Diagnostic value of ultrasound in duodenal stenosis.

Radiology and endoscopy are usually used to diagnose stenosis of the duodenum, but the cause of the stenosis may still escape detection. Three pathologic processes--multiple duodenal polyps, duodenal wall cysts, and annular pancreas--are presented to demonstrate how ultrasound, under specific conditions, can provide decisive diagnostic information. The cause of the stenosis may be made accessible to sonographic study through administration of oral fluids and intravenous hyoscin-n-butylbromid (Buscopan).