Crohn’s Disease - RADIOGRAPHY

Posted by Alex

Radiographic examination should begin with a supine and upright view of the abdomen. Associated findings of nephrolithiasis, cholelithiasis, or arthritis of the spine or sacroiliac joints may be identified. Intestinal dilatation or air-fluid levels suggesting obstruction preclude aggressive barium studies until the patient’s clinical condition is stabilized. In colitis, a plain view of the abdomen often demonstrates a tubular, ahaustral segment of colon in the presence of distal UC with fecal matter proximal to diseased mucosa. Intestinal edema, ulceration, or thumb-printing may give a gross estimate of disease activity. Air-contrast barium studies of the colon reveal diffuse, contiguous granularity, superficial ulceration, and absent haustration in active UC. Pseudopolyps or a tubular-appearing “lead pipe” colon may be found in chronic UC. Focal, asymmetric ulceration with linear or fissuring ulcers, the presence of fistulas, rectal sparing, or a diseased terminal ileum with reflux of the barium define the radiographic extent and severity of colonic CD. A small bowel follow-through or enteroclysis (small bowel enema) demonstrates the extent of small intestinal involvement in CD and is normal in the absence of backwash ileitis in UC.

Specialized diagnostic imaging studies are occasionally useful to diagnose the extent or complications of IBD. Ultrasonography (US) or a computed tomography (CT) examination can clarify the presence of thickened bowel wall and mesentery versus an abscess cavity in an abdominal mass. Perineal CT scan or rectal US demonstrates the degree of involvement and the complexity of anorectal fistulas. Occasionally, US- or CT-guided aspiration of a cavity can reduce the morbidity of abdominal or retroperitoneal suppuration. Injected indium- or technetium-labeled leukocytes localize in sites of intestinal inflammation, and fecal excretion of radiolabeled leukocytes can be a measure of inflammatory activity.