Gi -- Stomach

Front 1

1. What are the different types of gastric volvulus?
2. Which is most common?

Back 1

1. Gastric volvulus is associated with an intrathoracic stomach.
- Organoaxial:
- Stomach rotates along its longitudinal axis
- Greater curvature moves anteriorly and then cephalad
- GE junction remains superior to pylorus

- Mesenteroaxial:
- Stomach rotates 90° to the longitudinal axis
- Antrum and duodenum may move superior to fundus and GE junction

2. Organoaxial

Front 2

1. What are some common causes of gastritis?
2. What are the imaging findings in gastritis?
3. What neoplasm can mimic gastritis?

Back 2

1. Most common causes of gastritis include H. pylori, alcohol, and medications (NSAIDs).
2. Smooth, fold thickening involving the body and antrum of the stomach.
3. Lymphoma can also result in fold thickening resembling gastritis. Infiltrative gastric carcinomas can also simulate gastritis.

Front 3

1. What are the imaging features of erosive gastritis?
2. What are the common causes of erosive gastritis?
3. What are the differential considerations for a smooth single lesion with central crater?

Back 3

1. Punctate collections of barium surrounded by a mound of edema, often on the crest of thickened gastric folds.
2. Erosive gastritis has the same causes as garden variety gastritis -- H. pylori, infection, meds. Crohn's dz can also result in aphthous ulcers, however, additional lesions are usually present in the small bowel.
3. Erosions are always multiple. If a smooth solitary lesion with central ulceration is seen, consider pancreatic rest, GIST with central ulceration, mets.

Front 4

1. What are the imaging findings of a benign gastric ulcer?
2. What are the most common locations of the benign gastric ulcers?
3. What is the most common etiology of ulcers located along the greater curvature of the body and antrum of the stomach?
4. What is a giant ulcer?

Back 4

- Round or oval ulcer crater.
- Folds that cross the mound of surrounding edema and extend up to the crater.
- Smooth mound of edema.
- Extension of the ulcer beyond the normal gastric lumen contour
- Radiating gastric folds that are smooth and symmetric (without nodularity or clubbing)
- On tangential view of the stomach = Hampton line (non-ulcerated acid resistant mucosa)
2. Most benign ulcers occur along the lesser curvature or posterior wall of the antrum or body.
3. Ulcers that occur along the greater curvature and antrum of the stomach are associated with NSAIDs. These ulcers are sometimes referred to as "sump" ulcers. Look for a smooth mound of edema to dx them as benign.
4. Giant ulcer is larger than 3cm in diameter. They are commonly associated with contained perforations.

Front 5

1. What are the imaging findings in healing gastric ulcers?
2. What is the average time for healing of an ulcer?

Back 5

1.
- Linear configuration of the ulcer crater is often seen w/ healing ulcers.
- Ulcer crater may split into two smaller craters.
- Radiating folds may persist for a longer period.
2. 8 weeks.Therefore, f/u studies should not be performed less than 6-8 weeks after initial dx.

Front 6

What are the complications of the gastric ulcers?

Back 6

Bleeding:
- most frequent complication.
Perforation:
- look for free air.
Obstruction
Penetration:
- can penetrate into any adjacent organ or tissue.
- common sites = pancreas, omentum, biliary tract, liver, and, colon.

Front 7

1. What are the imaging findings of Zollinger Ellison syndrome?
2. What neoplasm can result in fold thickening resembling ZE and gastritis?
3. In what portion of the stomach is fold thickening associated with Menetrier disease?

Back 7

1. ZE syndrome is caused by gastrin secreting islet cell neoplasm that results in marked gastric acid hypersecretion. Increased aciditiy leads to enlarged rugal folds and peptic ulcers.
2. Lymphoma
3. Menetrier disease leads to fold thickening in the proximal stomach.

Front 8

What is the differential diagnosis of thickened gastric folds?

Back 8

1. Gastritis (H. pylori, alcohol, meds)
2. Zollinger Ellison syndrome
3. Crohn Disease
4. Varices
5. Menetrier disease
6. Lymphoma
7. Eosinophilic gastritis (elicit history of allergy)

Front 9

1. What are the imaging features of Menetrier Disease?
2. What other neoplasm can mimic fold thickening of Menetrier disease?

Back 9

1. Thickened gastric folds affecting the cardia and fundus of the stomach.
2. Lymphoma. Menetrier disease is a dx of exclusion.

Front 10

1. What are different kinds of polyps seen in the stomach?
2. Which polyps are associated with an increased risk of malignancy?
3. What is the etiology of hyperplastic polyps? In what condition are hyperplastic polyps seen in the stomach?

Back 10

1. There are 3 different kinds of polyps seen histologically. These include hyperplastic, adenomatous, and hamartomatous polyps.
2. Adenomatous polyps are often solitary and when greater than 2 cm, they have increased risk of harboring malignancy.
3. Hyperplastic polyps develop as a reactive change to chronic inflammation with mucosal proliferation. Hyperplastic polyps are associated with Familial Adenomatous Polyposis syndromes (Gardner, Turcot). When associated with FAP, they are innumerable in the stomach.

Front 11

1. What is the most common submucosal mass in the stomach?
2. What are the 3 different growth patterns?
3. What are some other causes of submucosal masses?

Back 11

1. GIST
2. Intramural, Intraluminal, and exophytic.
3. Lipoma, ectopic pancreatic rest, mets, carcinoid.

Front 12

What are the imaging findings that suggest a malignant ulcer?

Back 12

1. Floor of the ulcer crater is nodular.
2. Tissue surrounding the ulcer is nodular
3. Abrupt transition b/w the surrounding tissue and the normal gastric wall
4. Ulcer crater does not project beyond the expected location of the gastric wall.
5. Radiating folds stop at the edge of the surrounding tissue and do not reach the ulcer crater.
6. Ulcer crater is asymmetrically placed w/n the surrounding tissues.
7. Carmen meniscus sign: malignant ulcer straddles the lesser curvature of the stomach and compression is applied apposing both surfaces of the surrounding tumor.

Front 13

1. What is the pattern of metastatic gastric carcinoma?
2. What is metastatic gastric cancer to the ovary called?

Back 13

1. Gastric carcinoma starts in the mucosa and spreads to the muscle layer and further invades the serosa. Once the tumor cells reach the serosa, they can spread to the lesser and greater omentum as these structures are in contiguity with the gastric serosa. Tumor cells can also seed the peritoneal cavity.
2. Krukenberg tumor

Front 14

1. What are the imaging findings in gastric lymphoma?
2. What is the treatment of lymphoma confined to the stomach?
3. What imaging features suggest lymphoma rather than gastric adenoCA?

Back 14

1. Lymphoma can present as an infiltrative process leading to fold thickening. It can also present as solitary or multiple masses that may ulcerate.
2. Lymphoma confined to the stomach is treated surgically rather than with chemotherapy. Lymphoma confined to the stomach has a better prognosis than diseeminated disease.
3.
- Multiple lesions
- Involvement of a large extent of stomach
- Submucosal origin of the tumor
- Extension of tumor across the pylorus
- Less luminal narrowing than expected

Front 15

1. Are there any reliable ways of distinguishing a malignant from a benign GIST?
2. Do GIST present with lymph node metastases?

Back 15

1. No. There are no reliable radiographic criteria to differentiate benign from malignant GIST. However, the larger the mass,the more likely it is to be malignant.
2. GIST do not metastasize to lymph nodes. They metastasize hematogenously to the liver and peritoneal cavity.

Front 16

1. What is the imaging appearance of an ectopic pancreatic rest?
2. What does the central umbilication represent?
3. The imaging appearance of pancreatic rests is similar to what common submucosal tumor?

Back 16

1. Look for a submucosal mass with a central umbilication typically located in the antrum.
2. The central umbilication represents site at which rudimentary ducts empty.
3. GIST

Front 17

1. What are the imaging features of gastric varices?
2. What are the causes of gastric varices? How can you tell them apart?
3. What is the DDX?

Back 17

1. Serpentine filling defects in the gastric cardia and fundus.
2. Portal HTN and splenic vein occlusion. In portal HTN, there are esophageal and gastric varices, whereas, in splenic vein thrombosis there is isolated gastric varices.
3. Menetrier disease, lymphoma, adenoCA.

Front 18

1. What are the benign causes of gastric narrowing?
2. What are the malignant causes of gastric narrowing?
3. What is the "ram's horn" deformity?
4. Which tumor is responsible for "linitis plastica"? Why is histologic confirmation of this tumor difficult to obtain by endoscopic biopsy?

Back 18

1. Benign causes include chronic peptic ulcer dz, granulomatous dz (Crohn dz, sarcoidosis, TB, eosinophilic gastroenteritis), and corrosive ingestion. Chronic inflammation leads to subsequent fibrosis.
2. Malignant causes include carcinoma (scirrous adenoCA), metastasis (breast and lung), and lymphoma. NOTE: pancreatic adenoCA can invade the distal stomach by contiguous spread also producing the linitis plastica appearance.
3. Ram's horn deformity is a tubular configuration of the distal stomach seen with benign causes of gastric narrowing, especially chronic Crohn disease.
4. Scirrhous gastric adenocarcinoma and breast mets spread w/n the submucosa of the gastric wall inciting a desmoplastic reaction leading to narrowing and rigidity (linitis plastica = leather bottle). The tumor is located in the submucosal tissues and therefore a deeper biopsy is required for diagnosis.

Front 19

What are some complications that are seen in the post-operative stomach?

Back 19

1. Marginal ulcer
2. Afferent loop syndrome
3. Blown duodenal stump
4. Jejunogastric intussusception
5. Gastric remnant bezoar
6. Postgastrectomy carcinoma
7. Bile reflux gastritis

Front 20

1. What is a marginal ulcer?
2. Where are most marginal ulcers located?
3. What are the imaging features of ulcer crater?
4. What are the complications of marginal ulcers?

Back 20

1. Marginal ulcer (AKA stomal ulcer) is a PERIANASTOMOTIC ulcer that develops after a gastrojejunostomy.
2. Most marginal ulcers occur in the efferent limb of the jejunum, w/n 2 cm of the stoma.
3.
- Typical ulcer craters
- Giant ulcer craters resembling large diverticula
- Thickened jejunal folds
- Rigidity of the affected jejunal segment
4. Like ulcers anywhere, marginal ulcers may bleed, perforate, or penetrate into the colon leading to jejunocolic fistula.

Front 21

1. What are the imaging findings of afferent limb syndrome?
2. What is the preferred study to evaluate for afferent limb syndrome? Why?
3. What are the causes of obstruction resulting in afferent limb syndrome?

Back 21

1. Marked distention of the afferent limb due to obstruction.
2. CT is the preferred imaging modality as it clearly depicts the dilated afferent limb. UGI studies often do not demonstrate opacification of the afferent limb.
3. Causes of afferent limb obstruction include:
- Adhesions
- Ulcer with inflammation leading obstruction
- Recurrent tumor
- Internal hernia
- Nonphysiologic surgical anastomosis: food preferentially empties into the afferent limb.

Front 22

1. What is the time course of post-gastrectomy carcinoma?
2. Why is there an increased risk of gastric carcinoma in pts who have undergone gastroenterostomy for ulcer disease?

Back 22

1. Recurrent gastric carcinoma after gastroenterostomy can occur within several months of surgery due to subtotal tumor removal. It can also occur as a primary cancer developing 20-30 years after gastric surgery for ulcer disease.
2. There is an increased risk of gastric carcinoma due to reflux of bile acids and pancreatic secretions into the stomach.

Front 23

1. What is the most common location of gastric diverticula?
2. What can the diverticulum be confused with at this location?
3. What is a partial gastric diverticulum?

Back 23

1. Most diverticula arise from the posterior surface of the gastric fundus near the GE jxn. Look for gastric folds extending into the diverticulum.
2. It can be confused with an adrenal mass.
3. Protrusion of gastric mucosa into the muscular wall of the stomach. It can be confused with a peptic ulcer. NOTE: Diverticula change shape whereas ulcer does not change.

Front 24

What are the causes of emphysematous gastritis?

Back 24

1. Infection: pts are severely ill; E. Coli, Clostridium perfringes
2. Gastric outlet obstruction with associated increased intragastric pressure.
3. Corticosteroids

Front 25

What cancers like to metastasize to the stomach?

Back 25

Breast and melanoma

Front 26

Wha are the complications of lap band?

Back 26

1. erosion of the device into the gastric lumen, resulting in the leak of gastric contents,
2. slip or rotation of the device that may cause gastric obstruction.