A 2-year experience with the Wolf piezoelectric lithotripter: impact of repeat treatment on results and complications.

During a 2-year period, 884 extracorporeal piezoelectric lithotripsy treatments have been performed on stones in 388 renal units (kidney and upper ureter) using a Wolf Piezolith device.* Lithotripsy routinely was performed on an outpatient basis without use of anesthesia or premedication. Often, the maximum number of pulses allowable by a Food and Drug Administration protocol (4,000) was delivered and retreatments frequently occurred on successive days. Of the patients 75% were stone-free 3 months after treatment, while another 20% had only residual small fragments. No intrarenal or perinephric hematomas were observed and only 1 patient has had hypertension requiring medication. Renal colic from passage of stone fragments occurred in only 10% of the patients. An aggressive treatment policy using repeat treatments as necessary provides for superior results with this device without an incision or complication.