Abstract:Objective: To investigate the feasibility and safety of direct choledochoscopy in the diagnosis and treatment of residual stones after ERCP. Methods: 20 cases of extrahepatic bile duct stones treated with ERCP were selected from January 2016 to January 2018 in the first affiliated hospital of xiamen university, followed by routine ERCP and DPOC treatment. The success rate of DPOC, arrival location, positive rate, operation time, complications were observed.Results: DPOC were successfully inserted into the common bile duct in 19 cases of 20 patients ,and failed in 1 case.The residual stones were found in 9 cases and no residual stones were found in 10 cases. 5 cases reached the common bile duct,7 cases reached the hepatic portal,,3 cases reached the right and left hepatic duct,and 4 cases reached the level 2 bile duct.The average operating time was 11.7min.Complications: postoperative pancreatitis and hemorrhage occurred in 1 case, and cholangitis in 2 cases. Conclusion: The diagnosis and treatment of residual stones after ERCP by DPOC is feasible and reliable, and the stone clearance rate is high to avoid stone residue.