Difficult biliary cannulation during ERCP: how to facilitate biliary access and minimize the risk of post-ERCP pancreatitis

Endoscopic retrograde cholangio-pancreatography (ERCP) is one of the most technically challenging procedures in therapeutic endoscopy; difficulties in biliary cannulation and post-ERCP pancreatitis are still significant problems. Deep cannulation of Vater's papilla may fail in up to 5% of cases; selective biliary cannulation reportedly fails in 15-35% of cases, even in experienced hands; repeated and prolonged attempts at cannulation increase the risk of post-procedure pancreatitis. Therefore, cannulation technique plays a pivotal role in successful cannulation and occurrence of post-procedure pancreatitis. This review presents and discusses the techniques that can be used for achieving biliary cannulation after an initial failure and for minimizing the risk of pancreatitis, including guide wire assisted technique, needle knife precutting, trans-pancreatic sphincterotomy, and pancreatic stenting.