Is There a Winner? Prospective Randomized Controlled Trial Comparing SuperPulse Thulium Fiber Laser vs Pulse-Modulated High-Power Holmium:YAG Laser for Retrograde Intrarenal Surgery

Pulse-modulated holmium:YAG (Ho:YAG) and SuperPulse thulium fiber laser are high-power laser systems used for retrograde intrarenal surgery. We conducted a prospective randomized trial to compare lithotripsy efficiency, complications, and stone-free rates. Patients with CT-confirmed intrarenal stones between 5 and 20 mm were randomly assigned to pulse-modulated Ho:YAG (Moses 2.0, 120 W) or SuperPulse thulium fiber laser (60 W). The primary outcome was absolute (0 fragment) stone-free rate 6 weeks postoperatively evaluated by CT. Secondary outcomes included residual fragment size, laser efficiency, and postoperative complications. Categorical variables were compared using χ2 or Fisher exact tests. Continuous variables were analyzed with Mann-Whitney U tests. Sixty-six patients were randomized to pulse-modulated Ho:YAG (n = 33) or SuperPulse thulium fiber laser (n = 33). Absolute stone-free rates were 79% and 82%, respectively (P = .8). Less than 3 mm residual fragments were observed in 18% and 6.1% (P = .3) and ≥ 3 mm residual fragments in 3% and 12% (P = .4), respectively. Total energy used (3.4 vs 3.1 kJ, P = .8) and lasing time (9.4 vs 12.8 minutes, P = .3) were similar. Laser ablation efficiency (0.038 vs 0.055 mm3/J, P = .16), laser activity (46% vs 56%, P = .07), and laser ablation speed (0.40 vs 0.42 mm3/s, P > .9) did not differ. Emergency department visits (3.0% vs 6.1%, P > .9) and complications (6.1% vs 9.1%, P > .9) were similar. We found no discernible differences between the high-power pulse-modulated Ho:YAG and SuperPulse thulium fiber laser for treatment of renal stones between 5 and 20 mm in terms of stone-free rates by CT scan, laser efficiency, and complications in our single-center study.