Ureteroscopic Laser Lithotripsy for Upper Urinary Tract Calculi With Active Fragment Extraction and Computerized Tomography Followup

Abstract

Management of fragments generated by ureteroscopic laser lithotripsy remains controversial. In this study we explored the impact of active fragment extraction after ureteroscopic laser lithotripsy on stone clearance. A total of 69 patients with 3 or less upper urinary tract calculi (5 to 15 mm) demonstrated on preoperative CT were prospectively evaluated. Stones were translocated to a dependent upper pole calix where laser lithotripsy was performed. An attempt was made to clear all fragments using tipless stone baskets. One month after surgery stone clearance was evaluated exclusively with noncontrast spiral CT. In 58 patients undergoing surgery on protocol, average stone burden was 9.4 +/- 3.4 mm and was significantly smaller in 44 patients with stones in a solitary location (8.5 +/- 2.9 mm) than in 14 patients with stones in multiple locations (12.3 +/- 3.2 mm, p <0.001). Primary stone location was categorized as renal nonlower pole (in 16), renal lower pole (in 19) and proximal ureter (in 23). Average operative time (43.7 +/- 18.4 minutes) was unaffected by stone location or multiplicity after controlling for stone size (p >0.05). Stone clearance rates were not affected by stone location or multiplicity, with overall success rates of 54%, 84% and 95% at fragment thresholds of 0, 2 and 4 mm, respectively (p >0.05). Ureteroscopic laser lithotripsy with active fragment extraction was time efficient and highly effective. Sensitive postoperative imaging reveals the challenge of achieving a true stone-free state. We were unable to demonstrate an impact of stone location on stone-free rates.