GI Radiology

Question 1

Manometry does what?

Answer 1

how the muscular esophagus works

catheter in the esophagus and measure the strength of contractions. good for achalasia or GERD, but manometry isn’t good for anatomic in nature.

Question 2

X-rays

Why use it?

Who needs to be cautious?

What are the special cases? (5)

Answer 2

super cheap compared to a CT.

low level of radiation –> precaution for pregnant patients (typically you get a pregnancy test before getting an Xray) or use a metal apron.

Fluoroscopic barium esophagography (barium swallow)

barium enema

ERCP (catheter of area, put in contrast, and X-ray it)

digital subtraction angiography

KUB (kidney, ureter, bladder). for kidney stones, gallstones, blocks, but it should be done alongside other modalities because it’s not amazing.

Question 3

Zenker’s Diverticulum –> what is it, what is it caused by, where can you find it usually?

Answer 3

false diverticulum, but doesn’t contain the muscular Layer which is why it’s false

cause is uncoordinated swallowing and the cricopharyngeal muscle fails to relax.

Occurs in Killian’s Triangle (weak area right above the cricopharyngeus M. and inferior to the thyropharyngeus m. where the outpouching can occur)

Question 4

Zenker’s Diverticulum –> What are the symptoms?

how is it diagnosed?

caveat?

Answer 4

difficulty swallowing, persistent halitosis (terrible breath that won’t go away), cough

rarely a mass is found but it could be if it was really bad.

barium swallow (fluoroscopic barium esophagography)

DO NOT form an endoscopy because if you stick an endoscope in you can cause a rupture and you’re screwed

Question 5

Hiatal Hernias

2 types?

what do you see on each one and with pressures?

what part of the stomach herniates in each?

which one presents with reflux?

Answer 5

abdominal structures herniating into the thoracic cavity.

Paraesophageal vs. sliding.

sliding hiatial hernias = hourglass + GEJ is elevated + cardia displaced – reflux prone

para = GEJ unaffected, fundus is displaced

Question 6

Barium enema? what are we looking for?

Answer 6

“lead pipe sign”

long standing ulcerative colitis loses up the haustra, the colon looks like a lead pipe

Question 7

Achalasia and the barium swallow?

Answer 7

LES can’t relax.

you’ll see a “bird beak” sign.

the person presents with difficulty swallowing for liquids and solids.

Question 8

ERCP? what does it look at?

what is it the main modality for?

how does it work?

what is it good for diagnosing?

Answer 8

Endoscopic retrograde Cholangiopancreatography.. you’re looking at gall bladder, biliary tree, main pancreatic duct, and accessory stuff.

main modality for visualization of the biliary tree!

you take a tube and pass it to the 2nd portion of the duodenum and contrast is injected into the ampulla of vater.

typically used for diagnosing a gallstone obstruction.

Question 9

What is digital subtraction angiography?

Answer 9

catheter, contrast, take an X-ray.

it’s good for compromised arterial flow (obstruction because if you don’t see contrast going to where it should something’s blocking it.

Question 10

Ultrasonography is the main procedure of choice when diagnosing what?

Answer 10

cholelithiasis (gallstones).. because Xray only picks up about 20% of them.

use high frequency sounds to produce images of internal structures.

Question 11

CT vs. MRI

time?

radiation?

what kinds of people can’t do them?

what is CT and MRI good for?

Which is good for looking at Calcification?

Iodine or Gadolinium based?

Answer 11

CT is a lot faster than an MRI.

CT uses radiation which is bad. MRI does not have radiation.

MRI uses magnets, so no one with metal can have them done.

CT is good for solid organs, best spatial resolution, MRI is good for tissue resolution.

CT is better for calcification

CT = Iodine

Question 12

Interpretation of images steps? 5 steps

Answer 12

1. solid organs come first -> liver, spleen, pancreas, kidney, adrenal glands
2. Gallbladder/biliary tree
3. lymph node chains
4. duodenum before stomach, rest of small bowel, colon
5. fat planes, abdominal wall, bones

Question 13

What are the vertebral associations for the SMA, duodenum, and pancreas?

Answer 13

SMA at T12/L1 region, 1st part of the duodenum at L1.

L2 and L3 for 2nd part and the head of the pancreas

Question 14

SADPUCKER again?

Answer 14

retroperitoneal structures

Suprarenal gland
Aorta/IVC
Duodenum (2-4)
Pancreas (except tail)
Ureters
Colon (asc,des)
Kidneys
Esophagus
Rectum

Question 15

T10 is what portion of the stomach?

Answer 15

gastroesophageal junction

Question 16

What’s important to know about a sagittal plane CT and the pathologies that we see?

Answer 16

you can look for superior mesenteric artery syndrome.

portion of the duodenum is compressed (small bowel obstruction) between the SMA and the aorta caused by rapid weight loss!! it narrows the angle between the SMA and aorta.

also nutcracker syndrome, left Renal vein compressed between SMA and aorta