Morphology of the papilla can predict procedural safety and efficacy of ERCP—a systematic review and meta-analysis

Endoscopic Retrograde Cholangiopancreatography (ERCP) is the primary therapeutic procedure for pancreaticobiliary disorders, and studies highlighted the impact of papilla anatomy on its efficacy and safety. Our objective was to quantify the influence of papilla morphology on ERCP outcomes. We systematically searched three medical databases in September 2022, focusing on studies detailing the cannulation process or the rate of adverse events in the context of papilla morphology. The Haraldsson classification served as the primary system for papilla morphology, and a pooled event rate with a 95% confidence interval was calculated as the effect size measure. Out of 17 eligible studies, 14 were included in the quantitative synthesis. In studies using the Haraldsson classification, the rate of difficult cannulation was the lowest in type I papilla (26%), while the highest one was observed in the case of type IV papilla (41%). For post-ERCP pancreatitis, the event rate was the highest in type II papilla (11%) and the lowest in type I and III papilla (6–6%). No significant difference was observed in the cannulation failure and post-ERCP bleeding event rates between the papilla types. In conclusion, certain papilla morphologies are associated with a higher rate of difficult cannulation and post-ERCP pancreatitis.