Conversion of endoscopic nasobiliary drainage into internal drainage versus endoscopic biliary stenting for benign biliary obstruction: a retrospective propensity score-matched comparative study

Background: Endoscopic nasobiliary drainage (ENBD) conversion to internal drainage using scissor forceps is a specialized technique primarily explored in malignant obstructions. This study evaluates its efficacy, radiation safety, and long-term durability in patients with benign biliary obstruction (BBO) compared to conventional endoscopic retrograde biliary drainage (ERBD). Objectives: To evaluate the efficacy, radiation safety, and long-term durability of scissor forceps conversion compared to conventional endoscopic retrograde biliary drainage (ERBD) in patients with BBO. Design: A retrospective comparative study using 1:1 propensity score matching (PSM). Methods: We retrospectively analyzed BBO patients who underwent either scissor forceps conversion (Experimental group) or conventional ERBD (Control group) between 2018 and 2025. To ensure rigorous comparison, 1:1 propensity score matching (PSM) was performed, balancing baseline characteristics including age, etiology, and inflammatory markers. Primary endpoints were dose area product (DAP), fluoroscopy time, and long-term stent patency. Results: After 1:1 matching ( n = 43 per group), the experimental group demonstrated a significant reduction in radiation exposure and procedural duration. The mean DAP was substantially lower in the experimental group compared to the control group ( p < 0.001), alongside a shorter total fluoroscopy time ( p < 0.001). Although the early biochemical recovery showed a more favorable downward trend in total bilirubin for the experimental group, the difference was not statistically significant. Perioperative adverse events, including post-ERCP pancreatitis (4.65% vs 2.3%), were comparable, with all cases occurring prior to the conversion maneuver. During the follow-up, the experimental group exhibited a favorable trend toward sustained patency (Median Patency: Not Reached vs 13.0 months; p = 0.419). Conclusion: In BBO management, converting ENBD to internal drainage significantly enhances radiation safety and procedural efficiency without compromising clinical safety or long-term stent durability. This “mini-invasive” approach aligns with the ALARA principle and represents a refined evidence-based strategy for patients requiring cumulative biliary interventions.