Inflammatory Bowel Diseases

Abstract

The term inflammatory bowel disease covers a group of disorders of the gastrointestinal tract caused by an immune reaction to the intestinal wall, and the two major types are ulcerative colitis and Crohn’s disease. Ulcerative colitis is limited to the large bowel with primary mucosal involvement; meanwhile, in Crohn’s disease, any part of the gastrointestinal tract may be involved, with transmural lesions. Both are intermittent diseases, with periods of exacerbated symptoms, and periods that are relatively symptom-free.

CT colonography is not commonly used in patients with inflammatory bowel disease. The potential indication to study such patients with CT colonography is the detection of polyps and masses, since it is well known that these patients carry an increased risk of colorectal cancer. All mucosal alterations of inflammatory bowel disease are beneath the spatial resolution of CT. Consequently, when the disease is limited to the mucosa, CT scans usually are normal. CT colonography patterns of the advanced stages of inflammatory bowel diseases are described in the chapter.