Operative Ureterorenoscopy for Endoscopic Removal of Ureteric Calculi

Abstract

Progress in the miniaturization of optical systems has made ureteroscopy possible. As well as the flexible instruments used in gastroenterology, we also employ inelastic metal instruments which allow optical control of the ureter as described by Perez-Castro and Pineiro¹. We first reported our experience with this technique in 1981² and others have followed^3,4. Two aspects have to be taken into consideration in the application of ureterorenoscopy: (i) the technique of inserting the instrument; and (ii) the manipulation in the ureter and application of ultrasound to fragment concrements. The use of ultrasound in the ureter seems particularly problematic because of possible damage to the urothelium. In order to test the direct effect of ultrasound on the urothelium we carried out some animal experiments. For anatomical reasons, we could not test the direct effect of ultrasound on the ureteric wall in dogs and so used the bladder wall instead, assessing both the immediate and long-term effects (after 40 days).