Teaching Cases II: CT Angiography Across the Ages - AAPM

Technology Assessment Institute: Summit on CT Dose

Teaching Cases II:

CT Angiography Across the Ages:

Single to 320 Slices

P. Rogalla, M.D.

Dept. of Medical Imaging

University of Toronto


Indication!


~ 35-40 mSv


~ 0.8 mSv


technical issues influencing scanning protocols

and radiation dose

difference b/w scanner generations

slice thickness, pitch, scanning times

consequences for contrast media injection

clinical examples


and radiation dose

CTA: outline




clinical examples



and radiation dose




clinical examples

CTA: outline


X-ray shutterX-ray shutter“over-ranging”

scanning area

additional rotation additional rotation


scanning area

additional rotation additional rotation

X-ray shutterX-ray shutter“over-ranging”


helical pitch >3

two tubes

wide area detector


wide area detector

16 cm16 cm

64-slice helical

additional rotation


512, 48 cm

51

2, 4

8 c

mpixel size:

0.94 mm

. . . . . . . . . . .

0.94

slice thickness:

1 mm


512, 48 cm

51

2, 4

8 c

m

0.94 mm

1 mm

. . . . . . . . . . .

0.94

1.0

slice thickness:

pixel size:

10 mm slices

5 mm slices

isotropic (1 mm)



and radiation dose




clinical examples

CTA: outline

spiral

z-axis

detector

4-slice CT

{{

25% 25%

spiral

z-axis

detector

4-slice CT

{{

10% 10%

spiral

z-axis

detector

16-slice CT

{{

5% 5%

64 x ~0.5 mm

32 x ~1.0 mm

spiral

z-axis

detector

64-slice CT


Bolus tracking:



and radiation dose




clinical examples

CTA: outline

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm

Collimation Pitch factor

Slice thickness, pitch

0.3 s 64-slice CT

0.5 s 4 -slice CT

13 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm


Slice thickness, pitch0.5 s 16-slice CT

8 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

5 s

40 cm

Scan time

0.5 s 16-slice CT


0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm125 s


0.3 s 64-slice CT0.5 s 16-slice CT0.5 s 4 -slice CT

40 cm

Scan time

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm




31 s

40 cm

Scan time

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

5 s

40 cm

Scan time

0.5 s 4 -slice CT0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm




100 s

40 cm

Scan time

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



25 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

4 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

83 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



21 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

71 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



18 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

63 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



16 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

56 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



14 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

50 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



13 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

63 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



16 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

5 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

50 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



13 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

4 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

42 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



10 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

36 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



9 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

31 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



8 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

28 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



7 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

25 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



6 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

31 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



8 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

5 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

25 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



6 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

4 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

21 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



5 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

18 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



4 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

16 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



4 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

14 s

40 cm

Scan time

0.5 s 16-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



3 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.5 mm

1.0 mm

2.0 mm

5.0 mm

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

13 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



3 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

13 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



8 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

5 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

10 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



6 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

4 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

8 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



5 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

7 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



4 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

3 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

6 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



4 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

6 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



3 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

2 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



0.3 s 64-slice CT

0.5 s 4 -slice CT

5 s

40 cm

Scan time

0.5 s 16-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm



3 s

40 cm

Scan time

0.5 s 4 -slice CT

0.3 s 64-slice CT

0.5 mm

1.0 mm

2.0 mm

5.0 mm

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0.8

1.0

1.2

1.4

1.6

1.8

2.0

3.0 mm

4.0 mm

8.0 mm

Collimation Pitch factor0.3 s 64-slice CT

0.5 s 4 -slice CTSlice thickness, pitch

2 s

40 cm

Scan time

0.5 s 16-slice CT

Scan duration, CM

Prokop, M. EJR 2000, 36: 86-96

Scan duration, CM

Bae KT, Heiken JP. In: Marincek B et al. Multislice CT 2000, 28-36

Injection speed, enhancement

http://www.ctisus.org/cta_web/12_04/12_04_Heiken/jpgs/Heiken_figure02.jpg

Source: Joachim Wildberger. Fleischmann D, Radiology 2005

0

50

100

150

200

250

300

0 20 40 60 80 100 120

time [s]

Rela

tive

En

ha

nc

em

en

t [

HU

]

2 ml / s

150 HU

Time frame: 32 s

32 s

20 40 60 80 100 120

time [s]

0

50

100

150

200

250

300

0R

ela

tive

En

ha

nc

em

en

t [H

U]

220 HU

16 s

Time frame: 16 s

4 ml / s

Injection speed, enhancement

Injection duration

Source: Joachim Wildberger 30s Injection

20s Injection

12s Injecton

8s Injection

5s Injection

3s Injection

1s Injection

0

50

100

150

200

250

300

350

0 5 10 15 20 25 30 35

Ao

rtic

En

ha

nce

me

nt (H

U)

time (after start of injection) (s)

0

50

100

150

200

250

300

350

0 5 10 15 20 25 30 35 40

Ao

rtic

En

ha

nce

me

nt (H

U)

time (after start of Injection) (s)

Saline chaser

Source: Joachim Wildberger

400

300

200

100

0 4020 8060

112 ml CM

112 ml CM

&

50 ml saline

4 cc / s



and radiation dose




clinical examples

CTA: outline


scanner: 4, 16, 64, 320?

tube settings, amount of contrast material?

newborn, partially corrected Fallot

suspected arterial and venous abnormalities

< 2 kg BW

scanner: 4, 16, 64, 320?

tube settings, amount of contrast material?


0

10

20

30

40

50

60

70

80

90

0 10 20 30 40 50 60

body weight [kg]

[mA

s]

0

10

20

30

40

50

60

0 10 20 30 40 50

body weight [kg]

[mA

s]

0

50

100

150

200

250

0 10 20 30 40 50

body weight [kg]

[mA

s]

Chest

Abdomen

Head

observed mAs settings

in paediatric CT


Exposure ~ Voltage 2.5

150 %

140 kV

100 %

120 kV

40 %

80 kV

Rel. Dose

Voltage

mAs x 2.5 at 80 kV

mA adaptation at 120 kV:

(body weight [kg] + 5) x f = mAs

f = 1 (chest), 1.5 (abdomen), 5 (head)

Exposure ~ Voltage 2.5

150 %

140 kV

100 %

120 kV

40 %

80 kV

Rel. Dose

Voltage

mAs x 2.5 at 80 kV


80 kV, 20 mAs, 0.5 mm, 1.5 ml CM


80 kV, 1.5 ml CM i.v.


120 kV, 1.5 ml KM i.v.

58 y/o man

ICU:

CTA, search for emboli

64-slice, 0.5 s rotation,

0.5 mm slices,

10 s acquisition time

Diagnoses:

pneumonia,

vascular calcifications,

left renal artery

occlusion

58 y/o man

ICU:

CTA, search for emboli

64-slice, 0.5 s rotation,

0.5 mm slices,

10 s acquisition time

Acute abdominal pain, known peripheral arteriosclerosis

chest pain triage

Hein PA et al. RöFo 2009

dynamic chest imaging + ventilation


isotropic scanning technique for CTA

caveat: thin slices with 4-slice CT scanners

arterial phase: bolus tracking

scanning time dependent on slice thickness,

pitch, scanner type – influences amount and

injection speed of CM

isotropic scanning technique for CTA

Summary

caveat: thin slices with 4-slice CT scanners

arterial phase: bolus tracking

scanning time dependent on slice thickness,

pitch, scanner type – influences amount and

injection speed of CM

Teaching Cases II: CT Angiography Across the Ages - AAPM

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Transcript of Teaching Cases II: CT Angiography Across the Ages - AAPM