Changing surgical aspects of urinary stone disease.

Surgical management of urinary calculous disease has changed dramatically in the past decade. The development of percutaneous nephrostomy techniques has allowed new access to upper tract stones. Percutaneous removal of large calculi was made possible by the development of ultrasonic and electrohydraulic lithotripsy. All upper tract calculi can now be removed in 70 to 100 per cent of cases with minimal complications. Nephrostolithotomy has reduced transfusion rates and hospitalization costs and has markedly shortened convalescence periods compared with open surgery. Ureteroscopy followed nephrostolithotomy as advanced fiberoptic technology allowed the development of the small-caliber instruments required for this procedure. With experience, successful stone retrieval has occurred in 90 per cent or more of cases, again with minimal complications. As nephrostolithotomy and ureteroscopy have become available, the subspecialty of endourology has emerged and significantly changed the management of urinary tract calculi. Perhaps the most significant advance in stone therapy has been the design and implementation of extracorporeal shock wave lithotripsy. With this noninvasive technique, most renal and proximal ureteral calculi can be effectively treated with minimal morbidity and convalescence. Research in lithotripter design is continuing, with more advanced and effective machines on the horizon. The applicability of extracorporeal therapy for the treatment of biliary tract calculi is currently under investigation. Finally, one should not disparage medical therapy for recurrent nephrolithiasis. A comprehensive metabolic evaluation combined with selective medical therapy provides almost complete relief from recurrent stone formation and makes medical therapy an integral component of treating the patient with renal or ureteral calculi.