[Biological effects of interacting shock waves. A modeling study of the effects of interacting shock waves using...

The effects of high-energy shock wave on tissues were discussed in literature. The shock wave sources which were used for experiments were developed for stone fragmentation. The side effects of the applicators are generally low. Increase of shock wave pressure induce bigger negative pressure amplitude and this may cause significantly bigger side effects. We used tow shock waves, with time interval of 5 microseconds. In our opinion, the first shock wave causes acoustic inhomogenity in shock wave focus and therefore second shock wave acts in a region with different acoustic parameters. The second shock wave may loss energy in the focus area by dissipation or absorption. We termed the coupled shock waves as "interacting shock waves".

Hemolysis of erythrocytes was used for examination of biological toxicity. Shock wave pressure was 80 MPa, the ratio of positive to negative pressure of single shock waves is 30. For correlation we applied 50 and 100 single shock waves and 50 or 100 couples of two shock waves. Hemolysis after 50 simple shock waves was 4.28 times lower compared with hemolysis after the same number of coupled shock waves (interacting shock waves).

After 50 couples of shock waves hemolysis is 2.14 times higher compared with 100 single shock waves. This result suggests that the hypothesis of some interaction existing between two shocks applied in a very short time interval make future study rightful.