Transient Cavitation based Ultrasonic Litho tr ip tor Positioning Sys tern

Ab r t r act Focurred liquid rhock waver generate above a threrhofd prersure (- 1 MPa) in the focus region a transient cavitation field. The coincidence between this cavitation field and the kidney rtone can be used for the exact positioning of the lithotriptor. This can be visualized by a true real time ultrasonic camera conrirting of a 1 MHz transducer and a PVDF matrix (11 x 11 pixel) at receiving rgrtem. In contradiction to Rontgen methodr the influence of the acoustic inhomoguenous tissue is totally eliminated.