THREE CASES OF ANNULAR PANCREAS ; DIAGNOSTIC VALUE OF ERCP, CLINICAL AND ETIOLOGICAL ASPECTS

Abstract

Three cases of annular pancreas in adult are described with emphasis on the value of ERCP procedure for the diagnosis and etiological consideration of this anomaly. The first patient is a 47-year-old-male. ERCP revealed a short main pancreatic duct and branches of the duct of Santorini encircling the duodenum near the papilla of Vater. Intrahepatic bile duct stones were also found. The second patient is a 21-year-old female having a history of pancreatitis. The proximal second portion of the duodenum was encircled by branches of the duct of Wirsung on ERCP. She had a small stone in the gallblader. The third patient is a 67-year-old male. ERCP demonstrated that the duct of annular portion was originated from the duct of Wirsung. The demographic and presenting clinical features among welldescribed 93 cases of annular pancreas in adult reported in Japanese literature were as follows ; a ratio of male to female was 7 to 3, the mean age was 44.9 years and abdominal pain or discomfort and nausea were the majar symptoms. The most leading complications reported were pepticulcer and cholelithiasis, each in the frequency of 21.6% and pancreatitis in 14.4%. The etiology of annular pancreas has not been fully clarified. The analysis of type of the opening site for annular pancreatic ducts by ERCP was considered to be useful for elucidating the evolution of annular pancreas. Many of the cases reported in the literature showed connection of annular pancreatic duct to the duct of Wirsung, so that this anomaly was considered to be derived from the ventral pancreas as described by Lecco. In some cases, however, the corresponding duct of annular pancreas originated from the duct of Santorini as observed in our first case. Therefore, the participation of dorsal pancreas or anomalous evolution of duodenum should be taken into consideration in the etiology of annular pancreas. We believe that ERCP can provide a useful procedure not only for the diagnosis but also for the clarification of the evolutional aspects of annular pancreas.