The Role of Preoperative Ureteral Diameter Measurements in Predicting Difficult Access During Retrograde Intrarenal Surgery: A Retrospective Analysis of 234 Patients

This retrospective study evaluates the role of preoperative ureteral diameter measurements in predicting difficult access during retrograde intrarenal surgery (RIRS) in patients with kidney stones. A total of 234 patients who underwent RIRS were included in the analysis. Preoperative computed tomography (CT) scans were used to measure ureteral diameters at three levels: distal ureter, iliac ureter, and upper ureter. The relationship between ureteral diameter and intraoperative access difficulty was assessed.

The study also analyzed patient demographics (age, gender, BMI), stone characteristics (size, location), operative parameters (duration, access attempts), and outcomes (surgical success and complication rates). Difficult access during RIRS was defined based on the number of attempts required to achieve successful ureteral access, need for secondary procedures, or inability to complete the planned surgery.

The primary aim was to determine whether preoperative ureteral diameter measurements can serve as predictive markers for challenging surgical access. Secondary objectives included identifying other patient or stone-related factors contributing to access difficulty and evaluating their impact on surgical outcomes. The findings may assist clinicians in preoperative planning, improving patient selection for RIRS, and optimizing intraoperative strategies to minimize complications and enhance procedural success rates.

Inclusion criteria

Patients aged 18 years or older. Diagnosed with kidney stones (nephrolithiasis) requiring surgical intervention. Underwent retrograde intrarenal surgery (RIRS). Available preoperative CT scans for ureteral diameter measurements. Complete medical records, including demographic, clinical, and surgical data.

Exclusion criteria

History of open or laparoscopic renal surgery. Presence of ureteral strictures or congenital anomalies. Patients with incomplete or missing medical records. Active urinary tract infection at the time of surgery. Pregnant or lactating individuals.