Technical steps to extract transcystic approach include: dissect ion of the cystic duct for recognizing the confluence of the cystic duct withthe common bile duct, longitudinal incision ismade on the anterior wall of the cystic duct and then insertion of a choledochoscope into the common bile duct to eliminatestone. Technical stepstransductal approach includes: make a choledochotomy on the long axis of the common bile duct, then insert the choledochoscope through choledochotomy to eliminatestone.