To compare the efficacy and safety of cap-fitted forward-viewing endoscopy versus side-viewing duodenoscopy for ERCP in patients with prior Billroth II gastrectomy.

A systematic-review of PubMed, Scopus, Embase and Cochrane Library was performed to include randomized trials and observational studies evaluating ERCP in Billroth II anatomy comparing cap-fitted forward-viewing endoscopes with duodenoscopes. data extraction. The restricted estimation likelihood random-effects was applied to pool studies effects as risk ratios (RR). Statistical significance was considered as p < 0.05. Outcomes were pooled using both patients and procedures as the units of analysis whenever data allowed.

Seven studies met the inclusion criteria, comprising 433 patients and 516 ERCP procedures. Across all efficacy outcomes, no statistically significant differences were identified between cap-fitted forward-viewing endoscopy and side-viewing duodenoscopy. Afferent limb intubation rates were virtually identical (RR 1.00; 95% CI 0.97–1.04), and cannulation success likewise showed similar performance between techniques (RR 0.96; 95% CI 0.80–1.10). Clinical success rates were also comparable (RR 1.02; 95% CI 0.87–1.20).

Safety outcomes demonstrated comparable overall adverse event profiles between groups. However, relevant non-significant trends were consistently observed. Forward-viewing endoscopy with cap showed a trend toward higher post-ERCP pancreatitis (RR 2.23; 95% CI 0.66–7.54). Conversely, a trend toward lower perforation rates was noted with cap use (RR 0.52; 95% CI 0.09–3.08), in line with reports suggesting that cap-assisted techniques may provide improved visualization and safer advancement in altered anatomy. All pooled analyses exhibited minimal heterogeneity (I² = 0%), reinforcing the consistency of results across studies.

This is the first meta-analysis to directly compare cap-fitted forward-viewing endoscopy and side-viewing duodenoscopy for ERCP in patients with Billroth II gastrectomy. Our findings demonstrate that both techniques offer comparable overall efficacy and safety. Although no statistically significant differences were identified, consistent trends were observed: the cap-fitted approach showed a tendency toward higher rates of post-ERCP pancreatitis, whereas perforation appeared to be less frequent. These results highlight a more nuanced risk–benefit profile that may support individualized technique selection based on patient anatomy, procedural objectives, and operator expertise. The consistent directionality of these trends reinforces the need for high-quality prospective studies to clarify true risk differences and refine endoscope selection algorithms in altered anatomy.