GI Radiology Flashcards
(24 cards)
Zenker’s diverticulum occurs at?
A weakened area at the back of the throat known as Killian’s triangle. It is superior to the cricopharyngeus m. and inferior to the thyropharyngeus m.
It is a false diverticulum.
Symptoms of ZD
Trouble swallowing, halitosis, cough.
How is ZD diagnosed?
Fluoroscopic barium esophagography.
What is the risk of performing an endoscopy in a patient w/ ZD?
The scope may protrude through the diverticulum.
What test is best for hiatal hernia?
XR Barium
Lead-pipe sign
Suggests long-standing ulcerative colitis due to the loss of haustral markings.
XR Barium enema
Used to identify abnormalities of the large intestine (i.e. polyps or inflammatory bowel disease).
How to test for achalasia?
Barium swallow.
Achalasia pathology
Failure of the LES to relax.
Chargas disease
Achalasia from an infection.
What is the modality of choice for visualization of the biliary tree?
ERCP
What’s unique about ERCP?
It can be used as both a diagnostic tool as well as for treatment for gallstone stone obstructions and stenting.
How is ERCP performed?
A tube is passed into the 2nd portion of the duodenum and contrast is injected into the Ampulla of Vater. Then an XR is done for visualization.
What is the risk associated with ERCP?
5-10% risk of iatrogenic (physician induced) pancreatitis.
What does digital subtraction angiography help to identify?
Compromised arterial flow
How is digital subtraction angiography performed?
Catheter is inserted and dye is injected to provide contrast to visualize arterial supply to a specific region.
What is the choice diagnostic for cholelithiasis in the US?
Ultrasound, because only about 20% of gallstones are noticed on XR.
Symptoms of cholelithiasis
RUQ pain that can radiate to shoulder.
Positive Murphy’s sign.
CT facts
Quick Lots of radiation Good look at solid organs and fat. Good for calcification (stones) Good for overall look at pelvic structures, but with little detail.
MRI facts
Longer
Less radiation
Best to visualize tissues.
Excellent for pelvic organs
5 steps to visualization of images
- Solid organs
- Gb/biliary tree
- LN chains
- Somach, duodenum, SI, LI
- Fat planes, abdominal wall, bones
Retroperitoneal organs
Suprarenal gland Aorta/IVC Duodenum (2-4 parts) Pancreas Ureters Colon (ascending and descending) Kidneys Esophagus Rectum
SMa. syndrome
3rd part of duodenum is compressed between SMa. and aorta.
Can be caused by rapid weight loss, short ligament of Treitz, or anything else that can narrow the angle between SMa. and aorta.
Nutcracker syndrome
Left renal v. compressed between SMa. and aorta.
