Primary needle-knife fistulotomy for preventing post-endoscopic retrograde cholangiopancreatography pancreatitis: Importance of the endoscopist’s expertise level

Figure 1 Study flow chart. A: Experienced endoscopist; B: Less experienced endoscopist. ERCP: Endoscopic retrograde cholangiopancreatography; NKF: Needle-knife fistulotomy.

Figure 2 Comparison of precut sphincterotomy and needle-knife fistulotomy. A: Precut sphincterotomy. The needle is placed at the orifice of the ampulla; B: Precut sphincterotomy. Precutting was performed with slight upward tension; C: Needle knife fistulotomy. Mucosal incision at the maximal bulging point of the papillary roof of the ampulla; D: Needle knife fistulotomy. Incision at the oral side of the bile duct at the 11-12 o’clock position relative to the ampulla of Vater.

Figure 3 Ampulla configurations. A: Non-prominent; B: Bulging; C: Hook-shape, ampulla of Vater orifice was not shown due to huge bulging; D: Distorted.