Radiology

Question 1

What is the best test for pneumoperitoneum?

Answer 1

CT is most sensitive, but can see on AXR

Question 2

What position should patient be placed in to identify air in the peritoneum on x-ray?

Answer 2

Left lateral decubitus or upright

Question 3

What is “thumbprinting” a sign of on abdominal x-ray?

Answer 3

bowel wall thickening

Question 4

What is appropriate imaging for possible Crohn’s dz?

Answer 4

CT with oral/IV contrast OR MRI

abdomen and pelvis

Question 5

List indications for oral contrast in CT

Answer 5

eval for IBD, abscess, extravasation after surgery, fistula mapping

Question 6

List indications for rectal contrast in CT

Answer 6

trauma to pelvis, distal colo-rectal abnormalities (fistula), suspicion for anastomotic leak

Question 7

List indications for IV contrast in CT

Answer 7

opacifies vasculature, viscera, urinary collecting systems - look for masses, abscesses, mesenteric ischemia, aneurysms

Question 8

Once IV contrast injected, how long should you wait to image if you want to highlight the arteries?

Answer 8

35-40 seconds

Question 9

Once IV contrast injected, how long should you wait to image if you want to highlight the solid abdominal viscera?

Answer 9

60-90 seconds

Question 10

Once IV contrast injected, how long should you wait to image if you want to highlight the renal collecting system?

Answer 10

5-15 min

Question 11

What is IV contrast material for MRI?

Answer 11

gadolinium

Question 12

Water is ___ Hounsfield units (HU).

Answer 12

0

everything else is compared

Question 13

What CT stage would you look for colon cancer liver metastases?

Answer 13

during portal venous phase - no arterial supply

Question 14

What can cause GB wall thickening?

Answer 14

hepatitis, hypoalbuminemia, ascites, pancreatitis, cholecystitis, adenomyomatosis, gallbladder cancer, AIDs

Question 15

What appendiceal wall thickness is seen in appendicitis?

Answer 15

diameter > 6 mm