Experience with the holmium laser as an endoscopic lithotrite

Objectives. To study, in a clinical series, the safety and efficacy of holmium laser energy applied as an endoscopic lithotrite. Methods. Over a 2-year period, patients with urinary tract calculi were treated endoscopically with the holmium laser lithotripter, and data were gathered prospectively. Holmium lasers with maximum outputs of 15, 25, and 60 W were used. Various low water density, quartz fiber delivery systems were developed for specific applications. In addition, various combinations of endoscopes and laser fibers were employed. Results. A total of 63 patients with 75 calculi were treated. All calculi were cleared endoscopically. Minimal variation in laser efficiency was noted with different stone compositions, including cystine. Thirty-three of 34 ureteral calculi were treated to completion in one sitting (97%). Twenty-nine renal stone burdens were treated with the holmium laser, 26 of which were treated solely in a retrograde fashion. Of the latter, 23 (88.5%) required only a single sitting. Complications from holmium laser energy, including ureteral stricture disease, were not encountered in this series. Patients with complex, large stone burdens were treated to completion without sequelae. The combination of the actively deflectable, flexible ureteroscope and 200-mu m fiber facilitated clearance of 18 lower-pole caliceal calculi. Three patients with partial staghorn stone burdens averaging 30 mm in diameter were treated ureteroscopically. Chronic urinary infections that were problematic preoperatively completely resolved after therapy. All 12 patients who had large bladder calculi with a mean diameter of 55.8 mm were treated to completion in one sitting. Conclusions. Holmium laser energy is uniquely suited to treat all urinary calculi safely and effectively.