Surgical significance of dilatation of the common bile duct--with special reference to choledocholithiasis.

Diameter of the common bile duct was measured in 3,119 patients who underwent primary operation for gallstones, during the period from 1975 to 1978. Although dilatation of the common bile duct was most marked in patients with bilirubin stones in the bile duct alone, dilatation was also observed in patients with cholesterol stones in the gallbladder alone. Drip infusion cholangiograms of 84 healthy patients showed that the common bile duct dilated in parallel with aging. A review of patients with congenital choledochal cysts reported in the literature in Japan revealed that few had gallstones. Thus, it was difficult to determine whether common bile duct dilatation was the cause or result of gallstones, and it was suggested that the so-called drainage operation such as choledochoenterostomy should be done only under strict indications.