Ersin GÖKMEN, Türker ALTUNTAŞ, Halil Batur AKAY, Günal ÖZGÜR, Yusuf ŞENOĞLU, Çağrı Akın ŞEKERCİ, Tarık Emre ŞENER
The New Journal of Urology - 2026;21(2):72-80
Objective: To evaluate the predictive value of volumetric stone measurements including manually calculated stone volume and 3D software-derived volume on stone-free outcomes following mini-percutaneous nephrolithotomy (mini-PCNL), and to assess their relationship with perioperative parameters and commonly used nephrolithometry scoring systems. Materials amd Methods: This retrospective study was conducted with patients who underwent primary mini-PCNL between January 2024 and January 2025. Preoperative non-contrast computed tomography scans were used to determine the longest stone diameter, surface area, manually calculated stone volume, and 3D software-derived stone volume. Patients were categorized into two groups according to postoperative imaging: stone-free (Group 1) and residual stone (Group 2). Demographic characteristics, stone features, operative parameters, stone complexity scores (GUY's and STONE) and complication rates were compared between groups. Results: Of the 80 patients, 61.3% were stone-free postoperatively. Group 2 demonstrated significantly higher manually calculated stone volumes (p = 0.02) and S.T.O.N.E. scores (p = 0.005). Manually calculated and 3D-derived stone volumes both showed significant positive correlations with stone diameter, surface area, nephrolithometry scores, operative time, and laser usage parameters. ROC analysis identified a manually calculated stone volume threshold of 746.9 mm³ for predicting residual fragments (AUC = 0.656, p = 0.02). In the multivariate model, manual stone volume was significantly associated with stone-free status (OR 18.71, p = 0.042). Conclusion: This study demonstrates a significant association between stone volume and stone-free outcomes after mini-PCNL. While volumetric measurements may provide additional information beyond conventional parameters. Therefore, stone volume should be considered as a complementary parameter rather than a standalone predictor in clinical decision-making.
