Efficacy of Pancreatoscopy for Pancreatic Duct Stones: A Systematic Review and Meta-Analysis

Background Pancreatic duct stones can lead to significant abdominal pain for patients. Per oral pancreatoscopy (POP)-guided intracorporal lithotripsy is being increasingly used for the management of main pancreatic duct calculi (PDC) in chronic pancreatitis. POP uses two techniques: Electrohydraulic lithotripsy (EHL) and laser lithotripsy (LL). Data on the safety and efficacy are limited for this procedure. We performed a systematic review and meta-analysis with a primary aim to calculate the pooled technical and clinical success rates of POP. The secondary aim was to assess pooled rates of technical success, clinical success for the two individual techniques, and adverse event rates. Aim To perform a systematic review and meta-analysis of POP, EHL and LL for management of PDC in chronic pancreatitis. Methods We conducted a comprehensive search of multiple electronic databases and conference proceedings including PubMed, EMBASE, Cochrane, Google Scholar and Web of Science databases (from 1999 to October 2019) to identify studies with patient age greater than 17 and any gender that reported on outcomes of POP, EHL and LL. The primary outcome assessed involved the pooled technical success and clinical success rate of POP. The secondary outcome included the pooled technical success and clinical success rate for EHL and LL. We also assessed the pooled rate of adverse events for POP, EHL and LL including a subgroup analysis for the rate of adverse event subtypes for POP: Hemorrhage, post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), perforation, abdominal pain, fever and infections. Technical success was defined as the rate of clearing pancreatic duct stones and clinical success as the improvement in pain. Random-effects model was used for analysis. Heterogeneity between study-specific estimates was calculated using the Cochran Q statistical test and I 2 statistics. Publication bias was ascertained, qualitatively by visual inspection of funnel plot and quantitatively by the Egger test. Results A total of 16 studies including 383 patients met the inclusion criteria. The technical success rate of POP was 76.4% (95%CI: 65.9-84.5; I 2 = 64%) and clinical success rate was 76.8% (95%CI: 65.2-85.4; I 2 = 66%). The technical success rate of EHL was 70.3% (95%CI: 57.8-80.3; I 2 = 36%) and clinical success rate of EHL was 66.5% (95%CI: 55.2-76.2; I 2 = 19%). The technical success rate of LL was 89.3% (95%CI: 70.5-96.7; I 2 = 70%) and clinical success rate of LL was 88.2% (95%CI: 66.4-96.6; I 2 = 77%). The incidence of pooled adverse events for POP was 14.9% (95%CI: 9.2-23.2; I 2 = 49%), for EHL was 11.2% (95%CI: 5.9-20.3; I 2 = 15%) and for LL was 13.1% (95%CI: 6.3-25.4; I 2 = 31%). Subgroup analysis of adverse events showed rates of PEP at 7% (95%CI: 3.5-13.6; I 2 = 38%), fever at 3.7% (95%CI: 2-6.9; I 2 = 0), abdominal pain at 4.7% (95%CI: 2.7-7.8; I 2 = 0), perforation at 4.3% (95%CI: 2.1-8.4; I 2 = 0), hemorrhage at 3.4% (95%CI: 1.7-6.6; I 2 = 0) and no mortality. There was evidence of publication bias based on funnel plot analysis and Egger's test. Conclusion Our study highlights the high technical and clinical success rates for POP, EHL and LL. POP-guided lithotripsy could be a viable option for management of chronic pancreatitis with PDC.