8. Vasdev - GI Imaging (P900/CB)
Terms in this set (62)
What are the three choice of imaging studies for an upper GI tract issue?
1) Upper endoscopy
2) UGI study (limited for findings ulcers and erosive gastritis)
3) Barium swallow
What are the three choice of imaging studies for a small bowel issue?
1) CT with contrast (IV and oral)
2) CAPSULE endoscopy
3) Small bowel follow-through (SBFT)
What are the two choice of imaging studies for colon issues?
What is the choice of imaging for gallbladder issues?
2) Barium ENEMA
The most common plain film of the abdomen is an _______ view with the patient in the (supine/prone) position
Plain radiographs of the abdomen are also called a ____
ANTEROPOSTERIOR veiw with the patient in SUPINE position
If a patient comes in with severe acute abdominal pain, what kind of plain films would you get?
- PA chest
- UPRIGHT abdominal film
TRUE or FALSE: A gastric air bubble seen on plain film is abnormal
FALSE! There is almost always air in the stomach!
- Also, there normally should be small amounts of air in the small and large bowel
HY/TEST: List two clues that allow you to tell a small bowel on plain film
1) CENTRALLY placed
2) Plicae circulares (VALVULAE CONNIVENTES) markings extend all the way across the lumen and are closer together
HY/TEST: List two clues that allow you to tell a large bowel on plain firm
1) PERIPHERALLY placed
2) HAUSTRA markings DO NOT extend completely across, and are usually WIDELY spaced apart
What are random calcifications in veins called (that can be seen on plain film)?
Why do we do luminal contrast studies, such as a barium swallow? What other contrast agent is used, specifically in pt with obstructive dz?
What are the three main points of restriction/constriction in barium swallow studies?
To visualize the lumen and possibly to view the organ in motion (fluroscopy)
Water can also be used to visualize.
1) aortic arch
2) Left main bronchus
3) Left atrium
Nowadays, the most common imaging choice of the upper GI tract is what?
What is a modified barium swallow imaging study?
- The contrast in this modified version will appear ______ instead of ______
What is the goal?
Video fluoroscopic swallowing evaluation (VFSE)
- The contrast will appear BLACK instead of WHITE
Assess swallowing for safety issues related to aspiration and dietary requirements
Lower GI X-rays, also known as a ______ ______, examines the _____ to the _______.
Lower GI x-rays, also known as a BARIUM ENEMA, examines the COLON to the RECTUM
What is an absolute contraindication for doing any barium study on the GI tract?
If there is a risk for PERFORATION
- Extreme abdominal pain
- Recent biopsy
One major disadvantage of barium studies (plain films, UGI or LGI) is it does not have the ability to ______ if necessary
- Must follow up with a scope to get some tissue out
TRUE or FALSE: CT scans have a relatively moderate/high amount of radiation
TRUE (always a risk)
When is an abdominal MRI most commonly used as the imaging study of choice? (in what situation is MRI better)
What is the biggest advantage to getting an MRI (vs plain film or CT scan)?
When you want to differentiate ABNORMAL (diseased) tissue from normal tissue
It does NOT involve ionizing radiation!
What is a rare, but serious complication of MRI with contrast?
Nephrogenic systemic fibrosis
-injection of high doses of gadolinium-based contrast material
HY/TEST: In terms of the GI tract, list three situations which ultrasound can be extremely helpful in. What procedure is ultrasound commonly used for?
1) Enlarged organs
Needle aspiration biopsies!
(Fluid/bone/gas) can interrupt the images from an ultrasound
GAS (or air)
What are two other imaging modalities that are used especially to evaluate the hepatobiliary and pancreatic duct systems?
1) Endoscopic retrograde cholangiopancreatography (ERCP)
2) Magnetic resonance cholangiopancreatography (MRCP)
What does a transjugular intrahepatic portosystemic shunt (TIPS) do? When would you get a TIPS procedure done?
It CREATES a pathway (SHUNT) through the liver that connects the portal vein to one of the hepatic veins
- Used if the liver is cirrhosed and their is major backup of the portal vein
_____ scan is one common example of nuclear imaging, and is usually done after an ______ of the ______
- 99m Tc-hepatic iminodiacetic acid scan
Usually done after an ULTRASOUND of the GALLBLADDER to assess for gallstones
Small bowel obstructions are caused by excessive ____ or _______ loops, usually from _______.
On the other hand, a functional ileus is a more _____ distension and is usually caused _______
Small bowel obstructions are caused by excessive GAS (air/fluid levels) or DISTENDED loops, usually from ADHESIONS (can be from hernias, neoplasms)
On the other hand, a functional ileus is a more DIFFUSE distension and is usually caused POSTOPERATIVE
Air/fluid levels are not a problem in what two areas of the GI tract? Where are they a problem?
STOMACH and LARGE bowel
- Air/fluid levels in the small bowel is a problem
If you know a patient is postoperative and presents with fever, chills, and abdominal pain, what do you expect to see on plain film?
FUNCTIONAL ILEUS (diffuse distensions)
Air/fluid levels in the small bowel is a classic example of obstruction and has a characteristic ______ sign on plainfilm
TEST: A "coffee bean" sign on plain film on the large colon usually points to what pathology?
- Much more common than CECAL volvulus
What is pneumoperitoneum? Are all causes pathological?
Gas within the peritoneal cavity of the abdomen that has escaped from the bowel lumen
A number of causes are not harmful and are to be expected, for example following laparotomy or laparoscopy
TEST/TRUE or FALSE: An air bubble on the R side (where the gastric bubble would be on the L side) is normal
FALSE, that is FREE AIR in the peritoneum
80% of kidney stones and 20% of gallstones are radio______
- This means more times if you see an opacity around the kidney/gallbladder area, it will most likely be a KIDNEY STONE
What is achalasia?
What is it's key findings on radiography?
Aperistalsis (failure of the smooth muscle fibers to relax, which can cause the sphincter to remain closed)
- Most commonly associated with the esophagus
BIRD'S BEAK sign
TEST: An "apple core" lesion on the large colon is a classical sign of what?
Ischemic colitis classically has a ______ sign on plain film of the colon
RECALL: Feathery features of the small intestine usually point to what part of the small bowels?
What is gas producing in the gallbladder called?
A 53-year old male presents to the ER with nausea and vomiting and acute onset of epigastric abdominal pain radiating to the back. He said he doesn't drink any alcohol. Lab results reveal an elevated serum amylase and lipase. This is his first time he has had these symptoms. Which of the following is the ACR recommended imaging modality for this patient?
A) RUQ ultrasound
B) RLQ ultrasound
C) CT scan of abdomen w/ contrast
D) MRI of abdomen
E) Abdominal plain films
A) RUQ ultrasound
The symptoms of pain radiating to the back with acute onset nausea and vomiting, along with elevated serum amylase and lipase, points to pancreatitis. Two most common causes of this are alcohol and GALLSTONES, so in this case, the patient has gallstone pancreatitis. Therefore, the gold standard for seeing gallstones is an ULTRASOUND!
Calcifications in the pancreas are associated with (acute/chronic) pancreatitis
MEGA HY: Distinguish between large and small bowel characteristics, namely:
2) Name of folds
4) Common obstruction etiologies
A) Small Bowel:
-2.5 cm - 3 cm diameter
- adhesion/hernia/tumor/gall stones
B) Large Bowel
What are the susceptible watershed regions in the abdomen? How does CT Angiogram help us evaluate them?
1) ileal-cecal transition
2) splenic flexure
3) recto-sigmoid junction
CT Angiogram -> directly examines vessels
What are key features of benign gastric ulcers with regards to imaging?
At least two of the following:
2) smooth lucent line (Hampton line) or collar at the neck of the ulcer
3) normal rugal folds that radiate to the edge of the ulcer collection
4) complete and permanent healing of the ulcer on repeat study
What are key features of Crohn's Dz on CT?
1) Small bowel involvement
2) Wall thickening
3) Segmental narrowing
What is Meckel's Diverticulum and what are are the key features on radiograph?
Persistent remnant of the omphalomesenteric duct presenting with:
1) Congenital abnormality
2) Distal ileum
3) Painless rectal bleeding
Radiology has improved so much with time, let's kick it into active learning mode! (switch to definition first)
Even Pluto looks better these days! (gif is of images of Pluto from a space mission)
Ascending colon (a)
Descending colon (b)
Identify points a-d
Soft tissue (c)
Identify tissue types of a-d
c) Right/left kidney
d) Psoas muscle
f) Ascending colon
g) Descending colon
i) Small intestine
Identify points a-i
-caused by stricture @ GE junction
Barium swallow study reveals etiology of a patient with dysphagia, what is seen here? What is the pathophysiology?
Achalasia "bird's beak" - tapered narrowing, esophageal aperistalsis and dilatation. beaklike appearance
Case: 30 yo with dysphagia and regurgitation of undigested food. Dx?
Squamous cell cancer (apple core like lesion)
Case: 65 yo with weight loss, dysphagia and odynophagia.
Case: 35 yo with GERD and recent dysphagia.
KEY: Reflux is causing the problem!!!!
Left: Small bowel obstruction with extensive dilation
Right: air/fluid levels in multiple locations
Dx: Sm. Bowel Obstruction!
Pt presents with abdominal pain, what is going on in the radiographs? Dx?
Coffee bean -> sigmoid volvulus
Coffee been sign, midabdomen and pelvis
Pt presents with constipation, abdominal distension, and has EXTREME tenderness to palpation. Radiograph is attached, dx?
a.CT scan of abd/pelvis WITH contrast.
Patient has small bowel obstruction!
Case: A 24-year-old male presents to urgent care with abdominal pain, nausea, and vomiting. Which of the following is the ACR recommended imaging modality for this patient?
a. CT scan of abdomen and pelvis with contrast
b. CT scan of abdomen and pelvis without contrast
c. MRI of abdomen and pelvis
d. Ultrasound of abdomen and pelvis
e. UGI with small bowel follow-through
c. Mechanical obstruction of small bowel (surgical adhesion?)
Case: A 65-year-old woman presents with abdominal distention and a history of abdominal surgery. This patient most likely presents with?
a. Functional ileus
b. Gastric outlet obstruction
c. Mechanical obstruction
d. small bowel
A! Functional ileus of bowel - dilated bowel, distention, extending to rectum without signs of obvious mechanical obstruction.
Case: A 66-year-old man presents with fever, chills, and abdominal pain. This patient most likely presents with?
a) Functional ileus of bowel
b) Mechanical obstruction of colon
c) Mechanical obstruction of small bowel
Case: An 80-year-old man presents with
abdominal distention. What is present on abd xray?
Some sort of annular carcinoma
Case: 74-year-old man presents with severe diarrhea with some bleeding after being treated for a febrile urinary tract infection. Dx?
-dilated biliary ducts
-thickened duct walls
Pt presents with Charcot's triad, CT is performed and attached, what is your dx? Broadly characterize pathophysiology.
-confirm with HIDA
Case: 36-year-old woman presents with flank pain.
Ultrasound is performed, dx? What is a confirmatory test?
Dx: Nephrolithiasis - much more likely to be detected on xray than gallstones, due to radiopaque quality. Kidney stones can also present with abdominal pain.
Case: A 64-year-old man presents with hematuria. CT is performed. What is your dx?
Appendicolith (or fecolith)
trapped in ascending colon
Pt presents with abdominal pain. Describe location of radiopacitiy and describe etiology.