Percutaneous nephroscopy: a review of the physical properties, suitability and cost of the instruments.

The physical properties, suitability and cost of six instruments used for elective percutaneous renal endoscopy have been evaluated. Three were rigid and three were flexible. The optics, flow rate and accessories of the rigid instruments have been demonstrated to be superior to the flexible instruments. Flexible instruments, however, were used in 15% of our 70 elective percutaneous operations. The 21-Charr cystoscope was adequate for extracting smaller calculi, but it was necessary to use the Storz and Wolf rigid nephroscopes when ultrasonic disruption was required. Based on our data, improvements and modifications to both flexible and rigid instrument design are suggested.