Low-power holmium laser for the management of urinary tract calculi, strictures, and tumors

Background and Purpose: Introduction of the holmium laser has provided an i ndispensable tool for the management of urinary tract stones, strictures, a nd superficial urothelial tumors. While full-power holmium lasers are requi red for laser resection of the prostate, lower-power devices can be utilize d for all cases of stone fragmentation and stricture incision and most case s of superficial urothelial tumors. Herein, we report our initial experienc e in utilizing a low-power holmium laser in our endourologic practice. Patients amd Methods: Over a 6-month period, we have utilized both low-powe r (25 W) and full-power (80 W) holmium lasers to fragment urinary tract sto nes, incise ureteral or urethral strictures, and ablate superficial urothel ial tumors. A series of 80 consecutive patients were assessed prospectively . Laser fibers with a diameter of 200 mum and 365 mum were employed with po wer settings of 6.4 to 10 W, Laser fiber size and power settings were simil ar for the low- and full-power devices. Results: Overall, 95% of the stones were completely fragmented, with a ston e-free rate at 3 months of 92%, All strictures were incised, with a 91% pat ency rate at 3 months. Complete tumor ablation was attained in 70%, with a tumor-free rate of 60% at 3 months. Results were equivalent for the low- an d full-power lasers, The 200-mum laser fiber allowed adequate access throug hout the upper urinary tract during flexible ureteroscopy and flexible neph roscopy. The 365-mum laser fiber was employed via rigid and semirigid endos copes. Conclusions: A low-power holmium laser supplies adequate fragmentation and incision power for virtually all endourologic cases. It also provides ablat ive power in most situations. The only current urologic application that ca nnot he performed with the low-power device is laser prostatic resection, w hich requires 60 to 80 W of power. The reduced-power holmium laser should b e considered as a low-cost alternative for the management of urinary tract stones, strictures, and urothelial tumors, especially in centers where lase r prostatic resection is not performed.