[Observations on the function of Oddi's sphincter in patients with primary bile duct stones].

We recorded the pressure of Oddi's sphincter (SO) in 54 patients with gall stones and 25 patients as controls who had no biliary disease. Endoscopic manometry used in this study recorded the dynamic changes of the intraluminal pressure of SO as well as the static pressure of the common bile duct. It was found that in control group, common bile duct pressure was 1.54 +/- 0.15 kPa, basic pressure of SO 2.12 +/- 0.22 kPa, SO-bile duct pressure difference 0.58 +/- 0.07 kPa, and SO peak pressure 5.56 +/- 0.47 kPa, respectively. There was no significant difference between patients with gallbladder stones and secondary cholelithiasis and those in control group. But the pressure of SO was significantly lower in patients with primary bile duct stones than that in controls. This phenomenon indicates that in such patients the contraction strength of SO is weak or lost. This may explain retrograde cholangitis often seen in some patients. We suggest that in order to prevent retrograde cholangitis, adequate procedure should be taken in operation on patients with functional impairment of SO.