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

Han, Chang Sup; Choi, Sung Hyup

Abstract

An experimental study in vitro using piezoelectric extracorporeal shock wave lithotriptor(EDAP LT-01) and urinary stones removed from the patients by surgical method has been performed. The purposes were 1) to correlate the stone components and sizes with the storage of complete fragmentation, 2) to examine the screening effect and 3) to observe the stone fracture mechanism in urinary stones. The following results were obtained. 1. Tribasic calcium phosphate stone, magnesium ammonium phosphate stone and uric acid stone fractured more easily than calcium oxalate stone. In the case of small stones(diameter 0.5 cm), all stones fractured at relatively low storage. Large stones (diameter 1.5 cm) fractured at high storage with wide variations according to components. 2. Magnesium ammonium phosphate stones tested to observe for screening effect showed that a high storage was needed for complete fragmentation(about 2 times) when the stone debris was not removed. 3. Urinary stones fractured first on the front surface. When the stones showed lamellae, which were separated first by shock wave, thereafter each lamella was broken.