Acute distal common bile duct angle is risk factor for post-endoscopic retrograde cholangiopancreatography pancreatitis in beginner endoscopist

Figure 1 Example of an acute and obtuse distal common bile duct angle. A: An acute distal common bile duct (CBD) angle; B: The measurement of acute distal CBD angle; C: An obtuse distal CBD angle; D: Measurement of obtuse distal CBD angle.

Figure 2 Schematic diagram of cannulation. A: Difficulty of cannulation for an acute distal common bile duct angle; B: Upward manipulation of the catheter may decrease the difficulty of the bile duct cannulation.