AN ANALYTIC SOLUTION FOR ENERGY DEPOSITION IN MODEL SPHERICAL TUMORS UNDERGOING ULTRASOUND-HYPERTHERMIA TREATMENTS

In this paper, we develop a method to predict the energy deposition in rumours undergoing ultrasound-hyperthermia treatments. Energy deposit ions are calculated using an exact, analytic solution to the problem o f ultrasound scattering from a spherical tumour. The biological tissue s are modelled as solid, lossy elastic media so that (i) transverse-wa ve modes, in addition to longitudinal-wave modes, are considered, and (ii) mode coupling is fully accounted for during the scattering. The m odel tumour is of arbitrary size and no restrictions are placed on its material parameters relative to the surrounding tissue. Simpler analy tic results are given for rumours that differ in densities and rigidit ies only slightly from the surrounding tissue. We briefly discuss how the above analysis could be extended to more complex systems, i.e., ir regularly shaped tumours.