PREDICTION OF COMMON BILE-DUCT STONES - ITS VALIDATION IN LAPAROSCOPIC CHOLECYSTECTOMY

Background/Aims: Although perioperative cholangiography is valuable an d highly accurate in. the detection of common bile duct (CBD) stones, its routine use is controversial, particularly in the era of the lapar oscopic cholecystectomy because of its inherent disadvantages. The pur poses of this retrospective and prospective study on cholelithiasis we re to identify patients at low risk for CBD stones and to assess the v alidity of the low risk criteria. Methodology: For the first, retrospe ctive study, 15 significant preoperative clinical, biochemical and son ographic variables were selected from 561 consecutive patients who und erwent conventional cholecystectomy with routine intraoperative cholan giography (IOC) for cholelithiasis from January 1985 to December 1993, and independent risk factors predicting the presence of CBD stones we re determined by multivariate logistic regression analysis. For the se cond, prospective study, from April 1994 to September 1995, a laparosc opic cholecystectomy (LC) was performed without perioperative cholangi ography in 153 consecutive patients with the primary bow risk criterio n (sonographic CBD diameter <10mm) determined by the first study. All of the LC patients were followed-up for a median duration of 12 months (range 4 to 21 months). Results: In the first study, CBD stones were present in 95 (16.9%) patients. The most important independent predict or was a dilated CBD (>10mm). Three levels of risk were determined: (1 ) the low risk group (73.8% of the patients), in which the CBD was not dilated and the prevalence of CBD stones was 1.5% (6/408); the modera te risk group (7.8% of the patients), in which there was a dilated CBD with normal liver function tests and a prevalence of stones of 48.8% (21/43); and the high risk group (18.4%), in which there was a dilated CBD and abnormal liver function tests and a prevalence of stones of 6 6.7% (68/102). In the second study, two cases (1.4%) of symptomatic ov erlooked CBD stones were found on endoscopic retrograde cholangiograph y and retrieved by endoscopic sphincterotomy on postoperative days 18 and 20, respectively. Conclusions: Preoperative assessment in cases of cholelithiasis can determine which patients are at low risk for havin g CBD stones, thereby avoiding unnecessary perioperative cholangiograp hy. This selectivity is also valid in. LC, since the incidence of symp tomatic, overlooked CBD stones was very low.