Effect of effective tissue conductivity on thermal dose distributions of living tissue with directional blood flow during thermal therapy

Abstract This study proposes a modified transient bioheat transfer equation based on combing the porous medium property and the scalar effective thermal conductivity equation in order to include the directional effect of blood flow. By applying the porous medium model to describe the collective behavior of the heat transfer in living tissue with many small blood vessels, an analytical solution can be obtained by Green's function. Simulation results quantitatively show that the blood perfusion rate, the averaged blood velocity, the porosity and the heating period are the crucial factors determining the distribution of thermal dose for thermal therapies. In addition, longer heating schemes induce dependencies of both the blood perfusion and the enhanced thermal conductivity on increased temperature.

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