Radiology GI tract

Question 1

what is fluoroscopy?

Answer 1

radiographic movie (exposure)
Active examination
Structural AND functional information
Outlining of lumen – structure
Progression of contrast – function

Question 2

list the 3 contrast agents

Answer 2

1) Air
2) Barium
3) Iodinated water-solube (Gastrografin® and Gastroview)

Question 3

what contrast agent is the better choice to evaluate luminal obstruction in the GI tract

Answer 3

Barium

Question 4

how could a barium swallow cause peritonitis

Answer 4

If upstream of a mechanical colon obstruction

Question 5

when is an iodinated water-soluble agent indicated

Answer 5

possible gut perforation

Question 6

why should a iodinated water-solube agent be avoided in a proximal GI obstruction?

Answer 6

aspiration can lead to pulmonary edema

Question 7

what is double contrast?

Answer 7

Use barium to coat, air (pumped or pills) to distend

Better mucosal detail

Question 8

what is Small Bowel Follow Through (SBFT)

Answer 8

Often done in conjunction with upper GI

Do “compression” fluoroscopic views of areas of concern

Question 9

what are some pathologies that can be elucidated with Small Bowel Follow Through (SBFT)

Answer 9

Crohn disease, 
lymphoma, 
tuberculosis (TB), 
sprue, 
adhesions, 
partial/intermittent obstruction

Question 10

what are the Types and indications of barium enemas

Answer 10

Double contrast: rectal bleeding, polyps, cancer, IBD
Single contrast: fistula or sinus tract, patient unable to tolerate or cooperate with double contrast study
Water soluble contrast (Gastrografin®, Gastroview): risk for intestinal perforation, therapeutic for disimpaction

Question 11

what are the Contraindications to any type of barium enema

Answer 11

Suspected acute perforation
Acute, fulminating colitis (toxic megacolon)
Immediately after biopsy

Question 12

what are common indications for US

Answer 12

Gallbladder (cholecystitis) and biliary system.
Solid organ lesions; can also help differentiate between solid vs. cystic.
Appendicitis (esp. in children and pregnant women)
Vascular flow evaluation (Doppler)

Question 13

hepatocellular carcinoma is best detected during which phase of CT scan

Answer 13

arterial (hepatocytes receive most of their perfusion from hepatic artery)

Question 14

what is the ARC rating scale and what do they mean?

Answer 14

evidence based guidelines for the appropriate use of imaging studies. Ratings are:
1-3 = test is not appropriate
4-6 = may be appropriate
7-9 = usually appropriate