[Operative fiberoptic nephroureteroscope--removal of renal and upper ureteral stones].

Two types of operative fiberoptic nephroureteroscopes were developed with the cooperation of the Olympus Optical Company mainly to remove the upper urinary tract calculi. Removal of the renal and upper ureteral stones was attempted in nine cases. The ureter was dilated with olive tip, balloon and Teflon dilators alone or in combination. The combination of balloon and Teflon dilators seemed the most promising. As a result of ureteral dilation, operative fiberoptic nephroureteroscopes, 4.5 mm and 3.5 mm in diameter, could be passed into the ureter in all the cases and the stones could be visualized clearly. Four of the 7 upper ureteral stones and 1 of the 2 pelvic stones could be removed. The success ratio was 56%. The method of stone removal still requires improvement. At present, application of the operative fiberoptic nephroureteroscope is indicated for upper ureteral and renal stones less than 1.0 cm in diameter. With the improved techniques of stone removal using this fiberscope, the indications of extracorporeal shock-wave lithotripsy or percutaneous nephrolithotripsy will probably be greatly reduced in the near future.