Protection of Oddi's sphincter remains a huge argument especially in the long term complications like common bile duct stone recurrence or cholangitis after ERCP, which determined to destroy the sphincter of Oddi. The purpose of this study is to compare the long-term outcomes of ERCP sequential LC versus LCBDE for choledocholithiasis.

Cholelithiasis, a common etiology factor responsible for abdominal pain, is highly prevalent worldwide. According to data from general investigation, the morbidity of cholelithiasis differs from 2.36% to 42% in different areas, and about 5% to 29% (average 18%) of all cholelithiasis cases have both gallbladder stone and common bile duct stone. In the population with age above 70 years old, 30% of which suffers from gallbladder stone in China. A causal link between the development of gallbladder stone and common bile duct stone is that 10% to 15% of gallstone patients have high potential to develop secondary common bile duct stone. In 1987, the laparoscopic cholecystectomy (LC) came into being as a revolutionary surgical method. With minimally invasive effect and high safety, LC was soon accepted as a 'Golden standard' for the treatment of gallbladder stone. Endoscopic sphincterotomy (EST) was firstly reported by Kawai and Classen in 1970. As of now, the combination of EST with other endoscopic techniques, such as basket extraction, balloon dilation and lithotripsy, have significantly improved the stone removal rate from 85% up to 90%, and ERCP has been considered as the optimal method in regard to CBD stone treatment. In 1991, the laparoscopic common bile duct exploration (LCBDE) which reflected the advantage of rigid scopes had risen to be a very promising minimally invasive alternative for the treatment of common bile duct (CBD) stone. Currently, there are mainly two kinds of minimally invasive treatments for choledocholithiasis, which refers to the "one-stage" laparoscopic method, LCBDE and the "sequential two-stage" method, ERCP followed by LC. Both methods are able to achieve the same therapeutic purpose. However, there has always been a controversy about the advantages and disadvantages due to lack of evidence from long-term follow-ups, especially the difference of long-term complications related to Oddi's sphincter functional status, which importantly refers to stone recurrence rates and cholangitis.

The potential long-term complications resulted from EST remains an issue now. It is believed that EST handles Oddi's sphincter stenosis, regurgitation cholangitis, and higher cholangiocarcinoma risks in a long run. By virtue of ERCP, multiple high stone clearance rates (87%~97%) were reported, but meanwhile high re-ERCP rates (around 25%) were also indicated because of stone residual, and whether great stone residual rates was linked to future stone recurrence and repeated cholangitis is not clear. Several randomized controlled trial (RCT) studies had compared ERCP plus LC and LCBDE, the results were similar to the aspects of stone removal rates, costs, and patient acceptance. However, the postoperative cholangitis rate of one single center study is quite different from another. Moreover, few studies have related the stone recurrence rate in the long term follow-up. Obviously, previous RCT studies were limited by few comparison of ERCP followed by LC versus LCBDE in long-term complications, especially stone recurrence and cholangitis. Therefore, this multicenter randomize control study is designed prospectively to compare the stone recurrence and cholangitis rates between ERCP plus LC and LCBDE which can reflects the valuable of Oddi's sphincter protection during the disease management, further dedicating the treatment of gallbladder and common duct stone.

Inclusion Criteria:

• Age 18-65 years old
• Choledocholithiasis patient did not perform any operation
• Common bile duct stone less than 2cm in maximum diameter

Exclusion Criteria:

• Unwillingness or inability to consent for the study
• Coagulation dysfunction (INR> 1.3) and low peripheral blood platelet count (<50×109 / L) or using anti-coagulation drugs
• Previous EST, EPBD or percutaneous transhepatic biliary drainage (PTBD)
• Prior surgery of Bismuth Ⅱ and Roux-en-Y
• Benign or malignant CBD stricture
• Preoperative coexistent diseases: acute pancreatitis, GI tract hemorrhage, severe liver disease, primary sclerosing cholangitis (PSC), septic shock
• Combined with Mirizzi syndrome and intrahepatic bile duct stones
• Malignancies
• Biliary-duodenal fistula confirmed during ERCP
• Pregnant women