Imaging of the small bowel.

Radiologic imaging continues to play an integral role in the diagnosis and management of diseases of the small bowel. Except for the most proximal jejunal loop, which may occasionally be reached during upper gastrointestinal tract panendoscopy, and the terminal ileum, which can frequently be examined by the colonoscope, the mesenteric small intestine is the only gastrointestinal tract segment for which diagnostic study is not principally dependent upon endoscopic viewing. To the extent that radiologists assume primary responsibility in the diagnostic evaluation of the small bowel, it is essential that methods capable of accurately demonstrating small bowel morphology are appropriately applied (Maglinte et al., Radiology 1987, 163:297-305). Barium contrast studies and enteroclysis in particular remain the primary diagnostic methods in the small bowel for most clinical indications. Cross-sectional imaging modalities often provide unique diagnostic information, but their role remains either complementary to the demonstration of surface details by barium contrast studies or directed toward specific clinical circumstances that require discrete evaluation of the small-bowel wall and the adjacent tissues and organs.