Experience in ureteroscopy for managing urolithiasis in one clinic. when does quantity transform into quality?

Introduction. In recent years, there has been an increasing role of ureteroscopy in managing urinary tract calculi of various locations. Several studies have reported the relationship between the efficacy and safety of ureteroscopic interventions and surgeon’s skills and hospital caseload volume. The aim of our study was to assess the effectiveness of urethroscopic stone removal, the changes in treatment effectiveness, frequency and types of complications along with gaining experience in these interventions. Materials and methods. We analyzed 4031 urolithiasis patients who were admitted to our urological department and underwent ureteroscopy from 2001 to 2013. To determine the effectiveness and safety of the method, as the experience gained, the time of observation was divided into three periods: from 2000 to 2004, from 2004 to 2009, from 2009 to 2013. The parameters were evaluated for the entire observation time and for each period. Results. Complete fragmentation of the stones was observed in 3628 (90%) patients, partial - in 219 (5.4%). No treatment effect was observed in 138 (3.4%) patients. The greatest effectiveness (96.94%) was seen in stones in the lower third of the ureter. The proportion of unsuccessful ureteroscopies was 5.7%, 4.5% and 3.5% for the periods 2000 -2004, 2005-2009 and 2009-2013, respectively (p=0.027). The incidence of acute postoperative pyelonephritis in the corresponding periods was 15.4%, 3.3% and 2.9% (p<0.001). Conclusion. Ureteroscopy is an effective and safe treatment modality for managing upper urinary tract calculi. It is most effective in treating distal ureteral stones. The increase in the treatment effectiveness and the reduction in the incidence of complications along with gaining experience, suggests that these interventions should be practiced mainly in urology centers specializing in the care of patients with urolithiasis.