Predictive variables for successful retrograde intrarenal surgery outcomes in pediatric patients: Development of...

Pediatric stone disease is characterized by its increasing prevalence and high recurrence rate. Consequently, the use of minimally invasive procedures with high stone-free rates (SFR) is essential. This study aims to identify risk factors associated with the failure of retrograde intrarenal surgery (RIRS) for renal stones smaller than 20 mm in pediatric patients and to develop predictive nomograms for preoperative patient selection. A retrospective analysis of 62 RIRS identified five key factors affecting SFR: stone volume, stone diameter, stone density, the presence of multiple stones, and lower calyx location. Among these variables, independent predictors of success were identified and incorporated into logistic regression models, which were subsequently translated into two nomograms. These represent the first tools specifically designed to predict preoperative SFR in pediatric patients undergoing RIRS. The predictive models developed in this study demonstrated high accuracy in predicting surgical success, providing urologists with reliable tools to individualize treatment planning based on preoperative imaging. Despite these promising results, external validation by high-volume pediatric urology centers is crucial to confirm the generalizability and robustness of these models. These findings represent a significant advancement in the personalized management of pediatric stone disease.