Stenting or not prior to extracorporeal shockwave lithotripsy for ureteral stones? Results of a prospective randomized study.

Purpose: To determine the need for pre-treatment stenting in patients undergoing extracorporeal shockwave lithotripsy (ESWL) for ureteral stones sized 4-10 mm.

Methods: A prospective randomized study was conducted between September 2009 and March 2011. Included 156 patients randomized in stented and non-stented groups and underwent a maximum of 3 ESWL sessions. Radiographic follow-up was used to assess the stone fragmentation and clearance. Results were compared in terms of stone-free rates, post-treatment morbidity and complications.

Results: Overall efficacy was 76.9%. Stone-free rates were statistically significantly lower (P = 0.026) in the stented group (68.6%) compared to the non-stented ones (83.7%). Furthermore, stenting was significantly correlated with post-treatment lower urinary tract symptoms (P ≤ 0.001), need for more ESWL sessions (P = 0.019) and possibility for operation due to ESWL failure (P = 0.026). A multivariate analysis was conducted to identify the parameters which may predict complete stone removal after ESWL. Stone size (P = 0.026), stone location (P = 0.011) and stenting (P = 0.007) were the most significant factors.

Conclusions: ESWL is an efficient and safe treatment for 4- to 10-mm ureteral stones. Pre-treatment stenting is limiting stone-free rates and is significantly influencing post-ESWL morbidity and quality of life in a negative manner, while it contributes minimally to the prophylaxis of complications.