Intracorporeal electrohydraulic lithotripsy of ureteral and renal calculi using small caliber (1.9F) electrohydraulic lithotripsy probes

Purpose: The development of 1.9F or smaller electrohydraulic lithotripsy probes has facilitated the use of this form of lithotripsy via miniature rigid and flexible ureteroscopes. We report our experience with ureteroscopic intracorporeal lithotripsy using 1.9F electrohydraulic lithotripsy probes. Materials and Methods: A total of 45 patients (32 ureteral and 57 renal calculi) underwent retrograde rigid (microscopic to 6F short) or flexible (7.5 and 9.4F) ureteroscopy with electrohydraulic lithotripsy using 1.9F electrohydraulic lithotripsy probes. In 17 patients (38%) there were 37 lower pole caliceal calculi (41%). Stone size ranged from 3 to 30 mm. (mean 8.5). Results: Electrohydraulic lithotripsy resulted in successful fragmentation (that is 2 mm. or smaller fragments) in 98% of patients overall. It was successful after failure of HM-3 extracorporeal shock wave lithotripsy in 10 patients and after failed lithotripsy with the 140 mJ. tunable dye laser in 7. Electrohydraulic lithotripsy resulted in successful fragmentation of 94% of lower pole caliceal stones. No intraoperative complications and no significant ureteral or renal mucosal damage were noted. Fever developed postoperatively in 2 patients (4.4%) with negative urine cultures. Postoperatively an indwelling stent was placed for 2 weeks or less in 71% of patients and no stents were placed due to preoperative stenting in 29%. Average hospital stay was 0.8 days (range 0 to 4). Followup imaging in 38 patients (84%) at a mean of 8.7 months (range 2 to 28) revealed stone-free rates of 92% overall and 87% in patients with lower pole renal calculi. No patient had a ureteral or infundibular stricture postoperatively. Conclusions: The development of 1.9F or smaller electrohydraulic lithotripsy probes provides the urologist with a safe, highly effective and inexpensive method for performing intracorporeal lithotripsy throughout the entire upper urinary tract via rigid or flexible ureteroscopes. Furthermore, for the ureteroscopic treatment of lower pole renal calculi electrohydraulic lithotripsy is the only form of intracorporeal lithotripsy sufficiently malleable to allow routine access.