Biliary Manometry in Choledochal Cyst with Abnormal Choledochopancreatico Ductal Junction

Intraoperative manometry of the biliary tract and measurement of amylase levels in choledochal cysts were performed in seven patients, aged 14 months to 5 years, with choledochal cysts, in an investigation of the pathophysiology of the biliary tract. An abnormal choledochopancreatico ductal junction was observed in these seven patients by preoperative endoscopic retrograde cholangiopancreaticography (ERCP) or intraoperative cholangiograms. All six patients examined showed a high amylase level in the choledochal cyst (5,450 to 46,500 Somogyi Units). The intraoperative manometry of the biliary tract showed that a remarkable high pressure zone as was found in the area of sphincter of Oddi was not found in the area of abnormal choledochopancreatico ductal junction. The pressure recordings also demonstrated that the sphincter of Oddi pressure in the patient with choledochal cyst was increased by gastrin stimulation. On the contrary, no pressure reaction to gastrin or secretin was found in the area of abnormal choledochopancreatic ductal junction. From these results it seems that free reflux of pancreatic juice into the biliary system occurs, and the reflux stream depends upon the pressure gradient between pancreatic ductal pressure and common bile duct pressure because of the lack of a sphincter function at the choledochopancreatico ductal junction.