Abstract

Objective: To analyze the morphology of kidney stones treated surgically by mini-percutaneous nephrolithotomy (mini-PCNL), and to evaluate the stone-free rate according to stone type and puncture site into the kidney after the first surgery with a single-tract mini-PCNL. Subjects and Methods: 86 patients underwent first-time percutaneous nephrolithotomy (PCNL) using a single-tract approach from January to December 2024 at Hue University of Medicine and Pharmacy Hospital. The patients underwent single-tract mini-PCNL in the lateral supine position, with puncture and dilation into the kidney under ultrasound and C-arm guidance. Stones were classified according to the Guy’s Stone Score (GSS). The selection of puncture site was based on GSS, degree of hydronephrosis, and puncture direction to access the stone. Patients were re-evaluated one month postoperatively. The stone-free rate is assessed in relation to the puncture site, punctured calyx, GSS, and a combination of them. Complications were classified according to the Clavien-Dindo classification. Results: The distribution of stones according to Guy’s Stone Score I, II, III, and IV was 25.6%, 15.1%, 25.6%, 40 TẠP CHÍ Y DƯỢC HUẾ - HUE JOURNAL OF MEDICINE AND PHARMACY ISSN 3030-4318; eISSN: 3030-4326 and 33.7%, respectively. Successful puncture and dilation of the tract into the kidney were achieved in 100% of cases on the first attempt, the average time of this procedure was 4,2 ± 0,3 minutes. The puncture sites were: upper calyx (52.3%), middle calyx (32.6%), and lower calyx (15.1%). Stone-free rates after the first surgery with one tract were: upper calyx 82.2%, middle calyx 89.3%, and lower calyx 84.6%. Stone-free rates according to Guy’s Stone Score I, II, III, and IV were 100.0%, 92.3%, 81.8%, and 72.4%, respectively. There was no statistically significant difference in stone-free rate among the puncture sites (p > 0.05), but a significant difference was observed across GSS groups (p < 0.05). Conclusion: Complex stones (GSS III and IV) accounted for more than half of the surgical cases. While the stone-free rate did not significantly differ by puncture site, it did vary significantly by Guy’s Stone Score classification.