ANNULAR PANCREAS AS A RARE DIFFERENTIAL-D IAGNOSIS OF ADULT DUODENAL OBSTRUCTION

Annular pancreas is a rare congenital malformation of the pancreas. In about 50% of the cases the malformation is asymptomatic until the thi rd to fifth decade. We report on a 52-year-old male patient who presen ted with subtotal duodenal and gastric outlet stenosis. Duodeno-hemipa ncreatectomy (Whipple's procedure) was performed. The histological exa mination showed an annular pancreas with complicating inflammatory rea ctions (tryptic sialadenitis) of the pancreatic head causing additiona l obstruction. Annular pancreas should be taken into account as a poss ible cause of adult duodenal obstruction. Endoscopic retrograde cholan giopancreatography (ERCP)is the diagnostic modality of choice, and in combination with computed tomography the diagnosis can be obtained pre operatively in many patients. However, there are still patients in who m the diagnosis can finally be obtained only intraoperatively especial ly in cases where inflammatory pseudotumors or subtotal duodenal steno sis make ERCP impossible.