Side-Viewing Duodenoscope versus Forward-Viewing Gastroscope for Endoscopic Retrograde Cholangiopancreatography in Billroth II Gastrectomy Patients

Introduction: Endoscopic retrograde cholangiopancreatography (ERCP) in patients with Billroth II gastrectomy is still a challenging procedure. The optimal approach, namely the type of endoscope and sphincter management, has yet to be defined. Aim: To compare the efficacy and safety of forward-viewing gastroscope and the side-viewing duodenoscope in ERCP of patients with Billroth II gastrectomy. Methods: We conducted a retrospective, single-center cohort study of consecutive patients with Billroth II gastrectomy submitted to ERCP in an expert center for ERCP between 2005 and 2021. The outcomes assessed were: papilla identification, deep biliary cannulation, and adverse events (AEs). Multivariate analysis was performed to evaluate potential associations and predictors of the main outcomes. Results: We included 83 patients with a median age of 73 (IQR 65-81) years. ERCP was performed using side-viewing duodenoscope in 52 and forward-viewing gastroscope in 31 patients. Patients' characteristics were similar in the two groups. The global rate of papilla identification was 66% (n = 55). The rate of deep cannulation was 58% considering all patients and 87% in the subgroup of patients in which the papilla major was identified. Cannulation was performed with standard methods in 65% of cases and with needle-knife fistulotomy in 35%. AEs occurred in 4 patients. There was no difference between duodenoscope and gastroscope in papilla identification (64% [95% CI: 51-77] vs. 71% [55-87]). Although not statistically significant, duodenoscope had a lower deep cannulation rate when considering all patients (52% [15-39] vs. 68% [7-35]) and a higher AEs rate (8% [1-15] vs. 0% [0-1]). In a multivariate analysis, the use of gastroscope significantly increased the deep cannulation rate (OR = 152.62 [2.5-9,283.6]). Conclusion: This study demonstrates that forward-viewing gastroscope is at least as effective and safe as side-viewing duodenoscope for ERCP in patients with Billroth II gastrectomy. Moreover, our study showed that gastroscope is an independent predictor of successful cannulation.