Retrograde Intrarenal Surgery in Treatment of Nephrolithiasis: Is a 100% Stone-Free Rate Achievable?

Abstract

To achieve an almost 100% stone-free rate by means of further developing and standardizing the procedure. 100 consecutive patients with single or multiple renal calculi were prospectively enrolled in the study. Flexible ureterorenoscopy was performed as a completely standardized operation by the same two experienced surgeons. Primary outcome was an "endoscopic" (immediate) stone-free status as determined by endoscopic inspection at the end of surgery. In cases of residual fragments, a reevaluation by CT was performed after 3 months. The endoscopic stone-free rate was 97%. In three patients with a cumulative stone size >20 mm, a completely stone-free status could not be achieved in the primary procedure. In these patients, a CT scan after 3 months showed complete clearance from all residual fragments in two; this translates into a primary (after one procedure) stone-free rate after 3 months of 99%. Medium cumulative stone size was 9.8 mm (4-40 mm); in 44 patients, multiple calculi were extracted. Forty-nine patients received a ureteral stent at the end of the operation; two patients had to have stent placement for new onset hydronephrosis and/or colicky pain or fever. Overall complication rate was 7%. Results are limited, because no routine CT scan was used to evaluate stone clearance. By means of a standardized surgical approach and use of technical equipment of the newest generation, it is possible to achieve very high stone-free rates without compromising safety. This approach, however, necessitates use of considerable resources, both technical/surgical and financial.