High-power holmium laser versus pulsed thulium laser for ureteroscopic lithotripsy: Results of a randomized...

Current evidence indicates that the outcomes obtained with the holmium laser (Ho:YAG) and the thulium fiber laser (TFL) in the endoscopic treatment of upper urinary tract stones are at least equivalent. The recent introduction of the pulsed thulium laser (p-Tm:YAG) could result, due to its characteristics, in the ideal combination of its predecessors. The aim of this study was to compare the performance and outcomes between high-power Ho:YAG and p-Tm:YAG.

This prospective randomized clinical study included patients with a single renal or ureteral stone, who underwent retrograde endoscopic surgery.

A total of 122 patients were recruited, of whom 66 (54%) received treatment with the p-Tm:YAG laser. The overall stone-free rate was 65.1% for p-Tm:YAG and 62.5% for Ho:YAG (p = 0.76). Specifically, for renal stones, the stone-free rates were 60.9% vs 48.4% (p = 0.28), respectively. The median energy used in the p-Tm:YAG group was 4.71 kJ compared to 5.31 kJ in the Ho:YAG group (p = 0.28). The postoperative requirement for a double-J catheter was higher in the Ho:YAG group (67.8% vs 50%; p = 0.04). The analysis showed no statistically significant difference in the energy required to treat 1 mm³ of stone (20 J/mm³ for p-Tm:YAG vs 22 J/mm³ for Ho:YAG; p = 0.48).

Intracorporeal lithotripsy with p-Tm:YAG shows non-inferior results in terms of stone-free rates compared to high-power Ho:YAG. There is a trend in favor of p-Tm:YAG regarding the total energy required and a lower need for a subsequent double-J catheter, which should be corroborated by further studies in this field of urology.