The Experimental Study of Stone Fracture by Shock Wave (II)

Kang, Sang Jee; Choi, Sung Hyup

Abstract

Since Chaussy, Schmiedt et al. began using ESWL on the renal calculi in 1980, the treatment of stone disease has been revolutionized. Now, an experimental study for the systematic investigation of ESWL is needed. This report presents an experimental study in vitro utilizing piezoelectric ESWL(EDAP LT-01 and "Die Stone" for the purposes of the effects of varying frequencies, stone burdens and powers. The following results were obtained : 1. In the same sized stones with constant power of 100%, the effects of increasing frequency from 2.5 to 40 times/sec showed that mean storage was increased despite of decreases duration for complete fragmentation of the stone less than 3mm in diameter, therefore the more lowering frequency, the more increasing effectiveness of the stone fragmentation. 2. When the stone burden was increased from 1cm(3) to 2cm(3) with constant power of 100% storage and duration for complete fragmentation of the stone were markedly increased about 8.10 and 8.06 times respectively. 3. In 1cm3 of the stone burden with constant frequency of 10 times/sec, when power was increased, mean storage and duration were decreased for complete fragmentation of the stone. 4. Fragmentation of the stone with lower frequency was fractured into small pieces relatively, but with higher frequency, fractured into large pieces initially, thereafter fractured into small pieces. 5. More gas bubbles were produced on the anterior and posterior surfaces of the stone with higher frequency than lower frequency.