LO1

Question 1

intrathecally route

Answer 1

into subarachnoid space around the spinal cord

Question 2

characteristics of positive contrast media

Answer 2

higher density, positive CT #

Question 3

examples of positive contrast media

Answer 3

iodinated solutions of IV and oral contrast, low density mixtures of barium

Question 4

characteristics of negative contrast

Answer 4

lower density, negative CT number

Question 5

examples of negative contrast

Answer 5

air, carbon dioxide

Question 6

characteristics of neutral contrast media

Answer 6

equal density to water (0 HU)

Question 7

examples of neutral contrast media

Answer 7

water, polyethylene glycol (PEG)

Question 8

what can be used with oral contrast to help speed up bowel motility

Answer 8

sorbitol

Question 9

when is intraarticular administration for CT arthrography done

Answer 9

when there needs to be simultaneous evaluation of the bone and soft tissue

Question 10

which phase comes first in intravenous contrast enhancement

Answer 10

arterial

Question 11

another name for the arterial phase

Answer 11

bolus phase

Question 12

another name for the venous phase

Answer 12

non-equilibrium phase

Question 13

another name for the delayed phase

Answer 13

equilibrium phase

Question 14

Arterial phase
- timing
- attenuation difference
- structures shown

Answer 14

20-30 seconds
30 HU between aorta & IVC
arterial structures shown

Question 15

venous phase
- timing
- attenuation difference
- structures shown

Answer 15

60-80 seconds
10-30 HU between aorta & IVC
arterial, venous, and organs shown

Question 16

delayed phase
- timing
- attenuation difference
- structures shown

Answer 16

3-5 minutes
- early = 3-5 mins
- late = 5-15 mins
no new contrast given
concentration equalizes (except kidneys)

Question 17

3 types of scan delay methods

Answer 17

bolus timing (test bolus)
bolus tracking (auto trigger)
fixed time delay

Question 18

bolus timing
- technique

Answer 18

small amount of contrast is given (10-20ml) with a mechanical injector. scans are performed at the same location and the time required for the peak opacification is recorded and used for the scan

Question 19

bolus tracking
- technique

Answer 19

full done of contrast is administered, several scans are done at the same location and once the ROI is fully opacified, the scan is initiated

Question 20

fixed time delay
- technique

Answer 20

patient is scanned at a predetermined time

Question 21

slow rate for venous and/or delayed scans

Answer 21

2-3ml/sec

Question 22

flow rate for CT angiography scans of arterial structures

Answer 22

5ml/sec

Question 23

don’t use contrast when…

Answer 23

studies looking for renal stones
CT scans looking for intracranial hemorrhage or hematoma (done w/o contrast first)