Compare the Knob-tipped Knife With the Needle Knife in Difficult Biliary Cannulation

• Successful biliary cannulation rate after precut papillotomy [ Time Frame: During endoscopic retrograde cholangiopancreatography (ERCP) procedure ] [ Designated as safety issue: No ]
  

• Biliary cannulation time after precut papillotomy [ Time Frame: From precut papillotomy started to biliary cannulation achieved or abandoned ] [ Designated as safety issue: No ]
  

• The incidence of Early complications of endoscopic retrograde cholangiopancreatography(ERCP) including pancreatitis, hemorrhage, and perforation [ Time Frame: 7 days after ERCP ] [ Designated as safety issue: Yes ]
  

Precut sphincterotomy is an alternative technique used to facilitate CBD cannulation following the failure of conventional bile duct cannulation. Needle knife papillotomy is the most widely practiced precut technique. However,Pre-cutting the papilla with a needle-knife is difficult, requiring experience and dexterity to control the axis and depth of the cut. Due to the increased rate of complications associated with this procedure, including pancreatitis, hemorrhage, and perforation, it was recommended to be performed only by experienced endoscopists.

The knob-tipped knife, a novel instrument utilizing a 2mm or 1.5mm cutting knife, is usually used for endoscopic submucosal dissection (ESD). Its knob-shaped tip and nonadjustable length make the knife less likely to slip and penetrate the tissue during the resection. Since the process of precut papillotomy is similar to ESD, the precutting procedure with the knob-tipped knife may be easier to be performed, as well as be safer. The efficacy and safety of this instrument in precut papillotomy have not been reported. We therefore assessed the efficacy and safety of the knob-tipped knife in precut papillotomy in difficult CBD cannulation.