Performance of different approaches to difficult biliary cannulation in endoscopic retrograde cholangiopancreatography: A systematic review and network meta-analysis

Background: It is unclear which is the best strategy for difficult biliary cannulation in endoscopic retrograde cholangiopancreatography (ERCP). Aims: We compared the different techniques, through a network meta-analysis combining direct and indirect comparisons. Methods: We identified 12 randomized controlled trials (1605 patients) comparing different techniques for difficult biliary cannulation (early and late needle knife techniques, pancreatic guidewire- and stent-assisted techniques, transpancreatic sphincterotomy, and endoscopic ultrasound rendez-vous [EUS-RV]) either with each other or with persistence with the standard cannulation techniques. The success rate of biliary cannulation and the incidence of post-ERCP pancreatitis (PEP) were the primary outcomes. Results: Only transpancreatic sphincterotomy significantly outperformed pancreatic stent assisted cannulation (risk ratio [RR] 1.33, 1.00-1.55), whereas no difference was observed among the other techniques in terms of cannulation success. SUCRA ranking suggested EUS-RV and early needle knife techniques as the best performing approaches (SUCRA 0.78 and 0.68, respectively). In terms of PEP rate, only EUS-RV significantly outperformed pancreatic guidewire-assisted techniques (RR 0.21, 0.04-0.98). Conclusions: Based on low quality of evidence, the several techniques for difficult biliary cannulation show similar results although a trend in favour of needle knife techniques and EUS-RV was observed. EUS-RV seems to decrease the risk of PEP.