Could the High-Power Laser Increase the Efficacy of Stone Lithotripsy During Retrograde Intrarenal Surgery?

Abstract

Objective: To compare a high-power setting in holmium: yttrium-aluminum-garnet laser lithotripsy with the established low-power setting approach during retrograde intrarenal surgery (RIRS). Materials and Methods: Our study analyzed the data of consecutive patients managed with RIRS. The patients were divided into two groups according to the employed laser settings of power, energy, and frequency; dusting (20 W = 0.5 J × 40 Hz) (group 1) and stone self-popping (60 W = 1.5-2 J × 30-40 Hz) (group 2). Perioperative outcomes, including operative time (OT) and stone disintegration time (SDT), were compared between groups. The stone-free rate (SFR) was evaluated 1 month after the surgery. Results: Overall, 174 patients with 179 renal units were included. The dusting mode was utilized in 98 patients (100 renal units), whereas 76 patients (79 renal units) underwent the stone self-popping technique. The SFR was 82.1% for both groups. The OT and SDT were 60.1 ± 18.6 and 32.6 ± 9.4 minutes, respectively, for group 1 and 44.9 ± 15.5 and 16.5 ± 4.7 minutes, respectively, for group 2. According to the final analysis, laser lithotripsy using the stone self-popping technique was significantly faster compared with the dusting technique with coefficient values of 14.12 minutes (95% confidence interval [CI] = 8.8-19.44) and 15.84 minutes (95% CI = 13.44-18.2) for OT and SDT, respectively. Conclusions: The stone self-popping technique with power at 60 W, frequency at 30 to 40 Hz, and energy at 1.5 to 2.0 J is a safe and effective modality for active treatment of renal stones. In comparison with the dusting mode, it resulted in significantly faster procedures (14.12 minutes) with similar SFRs.