Introduction: Single-use (SU) ureteroscopes offer cost-effective advantages over traditional reusable devices in clinical settings with increased risk of device damage. One technical drawback of SU scopes is decreased brightness and clarity of the visual field, which may impair case completion. The Karl Storz FLEX-XC1 is a novel single-use flexible ureteroscope that uses the same video graphics platform as its reusable digital counterpart. We aimed to evaluate the technical performance of the XC1 in initial clinical use. Methods: We reviewed a series of consecutive ureteroscopy procedures performed by 2 endourologists. We used the XC1 for indications in which we typically use a single-use device: stone burden >15 mm overall or >10 mm in the lower pole; expected case duration >60 min; bilateral procedure; distorted anatomy. For each case, we assessed pre-case tip deflection, intraoperative mechanical failure, and clinical outcomes. Surgeons rated visual clarity, image quality, and mechanical handling on a 1 to 5 Likert scale. Results: A total of 21 procedures were attempted using XC1, and 20 (95%) were completed successfully. Pre-case incomplete deflection was noted in 7 (33%) cases: pre-case upward deflection was <270° in 4 (19%) cases (range 200-250°), and downward deflection was <270° in 5 (24%) cases (range 180-250°). Pre-case incomplete deflection did not preclude completion of any case. Three intraoperative malfunctions occurred: rotational twisting of the deflectable distal tip (2 cases, 10%) and inability to pass a 365-micron laser fiber fully through the working channel (1 case, 5%), requiring conversion to another device. Visual clarity, image quality, and mechanical handling were rated as 4 (very good) or 5 (excellent) in 100%, 100%, and 76% of cases. Fig 1 shows representative image quality between the reusable digital Storz FLEX-XC, SU Storz FLEX-XC1, and SU Dornier AXIS. No device-specific or general 30-day complications were observed. Conclusions: In this pilot trial of the FLEX-XC1, visual clarity and image quality were subjectively similar to reusable digital devices and rated highly by operators. We observed incomplete deflection in 33% of cases and mechanical failure in 1 case. XC1 may be advantageous in prolonged cases where maintaining visual clarity is paramount. SOURCE OF Funding: None
