Extracorporeal shock wave lithotripsy for radiolucent stones.

Eleven patients with radiolucent urinary calculi were treated with shock wave lithotripsy. Nine of these patients experienced successful fragmentation of their stones and subsequent spontaneous passage of the calculi fragments. The majority of the stones were composed of uric acid alone or a mixture of uric acid and calcium oxalate. One stone with metabolites of triamterene also fragmented well. Uric acid calculi can be treated successfully with shock wave lithotripsy using adequate visualization by contrast injection.