Utility of needle-knife fistulotomy as an initial method of biliary cannulation to prevent post-ERCP pancreatitis in a highly selected at-risk group: a single-arm prospective feasibility study

The aim of this study was to assess the feasibility of needle-knife fistulotomy (NKF) as an initial procedure for biliary access in patients with stones in the common bile duct (CBD) who were at increased risk for post-ERCP pancreatitis (PEP).Fifty-five patients who underwent ERCP with NKF for CBD stones at our institution between July 2013, and May 2015, were prospectively enrolled in this study. They had one or more of the following risk factors for PEP: young age (60 years), female sex, or normal CBD diameter (≤9 mm). The procedure was performed by an expert biliary endoscopist (S.J.). The success rate of biliary cannulation and CBD stone removal, and the incidence rate of adverse events were assessed.Seventeen patients had 1 risk factor for PEP, 27 had 2, and 11 had 3. The median procedure times for NKF and CBD stone removal after NKF were 2.1 minutes (range, 0.2-8.7 min) and 6.5 minutes (range, 1.1-28.3 min), respectively. Success rates of CBD cannulation and stone removal using NKF were 96.3% (53/55) and 92.7% (51/55), respectively. None of the patients experienced PEP. Retroperitoneal duodenal perforation occurred in 1 patient (1.8%), but it was successfully treated by conservative management.NKF might be feasible as an initial procedure for biliary access in patients with CBD stones who are at high risk for PEP if the procedure is performed by an expert biliary endoscopist. (Clinical trial registration number: KCT0001698.).