Numerical analysis of power dissipation requirement in magnetic hyperthermia problems

Control of the therapeutic temperature is essential in performing magnetic fluid hyperthermia. Thus, reliable predictions of the power dissipation are required to determine the correct dosage of magnetic particles to be injected into the cancerous tissue prior to treatment. To meet this requirement, the present study evaluates the power dissipation requirement for two magnetic hyperthermia problems reported in the literature. There is a significant challenge for solving the bio-heat transfer model for concentric bi-layered solid spheres. Consequently, the present study employs a hybrid technique based on Laplace transformation and a modified discretization scheme to solve the considered hyperthermia problems. Analytical solutions are provided to demonstrate the validity of the proposed approach. The unreliability of the results presented in the literature is then demonstrated using the proposed numerical scheme. In general, the results presented in this study show that the power dissipation required to maintain an effective temperature range in the tumor domain is related to the rate of temperature rise, the tumor size, the blood perfusion rate, and the tissue properties. In particular, the power dissipation should be increased for the cooling effect of blood perfusion or a smaller tumor volume.