Comparison of clinical effectiveness and safety of 272 µm and 365 µm holmium lasers in retrograde intrarenal surgery

Abstract

Introduction: Surgeons typically prefer 270 µm and 272 µm laser probes in retrograde intrarenal surgery (RIRS) due to the reduced deflection capacity of flexible ureterorenoscopes when using larger probe diameters. This study aims to investigate the effects of 272 and 365 µm holmium laser probes on operative time, clinical efficacy, and complication rates in RIRS.

Materials and methods: A total of 285 patients with proximal ureteral or kidney stones who met the inclusion criteria were enrolled in the study. Patients were divided into two groups based on laser probe thickness: 272 µm and 365 µm. Stone-free rates, operative time, and complication rates were compared between the groups. Factors affecting stone-free rates were analyzed using multivariate logistic regression analysis.

Results: Patient and stone characteristics were similar between the two groups. No significant differences were found in stone-free or complication rates. However, operative time was significantly shorter in the 365 µm probe group. In univariate analysis, risk factors for postoperative residual stones included multi-calyceal stones, lower pole stones, high Hounsfield unit (HU) values on non-contrast computed tomography, and larger stone size. In multivariate analysis, independent prognostic factors for residual stones were identified as multi-calycal stones, lower pole stones, and high HU values.

Conclusion: Compared to 272 µm laser probes, operative time was shorter in surgeries performed with 365 µm laser probes. The 365 µm holmium laser can be effectively and safely used in the treatment of proximal ureteral and renal stones, demonstrating high clinical efficacy and safety.

Keywords: 272 µm laser; 365 µm laser; RIRS; effectiveness; safety.