Effect of difference in shear modulus of biological tissue on heat source distribution of high-intensity focused ultrasound estimated by acoustic radiation force imaging

High-intensity focused ultrasound (HIFU) is a novel noninvasive cancer treatment that is expected to be a potential alternative to conventional therapies. In the treatment, the accurate prediction of the ultrasonic heat source prior to therapeutic exposure is important for safety and efficacy. Acoustic radiation force imaging using a short HIFU burst has been proposed as a method for this prediction from the distribution of the tissue displacement. In this study, the effect of the difference in shear modulus on the estimation of the HIFU heat source was experimentally investigated by applying the imaging method to different biological tissues: chicken breast and chicken liver tissues. The result suggested that HIFU radiation force imaging has the potential to determine the HIFU power for appropriate treatment quantitatively from the displacement, even in different tissues with different shear moduli.