Single-use versus reusable flexible ureterorenoscopes with FANS: a multicenter propensity-matched analysis of outcomes in a large series from the EAU-Endourology Section and FANS Collaborative Group

Abstract

Objective: This study compares the clinical outcomes of single-use and reusable flexible ureterorenoscopes (fURS) in retrograde intrarenal surgery (RIRS) with flexible and navigable suction access sheath (FANS).

Methods: A multicenter prospective analysis included 704 patients who underwent RIRS with FANS between July 2023 and March 2024. Patients were stratified into two groups: those treated with single-use fURS (Group 1, n = 263) and those with reusable fURS (Group 2, n = 441). Propensity score matching (PSM) was used to reduce confounding in the statistical comparisons. The primary outcomes were stone-free rate (SFR) and complication rates, assessed through pre- and postoperative non-contrast computed tomography (NCCT) scans. Statistical analyses were performed using R software, with p < 0.05 considered significant.

Results: After propensity score matching, 226 patients per group were well-balanced across baseline characteristics (ASMD < 0.1). Group 1 was associated with shorter laser (p = 0.001) and operative times (p = 0.048), and more frequent use of larger sheaths (p < 0.001). Complication rates were low and comparable between groups. Group 1 achieved higher 100% stone free status (65.5% vs. 55.8%, p = 0.012), though overall stone-free rates were similar. Reintervention rates did not differ significantly. Lasing and exit strategy did not differ between the two groups. On multivariate analysis, single-use scope use (OR 1.659, p = 0.018) and 10-12 Fr UAS (OR 1.749, p = 0.043) were significantly associated with complete stone clearance.

Conclusion: Our study findings indicate that FANS is a safe and effective technique irrespective of the type of scope used. However, as FANS offers the potential to achieve a truly 100% stone-free status, this outcome is more likely when using single-use scopes in combination with 10/12 sheaths. Given that stone volume is a significant determinant of stone-free outcomes, surgeons may consider selecting the scope type to tailor the procedure according to stone complexity.

Keywords: Flexible and navigable suction access sheaths; Flexible ureterorenoscopes; Reusable; Single-use; Stone-free rate.