This study aimed to initially investigate the feasibility of robotic retrograde intrarenal surgery(RIRS) in a pilot porcine model study using a second version of robotic flexible ureteroscopy system, ZamenixTMP.

The second version of the robotic flexible ureteroscopy system, ZamenixTMP was used, featuring enhanced control precision, respiratory synchronization, stone size guidance, automated driving, and ureteral access sheath (UAS) position adjustment with haptic feedback. Seven female farm pigs weighing 41-50 kg were used for a comparative study evaluating the feasibility of robotic RIRS compared with manual RIRS. A total of 12 cases (six manual RIRS and six robotic RIRS) were performed by three urologists with varying levels of manual RIRS experience. For each case, an artificial stone (BegoStone Plus, BEGO USA, US) measuring 3.2 mm in diameter and 15 mm in length was inserted to the kidney through an 11/13 Fr ureteral access sheath.

The newly updated functions, including respiratory synchronization, stone size guidance, automated driving and UAS position adjustment with haptic feedback were feasible and operated without safety issues in vivo. Stone-free status was achieved in all cases across both groups. Stone treatment times were 38.5 minutes (29.8-45.8) in manual RIRS and 40.5 minutes (33.0-45.0) in robotic RIRS, with no significant difference (p=0.818). The occurrence of laser injury was 3.5 (2.3–4.0) in manual RIRS and 1.5 (1.0-2.0) in robotic RIRS, without significant difference (p=0.123). The occurrence of stone impaction during retrieval was 0.5(0.0-1.0) in manual RIRS and 0.0(0.0-0.0) in robotic RIRS, with no significant difference (p=0.545). Other endpoints, including stone fragmentation time, stone retrieval time, occurrence of hematuria, and ureteral injury were comparable in both groups showing no statistical significance. Overall ease-of-use scores were comparable, with robotic RIRS showing favorable scores for ease of stone fragmentation and the ability to recognize stone size during retrieval.

These initial in vivo experimental results demonstrated the feasibility and safety of robotic RIRS using the second version of ZamenixTMP. Despite limited experience with robotic RIRS, all participants completed the procedure with comparable efficacy and safety to manual RIRS. Further studies are required to optimize the robotic RIRS techniques and to validate its efficacy.