A prospective, observational study to evaluate the efficacy of the retrograde intrarenal surgery scoring system for predicting stone-free rate following retrograde intrarenal surgery

ABSTRACT Introduction: Retrograde intrarenal surgery (RIRS) is widely performed for renal calculi; however, stone-free outcomes vary according to the stone burden and intrarenal anatomy. The RIRS scoring system was developed to objectively predict the stone-free rate (SFR) using preoperative computed tomography (CT) parameters. This study prospectively evaluated its predictive performance.