Pancreatitis in the annulus of annular pancreas demonstrated by the combined use of computed tomography and endoscopic retrograde cholangiopancreatography.

Annular pancreas, an uncommon condition, is often hard to diagnose before operation. We report a case of annular pancreas with pancreatitis of the annulus that was diagnosed by the use of computed tomography followed by endoscopic retrograde cholangiopancreatography. An upper gastrointestinal series and duodenoscopy revealed stenosis of the second portion of the duodenum. Computed tomography revealed enlargement of the annulus of the pancreas. Two years later, follow-up computed tomography demonstrated calcifications of the annulus, although the remaining pancreas seemed to be normal.