Flashcards in CM-GI Radiology and Imaging Deck (64)
What is the difference between KUB, flat/upright abdominal series, and acute abdominal series?
KUB- patient is supine
flat/upright- supine and standing (bowel gas pattern and air fluid levels are better seen standing)
acute flat/upright/CXR (free air in the peritoneum which is seen easily under the right hemidiaphragm)
Describe how a normal colon would look on KUB.
1. bubbly apearance of fecal matter
2. peripheral location
3. widely spaced haustral markings
Describe the normal small bowel on KUB.
1. centrally located
2. smaller than 3cm in diameter
3. valvulae conniventes (folds) - usually seen with distention (go the whole way across, unlike colonic haustra)
What are the four common indications for KUB of the abdomen?
1. abdominal pain
2. suspected small bowel obstruction
3. suspected renal stones
4. suspected swallowed foreign body
(5. enteric tube positioning)
What are 4 classic KUB diagnoses?
1. pneumoperitoneum (acute)
2. mechanical small bowel obstruction (flat/upright)
3. paralytic ileus
4. abdominal calcifications
What is pneumoperitoneum a sign of? What imaging technique is best to see one? Describe what it would look like.
It is air in the peritoneal cavity and is a sign of bowel perforation.
The study of choice is acute abdominal series. (the CXR view is best for detection)
It is a dark area below the right hemidiaphragm
What do you do if a patient cannot tolerate an upright film when you suspect a perforated bowel?
Left lateral decubitus (patient lies on the left, right side is up)
The air in the peritoneum should rise to be above the liver
How does peritoneum show up on supine film?
air on both sides of the bowel wall = double wall sign
What imaging modality is used for suspected small bowel obstruction? Describe the appearance.
You would do flat/upright abdominal series.
You would see:
1. small bowel dilation (greater than 3cm)
2. paucity of colonic gas
3. air-fluid levels on upright film (can also be seen in paralytic ileus, gastroenteritis, normally)
What is the distinction between small bowel obstruction and paralytic ileus?
bowel sounds are reduced/absent in paralytic ileus
PI - small bowel and colon are slightly dilated and gas will be seem EVERYWHERE (small bowel, colon, rectum)
SBO - paucity of gas in the colon and more dilated small bowel
What imaging test is used to see abdominal calcifications?
In general, how can you tell the difference between a gallstone, kidney stone and pancreas?
KUB- but precise location of the stones is hard to ascertain
Gallstones tend to be in a clump and are faceted. They are always in the RUQ
Kidney stones can be on the left or right and are rarely faceted. Staghorn
Chronic calcified pancreatitis- small BB like calcifications outline the whole course of the pancreas (CT would be test of choice for pancreas though)
Describe the process of barium swallow. When is using barium sulfate contraindicated?
What can be used in its place?
A patient swallows barium and while the contrast is being given the radiologist takes focused X-rays of the GI tract, specifically from cervical esophagus to the GE junction
Barium is contraindicated if bowel perforation is suspected because it can lead to barium pertonitis.
Gastrografin - don't use if they could aspirate (lung edema)
What are the 5 types of GI contrast studies?
1. Barium Swallow
2. Upper GI Series (UGI)
3. Small Bowel Follow Through (SBFT)
4. Barium Enema
What are the 3 most common indications for a barium swallow?
1. Dysphagia (trouble swallowing)
2. chest pain (non-cardiac)
What are 4 common diagnoses made by barium swallow?
1. Esophageal carcinoma
3. Hiatal hernia
What test is done for esophageal carcinoma? What would it look like?
Endoscopy has largely replaced it, but barium swallow.
You would see strictures, sharp overhanging edges, irregular mass with ulcerations.
Benign tumors tend to be smoother
What test is done for esophagitis?
Barium swallow- multiple irregular mucosal ulcerations
What is a hiatal hernia and what test is used to diagnose hiatal hernias?
It is when part of the stomach herniates through the esophageal hiatus into the thorax.
It can be seen on barium swallows AND UGI. The stomach rugal folds are seen above the diaphragm
What is achalasia and what test is used to diagnose?
It is an esophageal motility disorder where the LES is dysfunctional
You do a barium swallow. You will see a massive dilation of the esophagus with smooth narrow sphincter
What are four common indications for a UGI series?
1. abdominal pain
2. suspected gastric or duodenal ulcer
3. suspected hiatal hernia
4. suspected gastric mass
What are the two types of UGI series? When would you use each?
1. Double-contrast where the patient swallows barium and then an effervescent tablet to distend the GI tract with air. This allows better eval of fine mucousa detail (small masses, ulcerations)
2. Single-contrast- used when the patient cannot tolerate effervescent granules, positioning for the UGI or you are only checking for a bowel perforation
What test is used for duodenal ulcers? what does it look like?
UGI series and it has:
1. persistent contrast collection
2. smooth mound surrounding edema
3. thickened folds radiating to ulcer crate
What test is done for gastric ulcers? What do you see for benign? Malignant?
Benign- smooth mounds of edema surrounding the ulcer, persistent contrast collection, smooth craters
Malignant- irregular ulcer crater, irregular mass around crater, irregular folds
Describe the process of SBFT.
Patient drinks barium solution and overhead KUBs are done to evaluate contrast passing through the small bowel. Also fluoroscopy can be done to "watch it live'
What are 5 indications for small bowel follow through?
1. obstruction (intermittent or partial)
3. chronic GI bleed w/o source
4. malabsorption syndromes and diarrhea
5. IBD (Crohn's)
What test is used to diagnose Crohn's disease? What does it look like?
Crohn's is diagnosed with SBFT because it most often affects the terminal ileum. You see:
1. thickened, nodular folds
3. "cobblestone" mucousa
4. fistulae to other organs
5. Skip areas
What are the six common indications for barium enema?
1. chronic Gi bleed -hemoccult + stool
2. large bowel obstruction
3. left lower quadrant pain
What are the 2 types of barium enema and when is each used?
1. Double contrast- barium and air contrast
2. single contrast- just barium. only used when rapid gross information is needed (large bowel obstruction, colonic leak/perforation, diverticulosis)
What test is done to look for colonic carcinoma? How would it look?
It is a polyploid mass with irregular strictures. It looks like an apple core (irregular lumen narrowing with sharp overhanging edges