Failures and complications of transurethral ureteroscopy in 297 cases: conventional rigid instruments vs. small caliber semirigid ureteroscopes.

To evaluate the safety and effectiveness of ureteroscopic stone manipulation, we retrospectively reviewed the failure and complication rates of two series of retrograde ureteroscopies (URS) according to the instrument used: the conventional rigid ureteroscopes and the new fiberoptic small size ureteroscopes. From July 1985 to December 1992, we performed 248 URS in 238 patients using a conventional rigid ureteroscope. From January 1992 to December 1992, we performed 49 URS in 47 patients using a semirigid ureteroscope. The failure rate was 14.5% in the first group of patients. The early and late complications observed were: urinary tract infections (UTI) in 22.5%, small mucosal lesions (false route) in 24.5%, full-thickness perforations in 11.2%, migration of the stone fragments into the retroperitoneum in 0.4% and the rupture of the tip of an alligator forceps into the ureteral lumen in 0.4%. Ureteral stenosis was observed in 1.6% of the cases. Often two or more complications occurred in the same patient. In the second group the failure rate was 10.2% and the complication rate 8.1%. We reported one case of ureteral perforation (2%), 3 mucosal lesions (6.1%) and UTI in 2 cases (4%). We conclude that URS using a small-caliber semirigid ureteroscope is a safer procedure than URS with conventional instruments. The majority of failures with semirigid scopes is related to the laser ineffectiveness in fragmenting the stone.