[Extracorporeal shock wave lithotripsy using Dornier modified HM3 lithotripter comparison with the results by Dornier...

Ninety-four kidneys with renal stones less than or equal to 20 mm in diameter were treated by extracorporeal shock wave litotripsy (ESWL) using a Dornier modified HM3 lithotripter and the results were compared with those of 98 kidneys with similar size stones treated with a Dornier HM3 lithotripter. The Dornier modified HM3 lithotripter is equipped with a new type of shock wave generator with a reduced capacity for 30% less pressure peakes at the same voltage. It has an enlarged ellipsoid leading to a smaller focus and a reduced pressure per area at the shock wave entry into the skin. All treatments of modified HM3 litotripter series were performed under only intravenous analgosedation, without epidural anesthesia. The number of shock waves in the modified HM3 series ranged 900 to 6000, with the mean values of 2863 +/- 1234, which was 1.55 times as that in the Dornier HM3 series. Complete disintegration was achieved in 94 of 94 modified HM3 series kidneys and 98 of 98 kidneys of HM3 series. Complete removal of the stone was done at 72.6% in the modified HM3 series and at 70.4% in the HM3 series 3 months after ESWL. There were no severe complications in both modified HM3 series and HM3 series. Renal damage caused by ESWL was monitored by the level of urinary enzyme, N-acetyl-beta-glucosaminidase (NAG) and beta 2 microglobulin (beta 2MG) and the level of urinary protein. The levels of NAG, beta 2MG and urinary protein in the HM3 series were higher than those of the modified HM3 series.(ABSTRACT TRUNCATED AT 250 WORDS)