Prevalence of common bile duct stones according to the increasing number of risk factors present. A prospective study employing routinely intraoperative cholangiography in 477 cases.

BACKGROUND/AIMS: To determine if the use of Intraoperative choliangiography (IOC) should be routinely performed and, if not, which criteria should be used to select patients requiring IOC during open or laparoscopic cholecystectomy.

METHODOLOGY

495 Patients with 1 or more gallstones were included in a two-year study. Twelve clinical, laboratory, ultrasonographic and intraoperative factors were chosen and evaluated in all cases. Prior to cholecystectomy, IOC was performed after having identified the common bile duct (CBD) and cystic duct. The majority of the patients were operated on by the same surgeon to avoid differences in criteria and techniques. Statistical evaluation made use of the exact Fisher test and chi square test and, a p-value less than 0.05 was considered as significant.

RESULTS

IOC could be performed in 479 out of the 495 cases. IOC resulted in a normal CBD in 76.0%, had a false positive in 2.7%, a false negative in 0.48%, and a presence of 1 or more stones in the CBD in 20.9%. The study revealed that when none of the 12 risk factors were present, there were no cases with CBD stones. As the number of risk factors increased, so did the number of cases presenting with CBD stones.

CONCLUSION

Not all 12 risk factors show the same index of predictability; only 5 in particular (jaundice, ultrasound diameter CBD 7 mm, bilirubin over 26 umol/it, cystic duct > 4 mm and CBI, diameter over 9 mm) showed a high rate of predictability. However, when careful measurement and evaluation of risk factors for CBD stones are undertaken, it is possible to avoid the routine use of IOC.