High-Power Retrograde Intrarenal Surgery Holmium Laser Lithotripsy for Kidney Stones Larger Than 20 mm

Percutaneous nephrolithotomy (PCNL) is the gold standard for treating kidney stones >20 mm because of its superior stone-free rates (SFR). However, high-power holmium lasers may challenge this standard. This study evaluates the feasibility, safety, and efficacy of high-power holmium laser retrograde intrarenal surgery (RIRS) for the treatment of kidney stones >20 mm.

We conducted a retrospective analysis of patients with kidney stones >20 mm treated with either 80W- or 120 W holmium laser RIRS between January 2020 and August 2024. Clinical, intraoperative, and postoperative data were collected. Outcomes included SFR, operative time, complications, and hospital stay. Comparisons between the older-generation (80 W) and newer-generation (120 W) systems were performed using the Mann-Whitney U test and chi-square test, and multivariable analyses identified predictors of non-stone-free status.

A total of 118 patients were included: 31 in the older-generation (80 W) group and 87 in the newer-generation (120 W) group. RIRS using the newer-generation 120 W laser was associated with a shorter operative time (66 vs 79 minutes, p < 0.001) and higher SFR at 5 weeks (82.7% vs 58.1%, p = 0.006), 6 months (92% vs 64.5%, p < 0.001), and 1 year (96.5% vs 83.8%, p = 0.016) postoperative evaluations. Complication rates did not differ significantly between groups (5.7% vs 3.2%, p = 0.208). In multivariable analysis, the use of older-generation 80 W laser was an independent predictor of non-stone-free status at both the first (OR 4.4, p = 0.004) and second (OR 8.8, p = 0.001) follow-up visits.

Treatment of renal stones larger than 2 cm with the newer-generation 120 W Ho:YAG laser is effective, with higher SFR rate and shorter operative time, compared to the older-generation 80 W Ho:YAG laser.