Is 3 cm the upper limit of stone size for effective steerable ureteroscopic renal stone evacuation?

PURPOSE: The CVAC® Aspiration System is a novel device designed to actively evacuate stone fragments during ureteroscopy. While recent studies have validated its safety, the precise upper limit of stone size for this treatment is undefined. We aimed to determine the ideal size and volume thresholds using CVAC for steerable ureteroscopic renal evacuation (SURE) procedures. METHODS: A retrospective, observational study of patients undergoing SURE procedures by a single surgeon between August 2023 and April 2025 was undertaken. Stone size and volume were quantified using preoperative CT imaging. The primary outcome was stone-free status, based on Endourological Society criteria for CT, or