Asymptomatic bile duct stones: selection criteria for intravenous cholangiography and/or endoscopic retrograde cholangiography prior to laparoscopic cholecystectomy

Objective Routine use of endoscopic retrograde cholangiography (ERC) and/or intravenous cholangiography (IVC) or magnetic resonance cholangiopancreato graphy (MRCP) before laparoscopic cholecystectomy (LC) is not cost-effectiv e. The objective of this study was to determine precise and easily applicab le criteria to select patients who should undergo IVC, MRCP and/or ERC befo re LC. Design and methods Prospectively collected data from 74 consecutive patient s who were diagnosed with asymptomatic common bile duct stones (CBDS) befor e undergoing LC, were compared with data from 74 matched controls without C BDS, Using the chi (2) test, those variables were identified which were sig nificantly related to the presence of CBDS, These were inserted into a logi stic multiple regression model and, by means of conditional regression anal ysis, each variable was assigned a score from -2 to +4 proportional to the odds ratio. By adding up the scores obtained, a classification was made as to high, medium and low CBDS risk. Results As a result, 51 patients were found to be low-risk cases, 53 medium -risk and 44 high-risk. Assuming no further assessment of the bile duct nee ded to be carried out in low-risk patients, an IVC or MRCP in those at medi um risk and an ERC in those at high risk, a calculation was made of the pos itive predictive value and the sensitivity of the system proposed. The posi tive predictive value and the sensitivity of the procedure were calculated as being greater than 90%. Conclusions This predictive system for the risk of CBDS allows the selectiv e use of ERC, IVC and MRCP to ensure a high yield and improve cost-effectiv eness. A controlled prospective study will verify these results. (C) 2000 L ippincott Williams & Wilkins.