ARRT Scan Protocols 3

Question 1

For a CT coronary angiography (CCTA) protocol, which heart rate range is generally ideal to minimize motion artifact?

Accepted Answer

<65 bpm

Answer

Heart rates below 65 bpm allow longer diastolic rest periods, reducing cardiac motion artifact during CCTA acquisition.

Question 2

When scanning for acute aortic dissection, the scan range should include:

Accepted Answer

Chest, abdomen, and pelvis

Answer

Aortic dissection can extend from the aortic root to the iliac arteries, so the entire aorta from chest through pelvis must be imaged.

Question 3

A CT myelography protocol requires which patient preparation step unique to this exam?

Accepted Answer

Intrathecal injection of iodinated contrast

Answer

CT myelography requires intrathecal (subarachnoid) injection of water-soluble iodinated contrast to opacify the spinal canal.

Question 4

Which pitch factor would result in the longest scan time for a given scan range?

Accepted Answer

0.5

Answer

A lower pitch means the table moves more slowly relative to rotation speed, resulting in more overlap and a longer scan time.

Question 5

In a CT urography (CTU) protocol, the excretory phase is typically acquired how long after IV contrast injection?

Accepted Answer

5–10 minutes

Answer

The excretory (nephrographic) phase of CTU is acquired 5–10 minutes post-injection to allow contrast to opacify and distend the collecting system and ureters.

(ARRT) American Registry of Radiologic Technologists Computed Tomography Certification Practice Test

(ARRT) American Registry of Radiologic Technologists Computed Tomography Certification Practice Test

ARRT Scan Protocols 3