Abstract
From May 1990 through April 1997, endoscopic retrograde cholangiopancreatography (ERCP) was performed in 1210 patients, of whom 652 were chosen as subjects of this study. We devised a new morphologic classification of the papilla of Vater. Forms of the protuberance of the major papilla were classified into three types : spherical type, flat type and irregular type. The opening of the pancreaticobiliary duct was classified into two types : spot type and elongated type. The epithelium around the opening was classified into two types : granular type and villous type. We studied these forms, separate openings of the pancreaticobiliary duct, the presence of oral protrusion and frenulum, presence of anomalous connections of the pancreaticobiliary ducts, abnormal adherence of the cystic duct, relation to cholangiopancreatic diseases in flat and irregular types. We conclude that a larger proportion of cases were of the elongated and villous types and were of separate openings in the flat and irregular types than the spherical type. All cases of the flat and irregular types tended to have oral protrusion and many cases of the irregular types did not have a frenulum. An anomalous connection of the pancreaticobiliary duct was noted in one case of the flat type, and abnormal adherence of the cystic duct was noted in no cases of either the flat or irregular type. An association with pancreas cancer was noted in cases of the flat and irregular types. Therefore, if an unusual form of the papilla of Vater is confirmed, it may be necessary to perform further examinations of the pancreaticobiliary tract such as computed tomography and magnetic resonance cholangiopancreatography.
