[Radiologic evaluation of Crohn disease]

This paper discusses the role of different imaging modalities in the diagnostic work-up of Crohn's disease (CD).

We present a concept, which emphasizes different diagnostic aspects with regard to primary diagnosis, follow-up and assessment of complications of CD. The most effective imaging approach to various diagnostic problems of CD is discussed in detail.

With regard to the primary diagnosis barium studies should contribute to differentiate between CD and ulcerative colitis. Beyond that, these studies should evaluate location and extent of disease. During the follow-up bowel sonography provides staging of disease and enables the detection of complications at an early stage. CT is a valuable tool in the preoperative assessment of complications, such as fistulae and abscesses.