Predicting the Success of Flexible Ureterorenoscopy for Kidney and Upper Ureter Stones

This observational study aims to test how well a specific medical scoring tool, called a nomogram, can predict the success of a common minimally invasive surgery for kidney stones. The surgery being studied is flexible ureterorenoscopy (fURS), which is widely used to treat stones in the kidney and the upper part of the ureter. In this study, procedural success is defined as a patient being completely stone-free after their surgery. While fURS is highly effective, the chances of completely clearing all stones can vary from person to person based on individual factors like stone size, stone volume, and anatomical characteristics. Researchers want to determine if this nomogram can accurately estimate a patient's personalized chance of achieving a stone-free outcome before the intervention takes place. Participants in this study will be adult patients who are already scheduled to undergo fURS as part of their standard medical care. Because this is an observational study, there are no experimental treatments, participants will receive their normal surgical care. During the study, the research team will collect standard clinical information, including: * Preoperative data such as age, body mass index (BMI), blood tests, and CT scan results. * Operative details during the surgery, such as the time it takes, the experience level of the surgeon, and the laser settings used to break up the stones. * Postoperative outcomes, specifically reviewing follow-up imaging to check for the presence and size of any remaining stone fragments. By comparing the nomogram's preoperative predictions to the patients' actual surgical results, the researchers hope to validate the tool's accuracy. Confirming the reliability of this tool could help doctors better plan individualized treatments, avoid unnecessary procedures, and improve how they counsel future patients regarding their expected surgical outcomes.