Incidence of residual choledocholithiasis detected by intraoperative cholangiography at the time of laparoscopic cholecystectomy in patients having undergone preoperative ERCP.

Introduction: The purpose of this study is to determine the incidence of residual common bile duct (CBD) stones after preoperative ERCP for choledocholithiasis and to evaluate the utility of routine intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC) in this patient population.
Methods: All patients who underwent preoperative ERCP and interval LC with IOC from 5/96 to 12/05 were reviewed under an Institutional Review Board (IRB)-approved protocol. Data collected included all radiologic imaging, laboratory values, clinical and pathologic diagnoses, and results of preoperative ERCP and LC with IOC. Standard statistical analyses were used with significance set at p < 0.05.
Results: A total of 227 patients (male:female 72:155, mean age 51.9 years) underwent preoperative ERCP for suspicion of choledocholithiasis. One hundred and eighteen patients were found to have CBD stones on preoperative ERCP, and of these, 22 had choledocholithiasis diagnosed on IOC during LC. However, two patients had residual stones on completion cholangiogram after ERCP and were considered to have retained stones. Therefore, 20 patients overall were diagnosed with either interval passage of stones into the CBD or a false-negative preoperative ERCP. In the 109 patients without CBD stones on preoperative ERCP, nine patients had CBD stones on IOC during LC, an 8.3% incidence of interval passage of stones or false-negative preoperative ERCP. In both groups, there was no correlation (p > 0.05) between an increased incidence of CBD stones on IOC and a longer time interval between ERCP and LC, performance of sphincterotomy, incidence of cystic duct stones, or pathologic diagnosis of cholelithiasis.
Conclusions: The overall incidence of retained or newly passed CBD stones on IOC during LC after a preoperative ERCP is 12.9%. Although the natural history of residual CBD stones after preoperative ERCP is not known, the routine use of IOC should be considered in patients with CBD stones on preoperative ERCP undergoing an interval LC.