Ureteroscopy may damage the ureter, and the complication risk is influenced by the forces needed to move the ureteroscope up and down the ureter.~Although a safety guidewire (SGW) is commonly recommended in order to reduce the complication rate it may well be that the SGW itself may inhibit the passage of the ureteroscope due to increased friction.~The forces needed to move the ureteroscope in the ureter have not been investigated properly.~The intention in this study is to measure the forces needed to advance and withdraw the ureteroscope in the ureter with and without the SGW in place.
The purpose of this study is to investigate to forces needed to passage the ureteroscope up and down the ureter with and without a safety guidewire in place.