Contralateral ureteroscopy performed at percutaneous nephrolithotomy: a unique evaluation of stone-free rates

Abstract

Purpose: Immediate stone-free rates of ureteroscopy are rarely reported. To establish accurate stone-free rates after ureteroscopy we assessed the safety and success of ureteroscopy for patients undergoing the procedure at contralateral percutaneous nephrolithotomy.

Materials and methods: From our prospectively collected, institutional review board approved, percutaneous nephrolithotomy database we identified patients who underwent contralateral ureteroscopy for urolithiasis at percutaneous nephrolithotomy from December 2001 to December 2008. Stone-free status was assessed with noncontrast computerized tomography on postoperative day 1.

Results: A total of 65 patients underwent ureteroscopy for urolithiasis at contralateral percutaneous nephrolithotomy. There were 63 patients available for review who had noncontrast computerized tomography on postoperative day 1. Immediate stone-free status was achieved after ureteroscopy in 37 of 63 patients (58.7%). The remaining 26 patients (41.3%) demonstrated a residual stone burden. Of these patients with residual stones after ureteroscopy 65.4% (17 of 26) had residual fragments of 1 to 3 mm and 34.6% (9 of 26) had residual stones larger than 3 mm. Three patients (4.8%) underwent repeat ureteroscopy at secondary percutaneous nephrolithotomy. There was no association of stone composition, patient age, stone location, gender or surgical complications with residual fragments (p>0.05).

Conclusions: Based on noncontrast computerized tomography 58.7% of patients who underwent ureteroscopy were rendered immediately stone-free. When residual passable stone fragments less than 3 mm were included the success rate increased to 85.7%. We found no association between characteristics of patients, stones or procedures and residual fragments.