Gastrointestinal: Luminal, Stomach Flashcards
Think malignant ulcerated stomach cancer
Note: This is the Carmen Meniscus sign.
Think benign gastric ulcer
Note: There is a Hampton’s line (red arrows).
Gastric ulcer that is wider than it is deep, with nodular edges, and gastric folds adjacent to the ulcer…
Think malignant ulcerated cancer
Note: Look for Carmen Meniscus sign (highly suggestive of cancer).
Gastric ulcer that is deeper than it is wide, with sharp contour, and gastric folds radiating to the ulcer…
Think benign gastric ulcer
Note: Look for Hampton’s line (highly suggestive of benign ulceration).
What is the most common mesenchymal tumor of the GI tract?
Gastrointestinal stromal tumor (GIST)
What is the most common location for GIST?
Stomach (70%)
Note: Duodenum is the second most common.
What age group do GISTs occur in?
Older pts (rare before age 40)
Gastrointestinal stromal tumors are associated with…
- NF1
- Carney’s triad
Is lymphadenopathy common in GIST?
No
Where is the most common location for GIST metastases?
Liver
Note: Metastases are very uncommon (which is why lymphadenopathy is uncommon).
Carney’s triad
- Pulmonary chondroma
- Extra adrenal pheochromocytoma
- GIST
What is the most common gastric malignancy?
Adenocarcinoma (followed by lymphoma)
Note: Malignant GIST is very rare.
Risk factors for gastric adenocarcinoma
- H. pylori infection
- Older age
- Pernicious anemia
- Menetrier’s disease
- Prior gastroenterostomy (old treatment for peptic ulcer disease)
Metastatic spread of gastric adenocarcinoma to the ovary…
Krukenberg tumor
Gastric adenocarcinoma with a left supraclavicular mass…
Think metastatic spread to a left supraclavicular lymph node (Virchow node)
Appearance of GIST vs gastric adenocarcinoma on imaging
GIST is usually smoothly marginated and exophytic
Gastric adenocarcinoma is usually large, ulcerated, and heterogeneous asymmetric wall thickening
What are the major types of gastric lymphoma?
- Primary (MALT)
- Secondary (systemic lymphoma)
What is the most common extra nodal site for non-Hodgkin lymphoma?
The stomach
Which gastric cancer is most likely to cause a gastric outlet obstruction?
Adenocarcinoma (if in the gastric antrum)
Note: Lymphoma rarely causes gastric outlet obstruction.
Major complication of chemotherapy treatment for gastric lymphoma
Gastric perforation
Classic imaging appearance of gastric lymphoma
Diffuse gastric wall thickening (>1 cm) without gastric outlet obstruction
Note: It often crosses the pylorus.
Stomach metastases are most likely to be from what primaries?
- Melanoma
- Breast
- Lung
Note: Gastric metastases are very rare.
Linitis plastica
Diffuse infiltration of the gastric wall, creating a contracted stiffened appearance
Note: This is usually due to breast/lung metastases or gastric lymphoma.
Diffuse thickening of the gastric wall, suggestive of linitis plastica (think breast/lung mets or gastric lymphoma)
Multiple gastric ulcers with no duodenal ulcers…
Think chronic aspirin therapy
Note: Aspirin does not cause duodenal ulcers.
Multiple duodenal ulcers…
Think Zollinger-Ellison syndrome
Note: Most duodenal ulcers are solitary.
What is this gastric mucosal pattern called?
Areae gastricae (normal finding)
When does the normal areae gastricae mucosal pattern become enlarged?
- Elderly pts
- H. pylori infection
- Focally enlarged next to an ulcer
Double contrast upper GI demonstrates absent areae gastricae…
Think atrophic gastritis
Menetrier’s disease
Idiopathic gastropathy with regular regal thickening at the fundus (sparing the antrum)
Complication of Menetrier’s disease
Hypoalbuminemia
Gastric regal thickening in the fungus that spares the antrum…
Think Menetrier’s disease (an idiopathic gastropathy)
Ram’s horn deformity (tapering of the gastric antrum, often seen in Crohns disease and other conditions)
Differential for Ram’s Horn deformity (tubular tapering of the gastric antrum)
- Scarring from peptic ulcers
- Granulomatous disease (e.g. Crohns, sarcoid, tuberculosis, syphilis)
- Scirrhous carcinoma
What is the most common gastrointestinal location for sarcoidosis
Stomach
What are the two major types of gastric volvulus?
- Organoaxial (gastric antrum stays below the GE junction)
- Mesenteroaxial (gastric antrum ends up above the GE junction)
Which type of gastric volvulus is more common?
Organoaxial (gastric antrum remains below the GE junction)
Which gastric volulus is more problematic and needs to be corrected?
Mesenteroaxial (gastric antrum ends up above the GE junction)
Which type of gastric volvulus is more common in kids?
Mesenteroaxial (the problematic one that can cause obstruction/ischemia and needs to be fixed)
Soft tissue mass posterior to the gastric fungus that appears to communicate with the gastric lumen…
Think gastric diverticulum
Note: This can easily be confused with an adrenal mass.
Isolated gastric varices…
Think splenic vein thrombosis (e.g. pancreatitis or pancreatic cancer)
Common complications of gastric banding
- Stomal stenosis (most common)
- Gastric band erosion
- Band slippage
Vomiting s/p gastric banding with upper GI demonstrating a dilated proximal gastric pouch…
Stomal stenosis (band is too tight)
Note: This is the most common complication of gastric banding.
CT demonstrates that a gastric band is within the gastric lumen…
Gastric band erosion
Gastric band slippage
Note: The gastric band should be oriented in the 2:00 position relative to the spine. If it is more horizontal than this, think slippage.
What is the correct position for a gastric band?
- 2:00 position relative to the spine
- Phi angle between 5 and 60 degrees (angle between the spine and band)
Billroth 1 procedure
Resection of the gastric pylorus with anastomosis of the proximal stomach to the duodenum
Billroth 2 procedure
Partial gastrectomy with anastomosis of the proximal stomach to the jejunum
Common indications for Billroth procedures
- Gastric cancer
- Gastric ulcers
- Pyloric dysfunction (Billroth 1)
Which is associated with more complications: Billroth 1 or Billroth 2?
Billroth 1 tends to more early postoperative complications (but less gastritis) than Billroth 2
What are the 2 small bowel limbs created by a Billroth 2 procedure?
- Afferent bilio-pancreatic limb
- Efferent gastrojejunal “feeding” limb
Complications of Billroth 2 procedure
- Dumping syndrome
- Afferent loop syndrome
- Gastric cancer (increased risk 10-20 years after surgery)
Roux-en-Y gastric bypass
Stomach is divided to create a small gastric pouch which attached to the jejunum. A jejunojejunal anastomosis is also created to connect the afferent limb to the efferent limb.
Note: The excluded stomach attaches and drains to the duodenum as normal.
Afferent loop syndrome
Obstruction of the afferent loop (in Billroth 2, roux-en-Y, etc.) leading to an accumulation of secretions, bile, and pancreatic juice in the afferent limb. This can lead to bile duct dilatation and pancreatitis.
What causes afferent loop syndrome?
Obstruction of the afferent loop:
- Extrinsic causes (adhesions, internal hernia, neoplasm)
- Intrinsic causes (radiation scarring, edema from a marginal ulcer)
Which procedures may be complicated by afferent loop syndrome
- Billroth 2
- Roux-en-Y
- Whipple
- Partial pancreaticoduodenectomy
Bilious vomiting with a remote history of a Billroth 2 procedure
Afferent loop syndrome (due to obstruction of the afferent loop)
Postprandial diarrhea, nausea, and lightheadedness with history of recent Roux-en-Y gastric bypass…
Think dumping syndrome (due to rapid gastric emptying)
Treatment for dumping syndrome secondary to Billroth 2 procedure
Conversion of Billroth 2 to Roux-en-Y gastric bypass
Note: Roux-en-Y also gets dumping syndrome, but usually only in the early postoperative period.
Gastric fold thickening and filling defects seen in the stomach after a Billroth 1 or Billroth 2 procedure…
Think bile reflux gastritis
Jejunogastric intussusception
A rare complication of gastro-jejunal anastomosis where the jejunum herniates into the stomach
Note: This can cause gastric obstruction.
When do leaks tend to occur following bariatric surgeries?
Early postoperative (within 10 days)
Upper GI series demonstrated a gastric bypass with contrast moving from the gastric pouch to the gastric remnant…
Gastro-gastric fistula
Marginal ulcers
Peptic ulcers at or near a gastrojejunal anastomosis
What is the most common location for a marginal ulcer?
Just distal to a gastrojejunal anastomosis (the small bowel is not used to stomach acid)
Multiple giant marginal ulcers just distal to a gastrojejunal anastomosis…
Think chronic jejunal ischemia
What are the three main places a small bowel obstruction could happen after Roux-en-Y gastric bypass?
- Obstruction of the alimentary “roux” limb
- Obstruction of the biliopancreatic limb (closed loop obstruction)
- Obstruction below the jejunojejunal anastomosis
Why is a small bowel obstruction of the biliopancreatic limb particularly dangerous?
This is automatically a closed loop obstruction (because the excluded gastric remnant is sewed shut)
Small bowel obstruction s/p Roux-en-Y gastric bypass with dilatation of the gastric pouch and jejunal roux limb, but the biliopancreatic limb and excluded stomach remain decompressed…
Think obstruction of the alimentary “Roux” limb
Note: This is best seen on upper GI series.
What are the two major types of Roux-en-Y gastric bypass?
- Ante-colic (Roux limb passes anterior to the transverse colon)
- Retro-colic (Roux limb passes posterior to the transverse colon)
Note: To create the retro-colic gastric bypass, the surgeon needs to create a small defect in the transverse mesocolon, which increases the risk of internal hernias later on.
What are the major sites of internal hernia following Roux-en-Y gastric bypass?
- Defect in the transverse mesocolon (for retro-colic gastric bypasses)
- Mesenteric defect at the jejunojejunal anastomosis
- Herniation behind the roux limb mesentery
