Radiologic diagnosis of Crohn disease (with emphasis on its early manifestations).

Crohn disease can affect any part of the gastrointestinal tract. The early manifestations of the disease are readily recognizable in the colon if double-contrast technique is employed. Small bowel and gastroduodenal involvement in the early stages have been less frequently identified, but enteroclysis and double-contrast UGI examination have yielded encouraging results. There is some evidence that failure to utilize the double-contrast barium enema and enteroclysis contributes to delay in diagnosis of Crohn disease. Use of these more sophisticated techniques is encouraged. As follow-up radiography in Crohn disease appears less indicated than previously considered, it is particularly important that initial assessment employs the most sensitive and accurate radiographic techniques available.