BMT 2012 Clinical CT Applications

8/2/2019 BMT 2012 Clinical CT Applications

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Wim Tukker systeemspecialist CT UMCG

Imaging Techniques in Radiology: CT


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Ch 13. Computed Tomography13.1 Explain basic principles13.2 Explain geometry and historical development13.3 Understand detectors and detector arrays13.4 Explain slice thickness, pitch

13.5 Explain tomographic reconstruction process13.6 Understand digital image display13.9 Explain artifacts

End terms for Imaging Techniques in Radiology

Following the book The Essential Physics of Medical Imaging 2nd ed byBushberg et al.

Know -> Understand -> Explain(Read), (optional)


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What to expect?

- CT in Archeology

- CT in Cardiology

- Clinical CT applications: head and neck

- CT Techniques

- Cone Beam CT

- CT in Forensics (CSI-Groningen)

- Clinical CT applications: chest and abdomen

- Radiation dose

Monday26 march 2012

09.00 12.00 h

Thursday29 march 2012

13.00 16.00 h

- Dual Energy CT

- CT Techniques


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What to expect?

- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 2012

09.00 12.00 h


13.00 16.00 h

- Dual Energy CT

- CT Techniques


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Siemens Somatom Sensation-16 Siemens Somatom Sensation-64 (2x) Siemens Somatom Definition (Dual Source)

CTs in UMCG: Radiology, Nucleair Medicine & Radiotherapie

Siemens Biograph 64 slice mCT (PET-CT) Siemens Symbia 2 and 16 slice SPECT-CT Siemens Sensation Open


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Toshiba

AquilionONE

Brilliance iCTPhilips

SiemensDualSource Defini

tionG.E.

CT750HD


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Conventional tube diagram

Straton X-ray tube diagram(Sensation 64 and Definition)

Cooling rate 5 MHU/min


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Double z-Sampling: two focus spots alternating 4.640 per second

Straton X-ray tube design


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0.4 x 0.4 x 0.4 mm isotropic resolutionDouble z-Sampling:

Sensation 64, Definition


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Adaptive Array Detectors

Thin collimation platesCeramic scintillationmaterial (solide state detector)Very short after glowing time (gadolinium oxi-sulfide) < 0,00043 sec!Photodiode-array

Configuration detector system Sensation 64 and Definition (A-tube)

4x1.2mm

32x0.6mm

4x1.2mm

24x1.2 >

28.8mmZco

verage

CT technique

page 339 - 342Bushberg,


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Sensation 16

24 rows of detectors16.128 elements1.344 canals per slice

Max. 2320 projections each 360

Sensation 64 and Dual Source

40 rows of detectors (DSCT 2x, A and B)26.880 elements (DSCT system B 14.080)

21.504 canals per slice (DSCT system B 11.264)Max. 4608 projections (views) each 360

Configuration detector system Sensation 64 and Definition (A-tube)

CT technique



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Sensation-16: 24 detectors on row!

8 x 2.7 mm + 16 x 1.35 mm: true detectorwidth!

eff. slice-thickness

Collimation: principle



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Pitch: table feed per rotation / total width of collimated beam

E.g. table feed 12 mm, collimation 16 x 0.75 > beam pitch 1

Table feed: per rotation

E.g. table feed 9.6 mm/rotation, collimation 64 X 0.6 (32 x 0.6=19.2 mm) > pitch 0.5

Pitch en Table Feed

Effective mAs

mA.s produkt remains equal.

E.g. Increasing pitch > shorter scantime > more mA.

E.g. Decreasing rotationtime > longer total scantime > less mA.



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Is there influence of the pitch on the slice

thickness?

Is there any influence of the pitch on the spatialresolution?

Pitch

Effective mAs (radiationdose) stays equal.



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What to expect?

- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h


13.00 16.00 h

- Dual Energy CT

- CT Techniques


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Guidelines for radiology report

Increased brain pressure? Brain shifting?

Bleeding? Differences in density? Abnormalities: localisation, size and number? Fractures? Bone destruction?

Protocol CT-scan Brain

Indications

Standard

Trauma Tumor or abces (MRI preferred) Metastases (MRI preferred) Stereolithography Navigation (stereotaxie)Radiation-dose 1.1 mSv

CT-scan Brain


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CT-scan Brain sequential or spiral?

OMAxial view in spiral CT(source images)

MPR in OM-direction(Orbito-Meatal)

MPR; Multi PlanarReconstruction



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X-Y: 5 mm/index 5 mm

(sequential)

Z: 5 mm/index 5 mm

CT-scan Brain sequential or spiral?

Z: 3 mm/index 1.5 mmpage 371 - 372

Partial Volume Effect

Bushberg,


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ICH

IntraCranial

Hematoma

3D

CT-scan Brain, examples

Stroke!

Most common question:

Bleeding or no-bleeding?

No-bleeding > start

- Anti-thrombolytic drugs- Antiplatelet medicine like

Aspirin

?


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CT withIV-contrast:

100 mlVisipaque 320

Abces

MRI-FLAIR MRI-T2MRI-T1 MRI-T1 + gado


?


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Vasculitis (inflammation)?

white and grey matter

oedema

Same patient: possible cause of the abces?



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MPR Transversal MPR Coronal

Transversal Coronal

Spiral CT of maxillary sinus (NBH)

Radiation-dose 0.2 mSv


MPR


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MPRThickening of mucus



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B-cell lymphomaAdvantage CT: superior bone/air visibility, why?


MPR



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Advantage MRI: superior soft tissue visibility

Same patient, MRI



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Coronal

Coronal

CoronalCoronal

Axial

On a sagital imageMPR // canalis facialis

Spiral CT of petrosal bone (mastoid)

MPR perpendicularto canalis facialis




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Anatomy

Axial (transversal)

Spiral CT of petrosal bone (mastoid)



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DSA versus CT (coronal MIP)

Golden standard

?

S i l CT f b i t i (CTA)


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Spiral CT of brain arteries (CTA)


I.V. contrast: Visipaque 320; 80 ml with flow 4 ml/sec.

Start scan manually!

1 3

4 5

2

6



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Scan in 10 15 sec.

Advantages CTA: Non-invasive, short scanning time with onlimited 3D processing.


page 361Bushberg,



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Candidate for coiling procedure?

Top of basilar arterie


page 361Bushberg,

One Stop Diagnose CVA


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One-Stop Diagnose CVA

?

Unwell with left hemiparesis: infarction right hemisphere?

Entrance

One-Stop Diagnosis CVA


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CTA VRT Day 3 Day 30CTA MIP

Perfusion-CT

Entrance

One-Stop Diagnosis CVA

Unwell with left hemiparesis: infarction right hemisphere?

Traumatology


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Technique: VRTHit by a baseball pole-axe

Traumatology

Bushberg, page 360-362

T itiTraumatology


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Trauma capitis

SSD

VRT

Traumatology

?


(s ti t)Traumatology


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(same patient)Traumatology

Take Home Message: always start with looking at source images (first reconstruction)


Traumatology


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More metal artefacts

um gy

Traumatology


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By courtesy of Dr. J. Wildberger and Dr. A. Mahnken, University of Aachen

Future: further reduction of metal artefacts

gy

Traumatology


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Movement artefacts

gy

?

Traumatology


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Gunshot

?


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Protocol CT-scan Neck

Indications

Standard Oncology

Trauma CTA

(Hernia to MRI)

Guidelines for radiology report

Soft tissue evaluation. Pathology?

Nodules, glands? CTA: stenosis? CTA: aneurysm? Fractures? Bone destruction?


CT neck with contrast


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Maligne lymfoma with necrotic lymph gland.

Hindering metal artefacts

Future: Iterative reconstruction, less artefacts and lower dose!

Partial Volume effect


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Enlarged thyroid: problems with swallow

MPR coronal direction: 1, 3 - 5 mm slice thickness

Partial Volume effect: sharp versus unsharp, noisy versus a better S/N ratio

MPR 1 mm MPR 3 mm MPR 5 mm


Traumatology


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Wear, (slijtage)

Traumatology


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Fracture second Cervical Vertebra

Traumatology


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Fracture 3th Lumbar Vertebra

Traumatology


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Fracture 2th Lumbar Vertebra (near to transverse lesion)

Same patientTraumatology


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p

Report after 2 years: no complaints, no limitations


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Break


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What to expect?

- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h

Thursday29 march 201213.00 16.00 h

- Dual Energy CT

- CT Techniques

Cardiology


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Fly Through (RCA)

2002 Sensation-16!

Cardiac Imaging = need for speed !Cardiology


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CTA: image quality is inversely proportional to the heartrate

g g p

R R R R

Faster scanning = higher temporal (time) resolution

Two possibilities:decrease scantime or the heart rate (> 70 bpm beta-blockers)

- Rotationtime of 500, 420, 370 up to 270 ms (limitation by G-forces)

- Half-scan reconstruction (180 degrees): 250, 210, 185 up to 135 ms

Aquisition methodes for CTA in SSCT or DSCTCardiology


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Applications: Coronary Arteries, Cardiac Function, Valves, Bypass

q

1. Spiral (retrospective, with ECG-pulsing)

- Classic method for CTA (all vendors)

Advantage:- Phase shifting possible (with wide pulsing)

- More phases to use in Cardiac Function

Disadvantage:- Radiation dose between 8-15 mSv (or even higher)

Multislice Spiral Single Source CT

Cardiology


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Image data

DelayReco

n

Reco

n

Reco

nReco

n

Continuous

spiralsc

an&feed

z

-Position

Time Half scan segment

Raw Data plus recorded ECG-signal (retrospective reconstruction).

Reconstruction: delay in percentage or time in msec (e.g. start at 75 %).

p g

180 degreesreconstruction

Siemens

Multislice Spiral Single Source CTCardiology


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Time

Volume Gaps

Delay

Reco

n

Reco

n

Reco

n

Reco

nContinu

ous

Spiral

Scan&

Feed

z

-Position

Very low heartrate or table feed (pitch) to high: gaps!

Half scan segment

180 degreesreconstruction

Siemens

Cardiology


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Gaps in a 16-slice CT

Single Source CT

Cardiology


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Single Source CT

Temporal resolution of maximum 165 ms

= 165 msRotation Time

2

Temporal Resolution =

Single Source CT 180 degrees recon

Cardiology


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Single Source CT 180 degrees recon

Technical challenge with high heart rates

60 bpm 100 bpm

Comparison between Single Source and Dual Source CTCardiology


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Siemens SomatomSensation-64 Cardiac(Single Source)

Siemens Somatom Definition(Dual Source)

Cardio-imaging: high temporal- and spatial resolution

Dual Source CT: principle

Cardiology


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Dual Source CT: principle

Normaly only 1 tube (Source) is used for scanning (A-tube, Single Source)

Dual Source CT

Cardiology


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Dual Source CT

Heart rate independent temp. resolution of 83 ms

= 83 msRotation Time

4

Temporal Resolution =

Dual Source CT

Cardiology


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Dual Source CT

Reliable imaging of all heart rates

60 bpm 100 bpm

Aquisition methodes for CTA in SSCT or DSCTCardiology


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move move move

Applications: Non-Coronary (e.g. RF Ablatio), Calcium Scoring

2. Sequential (prospective, step and shoot)

- Alternative method (reducing radiation)

Advantage: radiation dose between 2-4 mSv- Calcium Scoring between 0.8 and 1.5 mSv

Disadvantage: no phase shifting possible,- only in future Cardiac Function possible- sometimes steps between slices

Prospective Sequential (Step and Shoot)Cardiology


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1 2 21

+ =

- Sometimes steps between slices

- Higher heartrate: bigger and more

steps

- Use betablockers to decreaseheartrate and steps

Prospective Sequential (Step and Shoot)Cardiology


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- Sometimes steps between slices

- Higher heartrate: bigger and more

steps

- Use betablockers to decreaseheartrate and steps

Timing of contrastCardiology


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Test bolus

Bolus tracking manual

- place of ROI:outside the patient in air or fat

Standardised automatic BolusTracking

- place of ROI:Descending AortaThreshold 100 HU

Advantage:less movement, less artefactscompared to Ascending Aorta,operator independent

manual

2 cm below the bifurcation of the trachea

Cardiac contrast protocols (UMCG)Cardiology


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Contrast: Iomeron 400

Injector: MedRad Stellant, Sensation-16 and Sensation-64

Contrast Saline (NaCl)

ml/sec ml ml/sec ml

Cardiac spiral 3 3

and sequential 5 80

Biphasic 4 20 4 50

Cardiac-bypass 3 3

Extra series 5 60 4 30

Contrast: Iomeron 400

Injector: MedRad Stellant, Dual Source CT

Contrast Saline (NaCl)

ml/sec ml ml/sec ml

Cardiac spiral 3 3

and sequential 5 65

Dual Flow 4 80(30-70%) 4 30

Cardiac-bypass 3 3

Extra series 5 60 4 30

Timing of the reconstruction (spiral mode)Cardiology


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5 %10 %

15 %20 %25 %

30 %35 %40 %45 %50 %

55 %60 %

65 %70 %75 %

80 %85 %90 %

95 %100 %

Manual or automatic (best phase)

Start phase 65 % 70 %

75 % 80 %

85 bpm > 65-70%

85 bpm < 30-35%

CaseCardiology


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Male, 57 y Chest-Pain on ER > 50% stenosis & complete occlusion RCA

LCX LAD

No significant stenosis

Dual Source CT > CAG > PTA

Retrospective spiral CTA with ECG-Pulsing30-80% full dose, rest 20% dose

Start phase reconstruction 70%

RCA

Cardiac Function EvaluationCardiology


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epicardium

endocardium

Do not include the pappilary muscles!

Systolic phase

Diastolic phase

- Recommanded: 20 Phase reconstruction

- 2 mm, index 2 mm (256 matrix if possible)

CaseCardiology


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Siemens CirculationEvaluation Program

Wall thickness ES Wall thicknessED

Wall thickening Wall motion

Aorta ValvesCardiology


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Recommanded:- 20 Phase recon,

1 mm, index 1 mm (512 matrix)- Kernel medium/sharp- No ECG-pulsing (3-6 mSv)

What to expect?


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- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h


- Dual Energy CT

- CT Techniques

Dual Energy CTDual Energy


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Dual Energy is based on the unique energy dependant attenuationprofiles of different sorts of tissue like fat, soft tissue, bone and contrast.

Dual Energy


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Thomas Flohr, First performance evaluation of a DSCT; Eur Radiology (2006)

Dual Energy is based on the unique energy dependant attenuationprofiles of different sorts of tissue like fat, soft tissue, bone and contrast.

Dual Energy

Determination stones in kidney


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Anno Graser MD et all (Mnich-Grosshadern)


Dual Energy



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Uric acid-stones (9%) Calcium oxalate-stones (80%)

Anno Graser MD et all (Mnich-Grosshadern)

D t rm nat n st n s n n y

Dual Energy


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Bone Subtraction

Christoph Becker MD et all (Mnich-Grosshadern)

Evaluation Myocard Perfusion with DE Perfusion CT

Dual Energy


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Ischemia

- Anatomy- Function- Perfusion

Dual Energy:

Dual Energy


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Possible applications

- detection of inflammation, e.g. in softplaques

- differentiation between cartilage, tendons and ligaments(traumatology)

- differentiation between benign and malign nodules, cystsand other abnormalities

- simply removing of bony structures and calcification by way of subtraction- differentiation in composite of kidneystones

- virtuel reconstruction of a native series

Developments in Dual Source CT

What to expect?


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- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h


- Dual Energy CT

- CT Techniques

Mummie Janus (RMO)

Archeology


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AZG

1973

Egyptologist Dr. H. te VeldeMedical student T. Valke

Archeology


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1998 Mummie Janus

1998 Mummie JanusArcheology


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hart

Archeology

Unit of Art in Medicine, Manchester;Facial reconstruction made by Denise Smith and Caroline Wilkinson.


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Unit of Art in Medicine, Manchester;Facial reconstruction made by Denise Smith and Caroline Wilkinson.

Archeology


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1 juni 1999 disclosure of the reconstructed head by the actingrepresentative Egyptian ambassador, mr. Ashraf Elkholy.

Archeology


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1 juni 1999 disclosure of the reconstructed head by the actingrepresentative Egyptian ambassador, mr. Ashraf Elkholy.

Archeology


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Corpse preserved in peat (veenlijk)

Archeology


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Meisje van Yde

Museum-Assen

M i j Yd

Archeology


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Meisje van Yde

But is it reliable?

Tarbot


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END

Imaging Techniques in Radiology: CT


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Wim Tukker systeemspecialist CT UMCG

What to expect?


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- CT in Archeology

- CT in Cardiology


- CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h


- Dual Energy CT

- CT Techniques

Each individual projection gives acontribution to the eventual

Image Reconstruction: Backprojection


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In practise we look more to the pixelsthen to voxels.

Realise that a pixel is always anaddition of a volume.

In an other way: a pixel is a 2-dimen-sional display of a 3-dimensionalemeasurement.

Voxels en pixels.

Each individual projection gives acontribution to the eventualpicture advancement (beeldopbouw).

level 40window 400

level 40window 400

CT Chest


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HU: Hounsfieldschale

level - window

level 40window 800

level - 650window 1600

CT technique Bushberg, page 358

Daily calibration of the CT


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Matrix


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Backprojection: filtered (Kernel)


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1 pixel (voxel)Matrix in CT: 512x512

CT technique Page 352 - 355

Influence Kernel on Sharpness


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Influence Kernel on Noise


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Spatial resolution


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10 mm low Kernel (filter) 5 mm low Kernel

2 mm with a spatial filter (1H)

CT technique Bushberg, page 352 - 355


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Effect of the kernel


contrast resolution

(chicken)


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(bacon rag)

(steak)

(chop)

( )

(wood)(stone)


spatial resolution


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Influence Slice Thickness on Spatial Resolution


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Partial Volume Effect

Spatial resolution Contrast resolution

CT technique


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smal details

- interstitial lungtissue- Inner Ear structures- Temporal Mandibulair Joint

contrast

- braintissue

- abdominal organs, liver- bloodvessels, lymphnodes

method

- thin slices- higher kV- lower radiationdose- sharp kernel- wide window

method

- thicker slices- lower kV- relative higher dose (Alara)- soft kernel- small window


What to expect?

- CT TechniquesMonday


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- CT in Archeology

- CT in Cardiology


CT Techniques

- Cone Beam CT



- Radiation dose

Monday26 march 201209.00 12.00 h


- Dual Energy CT

- CT Techniques

CT Chest

Difference between X-Ray and CT Scoutview?


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Scoutview A.P.

Fan beam

projection

Bushberg, page 330

Ascending Aorta

Window level: mediastinum-settingCT Chest


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Pulmonary Artery

Superior Vena Cava

g

Descending Aorta

Pleural Effusion

Bushberg, page 358

Window-level: lung-setting

CT Chest


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Bushberg, page 358

Lung Metastasis

CT Chest


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CT Chest


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HD

DiaphragmaticHernia

Curved MPR


Carcinoma of the Oesophagus

?

CT Chest


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Gastric tube

CT Chest


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Atherosclerosis

Heavy smoker, 67 y

Coughing, blood

CT Chest


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First visit jan 2005

Next visit sept 2008

CT Chest


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Lung carcinoma with hilair adenopathy (lymphoma)

VRT (Volume Rendering Technique) usefull or not?CT Chest


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Virtual scopy: usefull or not?

CT Chest


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VirtualScopy

Future: evaluation long embolia with Dual Energy Perfusion CT

CT Chest


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CT Chest


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Stent control thoracic aneurysm

Pancreas

Stomach

CT Abdomen


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Superior Mesenteric Artery

Spleen

Kidney

Adrenal

Diaphagm

Liver

Gallstones

Abdominal anatomy

Determination of a heamangioma of the LiverCT Abdomen


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Four fasic Liver CT

CT Abdomen


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Protocol living kidney donation

CT Abdomen

Evaluation The Urological System: Ureters; Urinary Bladder;


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Protocol living kidney donation

Intra-Uterine Device (IUD).


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Abdominal Aortic Aneurysm

CT Abdomen


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CT Trauma

Polytrauma


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ATLS trauma-scheme

X-thorax (chest)X-cervical spine lateralX-pelvis

CT Trauma


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X-pelvis

- clavicula #- ribfractures- trace fluid right- femur #

Ultra-sound of the abdomen

- fluid in the chest- fluid around spleen and liver

CT Trauma


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CT or Operation Room?

-> CT!

CT Trauma


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- ventral pneumothorax *)

- heamatothorax, right side

- multiple ribfractures *) *) Artificial respirating

CT Abdomen (arterial phase)

- Rupture of the spleen- Active arterial bleeding- Fluid round the organs

CT Trauma


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Operation Room? No!

CT Trauma Groin; liesstreek


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DSA (DigitalSubtractionAngiography)

- Arterialextravasationfollowed byembolisation

CT trauma

First take away the lifethreatening situations!


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DSA

- Embolisation; glue procedure

(artificial infarct)

- Clavicula #

CT Trauma

Collateral damage


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MPR

(Multi PlanarReconstruction)

MIP(Maximum IntensityProjection)

# Cervical 2

CT Trauma


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Collateral damage

Break


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What to expect?


- CT TechniquesMonday26 march 201209.00 12.00 h


139/180

- CT in Archeology

- CT in Cardiology

- Cone Beam CT



- Radiation dose


- Dual Energy CT

- CT Techniques

S/N


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165 mAs

20 mAs 20 mAs

165 mAs

Optical Magnification

Effect mAs on image quality

CT fysics


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20 mAs 110 mAs

Object attenuation

Radiation-protection in CT: AEC (Automatic Exposure Control)

Automatic adaption mA (tube current) to the shape (reference

detectors) of a patient in the XY-axis (up to Sensation-16).

CT fysics


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LOW attenuation

High attenuation

Scantime in ms0 500 1000 1500 2000 2500

0.25

0.50

0.75

1.0

0

Modulated tube currentlateral

a.p.

Round objects, no reduction!

Thick patients, children

Bushberg, page 366

with AECstandard scan

Radiation-protection in CT: AEC (Automatic Exposure Control)

CT fysics


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189mAs, noise = 9.4HU199mAs, noise = 12.9HU

Bushberg, page 366

Care Dose 4D

CT fysics


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Real-time tube current adaption: up to 66 % dose reduction compared to fixed mA!

Sensation 64, Dual Source

Bushberg, page 366

Optimal image quality, dose adapted to anatomy

CareDose 4D

CT fysics


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55mAs

130mAs110mAs

140mAs

Bushberg, page 366

Absorbed dose: deposited energy in tissue (mGray)

Equivalent dose: biological effects in relation to the sort of ionising radiation

CT fysics


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(mSv) X-rays = factor 1 (protons = 5, neutrons = 5-20, = 20)

Effective dose: cumulative weighted organdose (mSv) > cancer risk.

Effects: stochastic > no borderline, proportional to dose> tumorinduction and genetic damage

Effects: deterministic > borderline> cataract, infertility, skin damages

Bushberg, page 362 - 366

CTDI = Computer Tomography Dose Index

Step one: calculating absorbed dose in mGray

CT fysics


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A measurement for radiation absorption is CTDIw (mGray).CTDIweighted = 1/3 x CTDIcenter + 2/3 CTDIskin.

D.L.P.

CT fysics


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The Dose Length Product says moreabout the total amount of absorbeddose.

DLP = CTDIw x st x n (multiply)

st = slicethickness, beamwidth inZ-axis

n = number of adjusted slices or

rotations


CT fysics


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Effective dose (E) in mSv: radiation risc for the patient

Definition organdose: average absorbed energy per organ(mGray). E = total organdose (mSievert)

CT fysics


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HT = Absorbed organdose x quality factor (1)

WT= Organ weighted factor (ICRP 60*)

E = WT x HT

* International Commission of Radiological Protection


Nucleair attack onHiroshima 6 aug 1945 andNagasaki 9 aug 1945

CT fysics


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Japan: Hiroshima

Total number of DeathsImmediately: 78.000End 1945: 140.0002004: 237.062

Table. Numbers of cancer deaths by cancer type andstrength of evidence for a radiation effect.

____________________________________________________________________

Site Total Estimated Evidence for Site Total Estimated Evidence forDeaths Excess Effect Deaths Excess Effect

Organ sensitivity after the A-bom radiation, Hiroshima(RERF, Radiation Effects Research Foundation)

CT fysics


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Deaths Excess Effect Deaths Excess Effect____________________________________________________________________

Stomach 2529 65 strong F. Breast 211 37 strong

Lung 939 67 strong Ovary 120 10 strong

Liver 753 30 strong Bladder 118 10 strong

Uterus 476 9 moderate Prostate 80 2 weak

Colon 347 23 strong Bone 32 3 moderate

Rectum 298 7 weak Other solid 948 47 strong

Pancreas 297 3 weak Lymphoma 162 1 weak

Esophagus 234 14 strong Myeloma 51 6 strong

Gallbladder 228 12 moderate

Weightfactors for calculation of the

effective (organ) dose.

Weight factors: ICRP-norm

Absorbed dose (mGy) > organdose (mSv)

CT fysics


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(ICRP #26, 1977) (ICRP #60, 1990)

Gonads 0,25 0,20Bone Marrow 0,12 0,12Colon - 0,12Lung 0,12 0,12Stomach - 0,12

Bladder - 0,05Breast 0,15 0,05Liver - 0,05Oesophagus - 0,05Thyroid 0,03 0,05Skin - 0,01Skeleton 0,03 0,01Remainder 0,30 0,05

Sum 1,00 1,00

What to expect?

- CT in Cardiology




154/180

- CT in Archeology

CT in Cardiology

- Cone Beam CT



- Radiation dose


- Dual Energy CT

- CT Techniques

Disadvantages 3D to 2D

Cone Beam CT


155/180

NEVER BELIEVE AN X-RAY

2006


156/180

NewTom 3G DVT

i-CAT Cone Beam 3-DImaging System

A Clear Difference that You Can See!

ConventionalPanoramic (OPG)

Imposition of Tissue

Projection Distortion

Cone Beam CT


157/180

NewTom PanoramicCone Beam CT

No Distortion

1:1 ScaleExact Measurements

j

Magnification Error

Working of a Cone Beam CT

Fan-beam of X-ray in CT Cone-beam of X-ray

Cone Beam CT


158/180

Working of a Cone Beam CT

Cone Beam CT


159/180

LA Feldkamp, LC Davis, JW Kress: Practical cone-beam algorithmJ. Opt. Soc. Am. (1984), 612-619


160/180

Panoramic ImagesRay Sum ImagesCone Beam CT


161/180

Unlimited post processing invariable slice thicknessMIP (Maximum Intensity Projection)

Cone Beam CT


162/180

Made by a Cone-Beam CT

Effective doseCone Beam CT


163/180

Illuma NewTomVG Ewoo Kavo/Icat NewTom Galileos

137 S 75 S 70 S 68 S 36 S 29 S

PlanmecaProMax 3DSirona GALILEOS

Cone Beam CT


164/180

2010

NewTom 3G NewTom VG

What to expect?

- CT in Cardiology




165/180

- CT in Archeology

- Cone Beam CT



- Radiation dose


- Dual Energy CT

- CT Techniques

Forensic Radiology


166/180

Forensic Radiology


167/180

Bicycle versus car; on purpose?

Shooting

- How many bullets?- Ballistic trajectory?

- Cause of death?

Forensic Radiology


168/180

?

Forensic Radiology Dental identification


169/180

UMCG

Exploded Bone Marrow

Dental identificationForensic Radiology


170/180

UMCGWe had a match!


171/180

Mummie Janus (RMO)

Meisje van Yde (Drents Museum)

Forensic Radiology


172/180

http://www.fbi.gov

Forensic Radiology


173/180

www.fbi.gov www.marylandmissing.com www.missingpersons.org

Meisje van NuldeForensic Radiology


174/180



175/180



176/180



177/180

RowenaRochelle

Forensic Radiology


178/180

Thanks to ultra sound specialist: Jan Visscher

Mouse !!!

Forensic Radiology


179/180

Last Dinner ???


180/180

Date post:	05-Apr-2018
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BMT 2012 Clinical CT Applications

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