Comparative Analysis of RIRS Scoring System and Resorlu Unsal Stone Score (RUSS) for Predicting Stone-free Rate After Retrograde Intrarenal Surgery

The intervention involves Retrograde Intrarenal Surgery (RIRS) performed using a flexible ureteroscope to access the renal collecting system via a retrograde (urethra → bladder → ureter → kidney) approach. Stones are fragmented using a holmium:YAG laser, with or without the use of a ureteral access sheath, depending on the case. What distinguishes this intervention from others is the integration of preoperative scoring systems-specifically the RIRS Scoring System and the Resorlu Unsal Stone Score (RUSS)-to predict stone-free outcomes and guide case selection and surgical planning. Additionally, all procedures are performed by experienced endourologists following a standardized protocol, including consistent patient positioning, anesthesia, access technique, and post-operative imaging at defined intervals to assess outcomes.