralised bone and some sub-periosteal mineralisation still present.

Stage 1

This radiograph showing demineralisation at the ends of the femur, tibia and fibula was taken at birth - it is very uncommon to see this sort of demineralisation at birth, but it may occur in instances of poor intrauterine nutrition such as severe intrauterine growth restriction, or, as in this case, rhesus disease with placental hydrops.

With further demineralisation, spontaneous fractures may occur, most commonly in the ribs, seen above in the 5th-7th, and possibly 8th, ribs on the right. Note the poorly mineralised scapulae and ribs in this baby. Long bone fractures are less common, but do occur.

Stage 2

Classification of Osteopaenia of Prematurity*

Stage Duration (days)

Definition Incid-ence

Age detected (days)

1 10-60 Demineralisation in metaphyses of long bones and in the margins of other bones

100% 24 (7-58)

2 20-80 General demineralisation. Fractures May be seen

67% 40 (20-78)

3 60-100 Active Rickets 44% 83 (54-103)

4 70-140 Healing rickets – (17% showing only subperiosteal changes)

61% 84 (68-113)

* See Masel et al: ‘Osteopaenia and rickets in the extremely low birth weight infant’Australasian Radiology Vol XXVI, No. 1, 1982Based on findings in 25 ELBW infants who survived >28 days

Osteopaenia of Prematurity

• Osteopaenia of prematurity was reported with increasing frequency in the late 1970’s and early 1980’s. It has subsequently been shown to be due to mineral deficiency in the diet or parenteral nutrition of small preterm babies. Human breast milk fed at 200mls/Kg/day provides approximately 1 mmol/Kg/day of phosphorus, and 1.5 mmol/Kg/day of calcium, whereas a fetus in mid-trimester accumulates approximately 3 mmol/Kg/day of each of P and Ca.

• Babies exhibiting rickets in these circumstances typically have low [P] (a pre-requisite of all rickets), and high levels of 1,25 dihydroxy vitamin D, and high ALP.

• Provision of extra minerals (Ca and P) in the diet, in the form of human milk fortifiers and ‘low birth weight’ artificial formulas, has seen the elimination of the most severe manifestations of osteopaenia, such that frank rickets and fractures are rarely seen now.

In advanced stages of demineralisation, the vertebral bodies lose their ‘bone-in-bone’ appearance and take on a form of ghost outline of the original dense bone, and rib ends may become splayed (see right).

Stage 2

Sometimes signs of frank rickets may be seen, with demineralisation, irregularity and splaying of metaphyses, and bony spicules at metaphyseal edges giving an appearance of metaphyseal ‘cupping’. These signs are illustrated in distal femur, proximal tibia and fibula in the radiograph at left, and distal radius and ulna below. There is also a characteristic soft tissue bulge at the wrist below, caused by proliferation of demineralised osteoid.

Stage 3

When remineralisation occurs, a dense band appears at the metaphyses, seen here in distal radius and ulna, and at the splayed ends of the ribs, and in subperiosteal regions (next slide).

Stage 4

Subperiosteal new bone formation occurs as poorly mineralised osteoid becomes mineralised, in these cases healing of frank rickets.

Stage 4

Osteomyelitis of the right tibia (at left) with Staphylococcus aureus is a florid disease and in the newborn typically involves the whole bone, and often joints above and below as well.

The right upper femur and hip involvement with MRSA (above) is less aggressive, and presents as a rather indolent infection which may be difficult to diagnose.

The small lung fields and very thin ribs in this baby give a clue to a diagnosis of congenital weakness (fetal bones thicken because muscles pull on them, and therefore are thin when muscles are weak; fetal lungs grow in part because of fetal breathing movements), most

commonly myopathy - e.g. dystrophia myotonica, myotubular myopathy, etc. In this case, a definite diagnosis of dystrophia myotonica was made, and the diagnosis also made in this

baby’s twin and the mother, who was symptomatic but not previously diagnosed.

This baby’s thin ribs were due to a chromosomal abnormality - Trisomy 18, another recognised cause of thin ribs

Babies with thin ribs usually have thin long bones also. In this case all were extremely thin, and prone to fracture as seen in these fresh fractures of the right humerus, both

femurs and left tibia from delivery. This family have subsequently had two more babies with this same condition, diagnosed as ‘lethal gracile bone dysplasia’

Take a careful look at these abdominal radiographs, and decide if you can see any pneumatosis intestinalis - does this child have NEC?

The answer is no! (You probably guessed). All of the gas bubbles which look like pneumatosis intestinalis in the radiograph at left are in faeces. Look particularly around the curve of bowel wall

beneath the liver - it is very clear and ‘clean’. If this were pneumatosis, you would expect to see ‘tram tracks’ (train lines?) of shadowing of serosa, pneumatosis, oedematous mucosa, intestinal gas. At right, the apparent circle just below the right lobe of the liver is formed by bowel wall, intraluminal gas, then faeces. This interpretation is not easy - it was misinterpreted at the time and the baby

subjected to laparotomy, which revealed normal bowel and ‘inspissated milk syndrome’, with a large amount of thickened altered milk extruded from the affected bowel. It was also not benign, as a

post-operative septicaemic event resulted in death.(See next slide for NEC / non-NEC comparisons)

Serosa

Intraluminal gas

Gas in faeces

Intraluminal gas

Intramural gas (pneumatosis intestinalis)

Oedematous mucosa

Oedematous serosa

Not NEC

Intramural gas (pneumatosis intestinalis)

Portal venous gas

The gas bubbles here in the right side of the abdomen are in meconium. The baby had delayed passage of meconium, and then passed a meconium plug. Diagnosis was ‘hypoplastic left colon’

after contrast enema.

The lateral radiograph at right helps interpret the ill-defined shadow in the right chest in the AP film at left - an anterior eventration. If associated with significant respiratory distress, surgical repair may be

advisable.

The gas shadows in the chest of this patient can be seen to arise centrally, and represented an intrathoracic stomach, which herniates up through a enlarged oesophageal hiatus.

How do you interpret the shadow confluent with the right heart shadow here?(see next slide)

Look carefully at the soft tissue shadow on the back of the patient seen in the lateral view - it was a large haemangioma. (left click or page down)

Some central venous catheters are ‘radio-opaque’, but it remains our policy at RWH to inject these with dye for x-ray to determine tip position. We also maintain some infusion of dye while the x-ray is taken, resulting in a small blush of dye coming from the end of the catheter - that way there is no doubt about the tip position, and you can see if the catheter tip is in a small vessel, or up against the wall of the atrium.At left above is a dye-injected ‘radio-opaque’ catheter , with its tip clearly in the SVC. At right is the same baby, with the catheter in the same position but not injected - note that once the catheter enters the SVC in the mediastinum, the exact position of its tip cannot be determined. The abduction of the arm will pull the tip out slightly (see Nadroo et al, Pediatr 110:131-136 (2002)), but it is still not clear exactly where the tip is.

Similar to the previous slide, the catheter in the radiograph at left is a dye-injected ‘radio-opaque’ catheter, with its tip low in the right atrium. It was pulled back 1cm to place its tip in the top of the right atrium. On subsequent plain x-ray, note that the catheter can probably be seen entering the SVC (yellow arrow), but its tip is not at all clearly visible. It is unwise to rely on uninjected x-ray examination of silastic/silicone central venous catheters to determine tip position.

Umbilical venous catheter tips also migrate inwards after being inserted, so it is worth re-x-raying the day after insertion to be sure position is maintained. You frequently need to pull the catheter back 1-2cm the second day. It is presumed this is because the course of the umbilical vein is curved in an AP direction, and straightens as the gut fills with gas. The catheter illustrated at left above was considered to be appropriately placed, with its tip right where the IVC enters the right atrium. The following day, with its position at the umbilicus firmly tied and unchanged, the tip was in the left atrium, and needed to be pulled back 2cm. These catheters also move in and out with changes in abdominal distension – if the catheter is inserted when the bay has marked abdominal distension (e.g. has hydrops or a congenital gut obstruction), it will migrate in if the abdominal distension is relieved, and needs then to be reviewed.

This radiograph was taken on the second day of life of this 35 week infant. Note the segmental collapse in the right upper lobe, and more subtly, but importantly the hyperinflation notable over both diaphragms. The following day, after some treatment with CPAP, the opacity in the right upper lobe was gone, and the

hyperinflation was less. The baby, however, was intolerant of removal of the CPAP, developing severe respiratory distress when it was removed. Bronchoscopy showed severe bronchomalacia of all airways

beyond the trachea, and long-term management with naso-pharyngeal CPAP was required.

Right lobe of thymus

Left lobe of thymus

Mediastinal pleura

Anterior pneumomediastinum lifting both lobes of the thymus from the heart. The right lobe of thymus is unusually large and

extends unusually low here - enough to confuse some into thinking it to be an upper lobe pneumonia. Press the right arrow to see descriptions of the features outlined, left arrow to remove the outlines. In the radiographs at right, taken over subsequent days, note the thymic lobes progressively settle back onto the heart as the mediastinal gas reabsorbs. There may a small L

pneumothorax also. Note also the circular incubator shadow in the first radiograph, overlying the stomach and L hemidiaphragm.

Sternal segment

Sternal segments

The gas shadow (yellow arrows) shown here was present soon after uncomplicated intubation at birth in this baby, extending from vertebral level T5 to the base of the skull. It enlarged over subsequent days, and the baby was unable

to swallow secretions, requiring frequent oral suctioning. Lateral radiograph shows it to be retropharyngeal, and CT scan showed it to be separate from and behind the oesophagus. Oesophagoscopy revealed a healing lesion in the mid-

oesophagus posteriorly, believed to a healing perforation, source unknown. In the two later A-P radiographs, there is a gas shadow within the cardiac shadow, in the position typically seen with posterior mediastinal gas. A drain was inserted via the

pharynx, removed a few days later, and the gas collection did not recur.

The End EXIT

Main Menu

This central venous line has its tip in a very unusual position – if it were not injected with dye, it could well be assumed to be in the SVC. The dye however outlines some very small vessels, presumably vasa vasorum of the SVC – this would not be a good place to infuse hypertonic

parenteral nutrition solution. It was pulled back and used without complication.

These two central venous lines outline hepatic veins. The one at left outlines a hepatic lobule, and dye tracks back past the catheter into the IVC and right atrium. On the right, the tip is probably in the hepatic vein and dye tracks down into hepatic vein branches within the liver, and back into the IVC. The exact catheter tip position is not visible in either instance because of the amount of dye

tracking back past the catheter, and the catheter should be pulled back and re-injected for tip localisation.

The pattern of dye at the tip of this CVL shows it to be up against the wall of the right atrium in the right atrial-right ventricular junction, and the catheter is looped in the right atrium. It was pulled

back, but only a sufficient distance to undo the loop, not shift the tip. The baby suffered an episode of pulmonary haemorrhage and bradycardia 8 hours after catheter insertion, and the catheter was then pulled back a further 2cm, with no further problems. There was a pericardial effusion present

on cardiac echo 2 days later, which resolved spontaneously. Great care must be taken when assessing distances in a catheter loop, as in the 2-dimensional x-ray the orientation of the loop is

not known, and measurements will be accurate only if the loop lies parallel to the x-ray plate, which would rarely be the case. It is easy to underestimate the length of catheter in a loop needing to be

pulled back.

(Page up or left arrow will remove the yellow arrows, Page Down or right arrow will restore)

Free gas

Falciform ligament

Free gas trapped under

falciform ligament

Look for signs of free gas in these abdominal radiographs, then press ‘page down’ or right arrow to see annotations, ‘page up’ or left arrow to remove annotations.

The pattern of dye at the tip of the CVL in the radiograph at left shows it to be resting on or near the tricuspid valve. This is not a safe position to leave it, and it should be pulled back.

The radiograph on the right shows a catheter with its tip in the SVC, with dye streaming from the end of it entering the right atrium. The tip is the point where the radiopaque line thickens at the bottom

of the 5th rib. This is a safe and adequate position for the catheter tip.

NOT HERE

It is MUCH easier to get the catheter tip anterior to the lung if you enter the skin near the anterior axillary line as shown

The sudden onset of respiratory distress in any baby with a CVL in place must be taken seriously and assessed carefully and urgently. Pleural (as above) or pericardial extravasation of fluid may be life-threatening. The above pleural fluid was swiftly and easily drained by needle thoracocentesis – 25mls of milky parenteral nutrition fluid was obtained, with immediate relief of the baby’s respiratory distress. The catheter tip had been shown by contrast injection to be where it appears in this film (yellow arrow) – interpreted as in the SVC

Interpretting Neonatal Xrays [Click Enable Macros]

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