Pyelolithotomy improves while extracorporeal lithotripsy impairs kidney function

Purpose: Extracorporeal shock wave lithotripsy (ESWL dagger) causes acute d epression of kidney function, which chronically returns to baseline levels. This sequala could indicate chronic regression of acute lesions or a balan ce between lesions and relief of obstruction. We compared changes in kidney function 1 week and 3 months after ESWL and pyelolithotomy. Materials and Methods: A group of 17 women and 13 men 28 to 71 years old wi th 0.6 to 3 cm. stones received 1,800 to 3,200 shock waves by an electromag netic Lithotriptor. Another group of 21 women and 9 men 35 to 76 years old with 2.5 to 3.8 cm. stones underwent Gil-Vernet intra-sinus pyelolithotomy. Split renal plasma flow, glomerular filtration rate and mean parenchymal t ransit times of nonreabsorbable filtrate solutes were measured by dual gamm a camera renography, and plasma clearances of (99m)technetium diethylenetri aminepentaacetic acid and (131)orthoiodohippurate acid. Results: ESWL caused acute deterioration and chronic restoration of baselin e parameters of the treated kidney, and small but sometimes irreversible da mage to plasma flow to the untreated kidney, especially in obese patients. In contrast, pyelolithotomy acutely and chronically improved function of th e treated kidney, and normalized parenchymal transit times of radiotracers. Conclusions: ESWL does not achieve substantial improvements in kidney funct ion, which can be achieved by other methods of stone removal.