Prospective Randomized Controlled Trial to Compare Dusting vs Fragmentation Using Thulium Fiber Laser in Retrograde Intrarenal Surgery.

Objective: To compare the dusting vs fragmentation modes with thulium fiber laser (TFL) in retrograde intrarenal surgery (RIRS) for upper tract stones using the same fixed low-power settings in both the arms. The primary objective was to compare the stone-free rate (SFR) and secondary objectives were to compare mean operating times, hospital stay duration, complication rates, need for secondary procedures, and laser efficacy. Materials and Methods: A prospective randomized trial, with patients having proximal ureteral or renal stones of 10–20 mm and planned for RIRS was done at a single institute. A total of 60 consecutively admitted patients with signed consent were included for randomization with 30 patients in each arm of dusting and fragmentation modes. Results: Median age in dusting and fragmentation arms of 41.5 and 45.5 years, median stone size of 10.45 and 12.25 mm, median stone volume of 351.6 and 490.7 mm³, and median stone density of 1263.5 HU in both arms with comparable hospital stay of median of 2 days in both arms. Lasing time was significantly lesser in the fragmentation group (20.5 minutes; interquartile range [IQR] 15.12–31.62) than in the dusting group (34.25 minutes, IQR 26.62–38.62, p < 0.001). Higher ablation speed for fragmentation mode (0.405 mm³/sec, IQR 0.337–0.635) than for dusting mode (0.17 mm³/sec, IQR 0.135–0.325, p < 0.001). SFRs and complication rates were comparable in both the arms. Conclusion: TFL in fragmentation mode has shorter lasing times and better laser efficacy than dusting mode with comparable minimal complications, SFRs, and hospital stay duration. Clinical Trial Registration number: CTRI050827. [ABSTRACT FROM AUTHOR]