Computed tomography of Crohn's disease--reevaluation.

The indications and CT features of Crohn's disease were reevaluated, based on 48 examinations in 28 patients. Although CT is indicated mostly in the complications of Crohn's disease, it played a major role in the primary diagnosis of Crohn's disease in 8 patients. 5 unsuspected patients had CT for other abdominal indications and 3 had the examinations as part of an elective diagnostic work-up. The following CT features of Crohn's disease are worthy of note: Bowel wall thickening is usually obvious and needs no measurement. Abscesses are often of inhomogeneous density and should be differentiated from inflammatory bowel conglomerates. Late CT scans can be helpful in this respect. Fistulae are not well demonstrated directly by CT. The fistulogram remains the examination of choice, when possible. Mesenteric lymphadenopathy is small and discrete. Mesenteric lipomatosis can be massive and is often a cause of bowel separations and mass effect.