110 patients with common bile duct (CBD) stones and had one or more anther preoperative predictors for high risk for difficult cholecystectomy admitted to departement of surgery of Minia university hospital for ERCP then laparoscopic cholecystectomy (LC). the patient divided into 2 equal group. in group 1, nasobiliary (NB) catheter was inserted during ERCP after CBD clearance. In group 2, only CBD clearance was done. In all patients LC was done within the same week of ERCP. Tans-nasobiliary Intraoperative cholangiography was done and methylene blue injected at the end of the procedure to detected any leak in NB group

110 patients with common bile duct (CBD) stones and had one or more anther preoperative predictors for high risk for difficult cholecystectomy as , age > 65 , male sex, obesity, acute cholecystitis, previous upper abdominal surgery, and certain ultrasonographic findings i.e. distended gall bladder (GB), thickened GB wall, pericholecystic fluid collection and impacted stone etc. these patients admitted to department of surgery of Minia university hospital for ERCP followed with laparoscopic cholecystectomy (LC). the patient divided into 2 equal group. in group 1, nasobiliary (NB) catheter was inserted during ERCP to settle high up in the intrahepatic biliary tree after complete CBD clearance. In group 2, only CBD clearance was done. In all patients LC was done within the same week of ERCP. sequential, multiple, step after step, tans-nasobiliary Intraoperative cholangiography was done during every step in cholecystectomy especially during dissection of calot's triangle and just before clipping of supposed cystic duct (CD) to make sure that the structure supposed to be CD was not the CBD. after the end of procedure methylene blue is injected from the the NB to detected any leak and if present

Inclusion Criteria:

• patients with GB stone complicated with CBD stones
• accept to share in the study
• the presence of one or more preoperative predictors for high risk for difficult cholecystectomy
• patient fit for LC

Exclusion Criteria:

• patients< 18 and >80
• unfit for surgery
• didn't accept to share in the study