OBJECTIVETo investigate the relationship between anatomic abnormalities and malfunction of Oddi sphincter with formation of bile duct pigment gallstone.

METHODSOne hundred and twenty-three patients with a T tube after cholecystectomy and choledochotomy were divided into reflux group and control group by measuring the amounts of radioactivity of (99m)Tc-DTPA in the bile. Among them 53 were selected randomly to undergo choledochoscopic manometry. Basal pressure of Oddi's sphincter (SOBP), amplitude of Oddi's sphincter (SOCA), frequency of contraction (SOF), duration of contraction (SOD), duodenal pressure (DP), common bile duct pressure (CBDP) were scored and analyzed. The level of plasma motilin and serum gastrin of 45 patients and 12 healthy volunteers were measured by radioimmunoassay. The incidence rates of duodenal descending part diverticulum in patients with bile duct pigment stones, patients without alimentary tract diseases, patients with gallbladder polyps, patients with gallbladder stones were studied by means of barium meal examination. The incidence rates of intraduodenal peri-ampullary diverticulum in patients with primary bile duct pigment stones, patients with bile duct stone and gallbladder stones, patients with bile duct stones originating from the gallbladder, patients with inflammation and stricture of the extremity of bile duct and papilla, patients with cancer of the extremity of bile duct and papilla, patients with post-cholecystectomy syndrome were detected by duodenoscope.

RESULTSOf the patients, 44 were detected with duodenal-biliary reflux (35.8%). SOBP, SOCA and CBDP in the reflux group were much lower than those in control group (P < 0.001). The level of serum gastrin and plasma motilin of the reflux group were much lower than those of control group (P < 0.01). Positive correlation was found between level of motilin and SOBP while level of gastrin was positively correlated with SOBP and CBDP. The incidence of duodenal diverticulum in patients with bile duct pigment stone was 36.62%, which was higher than that of the other 3 groups. The incidence rate of intraduodenal peri-ampullary diverticulum in patients with primary bile duct pigment stone was higher than that of patients with inflammation and stricture of the extremity of bile duct and papilla, patients with cancer of the extremity of bile duct and papilla and patients with bile duct stones originating from the gallbladder.

CONCLUSIONSThe patients with bile duct pigment stone have apparent duodenal-biliary reflux and infection of the bile duct. The state of structure and function of Oddi's sphincter is correlated significantly with bile duct pigment stone. The anatomic abnormalities and malfunction of Oddi's sphincter played an important role in the formation of bile duct pigment stone.