The paper presents a numerical algorithm for simulating the bio -heat equation optimized for calculation the temperature field and generation of volumetric lesions in biological tissue irradiated by high intensity focused ultrasound. Single focus irradiations were studied for three different peak power regimes with the same total energy balanced by the pulse duration: a harmonic regime, typically used in conventional noninvasive ultrasound surgery, and two shock-wave regimes with different peak intensity. The temperature and thermal dose distributions achieved in a single focus over the time between the focus shift of the therapeutic ultrasound array along the irradiation trajectory in tissue were calculated. It was shown that the use of shock-wave irradiations makes it possible to obtain local tissue destruction for heating time on the order of milliseconds.
$^1$Faculty of Physics, Lomonosov Moscow State University