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

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.

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.

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).

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.