We carried out a retrospective study analyzing the cases of 107 patients with acute pancreatitis of biliary origin who underwent cholecystectomy with OPC. VBP vacuity accounted for 80.4% of cases. Univariate analysis revealed 6 independent factors for the presence of LVBP: total bilirubin level, conjugated bilirubin level, VBP dilatation on ultrasound, VBP dilatation on CT, stage of pancreatitis and cystic duct dilatation intraoperatively. Multivariate analysis enabled us to retain only 2: total bilirubin level and dilatation of the VBP on ultrasound. This rate was set at 34.5 by studying the ROC curve.we established a mathematical translation of these 2 factors in the form of a simple score in order to test our results.S = E + 0.03 BTE = 1 if dilatation of the VBP on ultrasound. E = 0 if no dilatation of the VBP. BT = total bilirubin level in mmol/l.A score greater than or equal to 1 would indicate the need for intraoperative cholangiography during cholecystectomy.