Flexible Ureterorenoscopy for Renal and Proximal Ureteral Stone in Patients with Previous Ureteral Stenting: Impact on Stone-Free Rate and Morbidity

Objective: To analyze results (stone-free rate [SFR]) and complications after flexible ureterorenoscopy (f-URS) for renal or lumbar ureteral lithiasis in patients with a previous ureteral stenting (US). Patients and Methods: We conducted a single-center retrospective study, including all f-URS procedures achieved in our department, between January 2004 and December 2010, for renal or lumbar ureteral urinary lithiasis. In total, 497 procedures were performed: 316 procedures in patients with a ureteral stent placed before the surgery for renal colic, sepsis, or renal failure (group 1) and 181 procedures in patients without US (group 2). Success was defined as a complete SFR at 6-month follow-up. Surgical morbidity was defined using the Clavien-Dindo grading system. Results: Groups 1 and 2 were well balanced in terms of demographic data, number, and size of stones. Ureteral location was significantly higher in group 1 (30.2% vs 16.3%, p=0.0006). Surgery characteristics were similar in both groups. By univariate analysis, SFR tended to be slightly higher in the group with prior ureteral stenting (72% vs 63%, p=0.05). SFR for ureteral location was also higher after previous ureteral stenting (81.5% vs 59.4%, p=0.023). By multivariate analysis, only stone size and number were correlated with f-URS failure. Complication rate was comparable in both groups (10.7% vs 11.8%, p=0.7). Conclusion: Technical aspects of the f-URS procedure were not modified by ureteral stenting. We found that f-URS in patients with ureteral stenting was not associated with a better SFR, except in case of ureteral location in univariate analysis. Ureteral stenting was not independently related to f-URS outcome by multivariate analysis.