Rescue cannulation techniques in difficult biliary access-A comprehensive review

Selective biliary cannulation is the prerequisite for successful biliary interventions. In the setting of cannulation failure, various rescue cannulation techniques are used for achieving selective biliary access. The various rescue cannulation techniques are (1) free-hand techniques (precut papillotomy and fistulotomy); (2) wire-guided techniques (transpancreatic sphincterotomy [TPS] and double guidewire [DGW]) and (3) endoscopic ultrasound (EUS)-guided technique (EUS-guided rendezvous for biliary access). The morphology of the papilla is the best guide to select the rescue technique. For classic and pendulous down facing papilla, pre-cut fistulotomy is preferable while for irregular ridged type, pre-cut papillotomy is suitable, while for small flat type, a very cautious pre-cut papillotomy may be utilized only by experts in pre-cut techniques. When an inadvertent pancreatic duct cannulation occurs, TPS is the preferred technique for all except small flat type of papilla where DGW is preferable to avoid perforation. We review the literature comparing these techniques to assess their efficacy and safety. Finally, we provide an algorithm that can be used to select the best rescue technique.