[Extracorporeal piezoelectric lithotripsy by ultra-short waves using the EDAP LT01 device]

Three hundred and sixty one extracorporeal lithotripsies for renal, ureteric and bladder stones have been performed by means of a system of ultrasonographic detection and piezoelectric destruction (EDAP LT01). The localisation of the stone is achieved by a 5 MHz real time sectorial transducer situated in the centre of a small dish containing 320 piezoelectric elements concentrated in a source 5 mm wide by 15 mm high. The pressure recorded in vitro is 900 bars. The stone is easily detected in 87.2% of cases, difficult to detect in 10% of cases and impossible to detect in 28% of cases. By using a frequency of 1.25 to 5 per second, extracorporeal lithotripsy can be performed without any local, regional or general anaesthesia and without premedication in the 120 patients with a renal stone, reviewed between 1 and 3 months, 88 (73%) were considered to be complete successes. Ten (8%) were considered to be failures and 19 (21%) were considered to be partial successes. The best results were obtained in stones of the renal pelvis less than 20 mm in diameter. These results relate to a mean series which must take into account the successive improvements made to the lithotripter. Today, stone fragmentation is obtained in 93% of cases. Thirty six stones of the lumber and pelvic ureter were treated with success rates of 93% and 50%, respectively. Six bladder calculi were treated with a 50% success rate. Forty two patients were treated without being admitted to hospital.(ABSTRACT TRUNCATED AT 250 WORDS)