The instant enema in inflammatory disease of the colon.

The instant, or unprepared, double contrast barium enema has been used routinely at St Mark's Hospital in the investigation of active inflammatory disease of the colon since 1963. The use of air contrast is preferred to show the fine detail of the mucosal changes and to detect early involvement. With the instant enema technique the diagnostic results are satisfactory and patients are minimally disturbed by the procedure. The majority of examinations consist of a total of four films, which includes a plain film of the abdomen prior to the administration of contrast. For short-term follow-up a repeat enema with a single film is usually adequate.