Influence of stone size, location and impaction on the success of ureteroscopic pneumolithotripsy.

This study was conducted on 336 patients that had undergone ureteroscopic pneumolithotripsy for ureteric stones between August 2005 and June 2008. Patient data were analyzed with respect to stone localization, size and impaction. All ureterorenoscopic procedures were performed under general anesthesia using a 9.5F rigid ureteroscope. A plain film of the kidney ureter bladder was performed on the first postoperative day and week 4 to evaluate treatment efficacy. Patient age was 42, 63+/-15 (14-77) yr. Mean stone size for all groups was 9.77+/-4mm (5-20 mm). A total of 336 patients were treated with ureteroscopic pneumolithotripsy, 129 female and 207 male. The overall initial success rate was 85.71%. The success rate of ureteroscopic pneumolithotripsy, proximal, middle and distal ureter, for Stone location, 76.54%, 85.48%, 90.74%, for Stone size (>10 mm) 54%, 77%, 88 % and for Stone impaction; 50%, 75,6%, 85,4% respectively. There was a statistically significant difference between stone free rates with respect to the proximal ureter stone, increasing stone size (>10 mm) and stone impaction (p<0.05) and a positive correlation with the operative complication rate. It is concluded that it is possible to achieve high success and low complication rates in pneumolithotripsy for distal ureteric stones. Nevertheless, the success rate decreases and complication rate increases with stone locations close to the proximal ureter. Complication rate increases with increasing stone size and/or impacted ureteral stones.