Low- versus high-power holmium: YAG laser strategies affect operative efficiency in suction-assisted mini-PCNL in a randomized controlled trial

To compare operative efficiency and perioperative outcomes between low-power (LP) and high-power (HP) holmium: yttrium aluminum-garnet (Ho: YAG) laser strategies in suction-assisted mini-percutaneous nephrolithotomy (mini-PCNL), we conducted a prospective randomized controlled trial including 100 adult patients with renal calculi randomized 1:1 to LP (n = 50) or HP (n = 50) settings. All procedures were performed using suction-assisted mini-PCNL. The primary outcome was total operative time, with secondary outcomes including laser activation time, total laser energy, energy density, ablation speed, stone-free rate (SFR) at 6 weeks, and complications. Baseline characteristics were comparable between groups. The HP group demonstrated significantly shorter operative time (90.7 ± 18.7 vs. 112.1 ± 40.3 min; P = 0.001) and laser activation time (1893 ± 499 vs. 2548 ± 1001 s; P = 0.001). Although total energy delivery was higher in the HP group (37.6 vs. 25.1 kJ; P = 0.001), ablation speed was significantly greater (1.6 vs. 1.2 mm³/s; P = 0.002), while the LP group showed greater energy efficiency (10.9 vs. 16.4 J/mm³; P = 0.002). Six-week SFR (86.0% vs. 88.0%; P = 0.766), complication rates, and hospital stay were comparable. Within a suction-assisted mini-PCNL setting, HP Ho: YAG laser strategies were associated with improved operative efficiency, primarily reflected by shorter operative and lasing times, at the expense of lower energy efficiency, without differences in short-term clinical outcomes. These findings should be interpreted as reflecting differences in clinically applied laser strategies rather than isolated laser power effects.