Single-session ureteroscopy with holmium laser lithotripsy for multiple stones.

Multiple stones are found in 20-25% of patients with urolithiasis. The stone multiplicity is a powerful adverse factor influencing the treatment outcome after shockwave lithotripsy, although guidelines for the treatment of multiple stones have not been well established yet. Herein we report our most recent experience of a single-session ureteroscopy for multiple stones. Between September 2008 and December 2011, 51 patients with multiple stones (total 146 stones) in different locations (37unilateral, 14 bilateral) underwent a total of 65 ureteroscopic procedures. Operative time, stone-free rates and complications were evaluated. Stone-free status was defined as no fragments in the ureter and the absence of >2 mm fragments in the kidney. The mean stone number per patient was 2.9 ± 1.7 and the mean stone burden (cumulative stone length) was 21.5 ± 11.6 mm. The mean number of procedures was 1.3 ± 0.6. Overall, the stone-free rate after a single session was 80% (41/51). In patients with stone burden <20 mm and ≥20 mm, stone-free rates after a single session were 92% (23/25) and 69% (18/26), respectively. Multivariate analysis showed that the stone burden and the presence of impacted stones were the factors significantly influencing the treatment outcome. Stone location did not have a strong influence on the outcome. No major intraoperative complications were identified. Our findings suggest that ureteroscopy is an efficient treatment for multiple stones. For patients with stone burden <20 mm, either unilaterally or bilaterally, a single session of ureteroscopy is a favorable treatment option with a high stone-free rate.