Abstract: Objective To explore if the angle of distal common bile duct is the risk factors for PEP in beginner endoscopists without supervision.
Methods We studied a retrospective analysis of 65 patients who were perfomed ERCP from the beginner endoscopists,Patients were Classified as acute(angle≤30°)and obtuse(angle＞30°).The angle of the distal common bile duct(CBD) was measured as the angle between the lower wall of the bile duct and a vertical line on coronal view CT.Time of cannulation,The rate of pancreatic duct cannulation,Hyperamylasemia and PEP were compared between two groups.
Results ERCP success rate was 91.1 % in the acute angle group and 96.8% in the obtuse group.The cannulation time was angle group(10.05±2.67)min vs(9.35±2.79)min.The ratio of pancreatic duct cannulation was acute 50% than obtuse 32.2% angle group,Hyperamylasemia was acute 20.6%,obtuse 19.4%.The rate of PEP was acute(26.5%) than obtuse(3.22%) angle group(P = 0.018).No other severe complications(bleeding and perforation) were happened(P＜0.05).
Conclusion Obtuse distal CBD angle may have lower risk of PEP when beginner endoscopists performing ERCP.

Key words: endoscopic retrograde pancreatic cholangiopancreatography, beginner endoscopists, post ercp pancreatitis