The study compares two different methods to evaluate extrahepatic bile ducts for possible stones for patients with cholecystolithiasis and intermediate risk for choledocholithiasis when laparoscopic cholecystectomy is indicated.

Endosonoscopic evaluation of bile ducts and endoscopic retrograde cholangiography (ERCP) on demand are performed before laparoscopic cholecystectomy for one arm. Intraoperative cholangiography during laparoscopic cholecystectomy and postoperative ERCP on demand are administered in another arm.

Use of ERCP as a diagnostic tool should be minimized as it carries considerable risk (5 to 10%) of post-procedural complications. It is noticed that adverse events occur more often to patients with low risk of choledocholithiasis. Therefore the best possible patient selection for ERCP procedure is needed.

At the Centre of Abdominal Surgery of Vilnius University Hospital Santaros klinikos an original prognostic index (Vilnius University Hospital index (VUHI)) is used for evaluation of risk of choledocholithiasis. It is calculated by formula VUHI = A/30 + 0.4×B, where A - total bilirubin concentration (µmol/l), B - common bile duct (CBD) diameter measured by ultrasound exam. A retrospective study evaluated its accuracy and determined threshold values for low, intermediate and high risk groups. The intermediate risk group (risk for choledocholithiasis 25-75%) would benefit from additional examination before ERCP. Endoscopic ultrasound (EUS) and intraoperative cholangiography are less invasive procedures with high accuracy identifying common bile duct stones. Main hypothesis of the trial is that intraoperative cholangiography with ERCP on demand can shorten the duration and costs of treatment and avoid diagnostic ERCPs.

Inclusion Criteria:

• patients with cholecystolithiasis when laparoscopic cholecystectomy is indicated
• intermediate risk for choledocholithiasis (VUHI 2,6 - 6,9 and one of the predictors: dilated common bile duct, elevated total bilirubin or suspected stone in CBD on ultrasound)

Exclusion Criteria:

• pregnancy;
• acute cholangitis;
• biliary pancreatitis;
• acute cholecystitis, degree II-III by Tokyo guidelines 2013;
• anastomosis in upper gastrointestinal tract;
• other known cholestatic hepatopancreatobiliary disease;
• known or suspected hepatitis of another origin (viral, toxic, etc.);
• contraindications for general anaesthesia or surgery;
• IV-VI class of American Society of Anesthesiologists physical status classification;
• morbid obesity (body mass index > 40);
• patient's refusal to participate in the study.