Developments in the ureteroscopes, techniques and accessories associated with laser lithotripsy

Summary

Two stages in the development of the technique of laser lithotripsy are described. In the first series, spanning 1985–1988, three consecutive groups of patients are compared. In the first 100 patients, 11.5-F ureteroscopes were used. Access on first retrograde attempt was successful in 73%; 3% developed strictures; the ureteric perforation rate was 7%; and 12% required nephrostomy drainage. These results contrast with those of the third group in this series, consisting of 200 patients using a miniaturised ureteroscope. Access on the first retrograde attempt was successful in 99%. There were no strictures, no perforations and no requirements for nephrostomy drainage. (The second group of 100 patients using a range of rigid ureteroscopes was intermediate in its complication rate: 2% developed strictures, the ureteric perforation rate was 3%, and 6% required nephrostomy drainage.) In the second series, spanning 1989–1990, the procedures were performed by all grades of urologists using miniaturised endoscopes. An in-depth audit was performed and each patient was followed until completely clear of fragments. The stones were successfully accessed on the first attempt in 213 cases (89%). In group A (139 patients, no basket used) 32 renal units (23%) were cleared of stone fragments immediately following the procedure, rising to 78 units (56%) by 3 months and 99 units (71%) beyond 3 months follow-up. Some fragments remained in 40 renal units and were cleared by further ureteroscopy, ESWL or PCNL, with the exception of 1 patient who had small residual fragments despite ESWL for fragments flushed to the kidney. In group B (74 patients, basked used) 41 renal units (55%) were cleared of stone fragments immediately following the procedure, rising to 66 (86%) by 3 months. The remaining patients were cleared by additional ESWL for a renal fragment (1 case) or a second ureteroscopy (7 cases). Significant complications have been avoided by the adoption of small-calibre ureteroscopes. Simple fragmentation of a stone leaving the debris to pass spontaneously is less effective than making an attempt to clear the ureter at the time of the procedure.