Painless piezoelectric extracorporeal lithotripsy.

A total of 693 stones in 438 renoureteral units from 426 patients 4 months to 84 years old was treated with a mobile piezoelectric lithotriptor using ultrasound stone localization. Of the units 37 per cent had solitary stones smaller than 1.5 cm. in diameter, (group 1), 32 per cent had multiple stones up to this size (group 2), 21 per cent had stones 1.6 to 2.5 cm. in diameter (group 3) and 10 per cent had calculi larger than 2.5 cm. in diameter (group 4). No sedation or analgesics were necessary in 96.2 per cent of the treatments. Of all stones 97.2 per cent were disintegrated, with 39 per cent of the units requiring repeat treatments usually on an outpatient basis. Of the patients 82 per cent had transient hematuria, 6 per cent had fever and 28 per cent temporarily took some type of analgesics within the first 3 months after treatment. Nine per cent of the patients required postoperative ancillary interventions. After 3 months 92 per cent of the renoureteral units in group 1, 73 per cent in group 2, 74 per cent in group 3 and 50 per cent in group 4 were free of stones. Piezoelectric extracorporeal lithotripsy proved to be as efficient as spark-gap lithotripsy, yet it was essentially painless. Ultrasound localization permits treatment of all renal stones but it restricts lithotripsy of ureteral stones to the most proximal and distal fourths of the ureter.