Favorable impact of a novel endoscopic auxiliary system (NEAS) on fluoroscopy-guided lithotripsy for difficult bile duct stones: A pilot study

Objectives: Laser lithotripsy under fluoroscopic guidance is difficult to perform and risky due to its invisibility. In this study we aimed to investigate the efficacy and safety of a novel endoscopic auxiliary system (NEAS)-assisted lithotripsy under fluoroscopy for treating difficult common bile duct (CBD) stones.Methods: Patients with difficult CBD stones who were treated with NEAS-assisted laser lithotripsy (NEAS group) or conventional mechanical lithotripsy (ML) under fluoroscopy (ML group) were retrospectively evaluated. The primary outcome was the complete stone clearance rate and the secondary outcomes included operation time, complications, and medical cost.Results: Seventeen patients were treated with NEAS-assisted laser lithotripsy and 144 patients underwent ML. Using the propensity score matching analysis, 17 pairs of cases treated with NEAS-assisted lithotripsy and ML were included. Patients in the NEAS group showed a higher stone clearance rate than the ML group (94.1% vs 58.8%, P = 0.039), as well as shorter operation time (41.9 min vs 49.4 min, P < 0.001) and lower medical cost (USD 4607 vs USD 5014, P < 0.001). There was no significant difference in the complication rate between the two groups (5.9% vs 17.6%, P = 0.601).Conclusion: NEAS-assisted fluoroscopy-guided laser lithotripsy is feasible and safe, which may be a promising technique in fluoroscopy-guided laser lithotripsy for difficult CBD stones.