GI Radiology

Question 1

General Approach

Answer 1

1) patient data, 2) study/image data
3) image quality & adequacy, 4) detection of any abnormality
5) describe abnormality, 6) differential diagnx, 7) assess for change

Question 2

Abd X-ray
also Hallmark of obstruction?
and Rule?

Answer 2

Usually supine
3-way abdomen series: PA CXR (most sensitive for free air), supine, and upright abd
HALLMARK OF OBSTRUCTION IS DILATION OF BOWEL
3,6,9 (normal cm caliber: small bowel, transverse colon, cecum)

Question 3

Fluroscopy (contrast contraindications)

Answer 3

No barium if upstream of colon obstruction
Avoid use of high osmolality (Gastrografin & Gastroview) in pts with proximal GI obstruction as aspiration can lead to Pulm Edema

Question 4

Fluroscopy (Barium Swallow/Esophagram)

Answer 4

Evaluates 3 phases of swallowing

Question 5

Fluroscopy (Upper GI)

Answer 5

Examines esophagus, stomach, duodenum

Question 6

Fluroscopy (Small bowel follow through SBFT)

Answer 6

Evaluation of jejunum, ileum, terminal ileum OFTEN COMBINED WITH UPPER GI
(takes a while)

Question 7

Fluroscopy (Enterolysis)

Answer 7

Gold standard of small bowel imaging BUT not as well tolerated, more costly, and higher radiation exposure than SBFT

Question 8

Fluroscopy (Barium Enema)

Answer 8

Evaluates colon and rectum
NOT immediately after endoscopic biopsy or in toxic megacolon due to danger of perforation (or if acute perforation suspected)

Question 9

Ultrasound

Answer 9

Used to evalute abd organs and biliary system

NOT for suspected appendicitis and specific peds

Question 10

Nuclear Medicine

Answer 10

spatial resolution inferior to other methods, can provide functional info not available otherwise

Question 11

CT

Answer 11

IV contrast improves eval of the bowel wall, solid organs, and vascular structures
BUT can mask abnormalities (eg. renal stones, subtle calcifications, hemorrhage)
SO VERY IMPORTANT TO PROVIDE HX and INFO ABOUT THE CLINICAL QUESTION

Question 12

CT (IV contrast risk)

Answer 12

Nephrotoxicity, allergic rxns, harm to fetus

Question 13

CT (indications for serum creatinine measurement BEFORE contrast)

Answer 13

> 60 yo, hx of renal dz, hx HTN, hx DM, use of Metformin drugs

Question 14

CT contrasts?

Answer 14

IV or enteric, enteric can be oral or rectal eg. water, barium, water-soluble

Question 15

MRI (IV contrasts? nephrotoxicity?)

Answer 15

gadolinium based - NO nephrotoxicity at MR doses, BUT risk of nephrogenic systemic fibrosis (NSF) in patients with renal dysfunctiokn

Question 16

Angiography/IR indications:

Answer 16

GI bleed, biliary obstruction, image-guided biopsy, abscess drainage, feeding tubes, portal hypertension,IR oncology