35 Narrowing of the Colon

CLINICAL IMAGAGINGAN ATLAS OF DIFFERENTIAL DAIGNOSIS

EISENBERG

DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

• Fig GI 35-1 Chronic ulcerative colitis. Fibrosis and muscular spasm cause shortening and rigidity of the colon and a loss of haustral markings.

• Fig GI 35-2 Benign stricture in chronic ulcerative colitis. In addition to the severe narrowing in the sigmoid colon (closed arrow), there are ulcerative changes in the upper rectum and proximal sigmoid colon (open arrow).

• Fig GI 35-3 Chronic Crohn's colitis. Foreshortening and loss of haustra involving the colon distal to the hepatic flexure simulate the appearance of chronic ulcerative colitis.

• Fig GI 35-4 Ischemic colitis. A stricture in the descending colon (arrow) followed healing of the ischemic episode.45

• Fig GI 35-5 Amebiasis. Irregular constricting lesion in the transverse colon. The relatively long area of involvement tends to favor an inflammatory etiology.

• Fig GI 35-6 Radiation injury. Smooth stricture of the rectosigmoid developed 18 months after irradiation.

• Fig GI 35-7 Cathartic colon. Bizarre contractions with irregular areas of narrowing primarily involve the right colon. Although the ileocecal valve is gaping, simulating ulcerative colitis, no ulcerations are identified.

• Fig GI 35-8 Caustic colitis. Narrowing of the midtransverse colon 2 months after a detergent enema.46

• Fig GI 35-9 Annular carcinoma of the sigmoid colon. The relatively short lesion (arrow) has sharply defined proximal and distal margins.

• Fig GI 35-10 Scirrhous carcinoma of the colon. The long, circumferentially narrowed area (arrow) simulates segmental colonic encasement due to metastatic disease.

• Fig GI 35-11 Intraperitoneal metastases from carcinoma of the pancreas. The nodular mass in the region of the pouch of Douglas (arrows) was clinically palpable (Blumer's shelf).

• Fig GI 35-12 Intraperitoneal seeding of undifferentiated carcinoma involving the sigmoid mesocolon. There is a mass effect and tethering localized to the superior border of the sigmoid colon (arrow).

• Fig GI 35-13 Carcinoma of the colon developing in a patient with long-standing chronic ulcerative colitis. There is a long, irregular lesion with a bizarre pattern in the transverse colon. Note the pseudopolyps in the visualized portion of the descending colon.

• Fig GI 35-14 Acute sigmoid diverticulitis. Severe spasm of the sigmoid colon due to the intense adjacent inflammation. Note the thin projection of contrast material (arrow) representing extravasation from the colonic lumen.

• Fig GI 35-15 Rectal stenosis due to suppositories of Veganine.47