Thermo-mechanical analysis of soft tissue in local hyperthermia treatment

Magnetic fluid hyperthermia is a new subclass of hyperthermia cancer treatment that can selectively heat up a tumor without damaging the surrounding healthy tissues. Some authors studied the temperature distribution of a magnetically mediated tumor assuming a homogeneous distribution of nanoparticles inside the tumor. Viscoelastic behavior of cancerous and healthy tissues have been studied in various articles and many methods have been introduced for computation of physical-mechanical properties of the tissue considering the fact that thermo-mechanical properties of the tissue completely change when the tissue becomes cancerous. Purpose of this study is to investigate thermo-visco-elastic behavior of tumorous and healthy bovine liver tissue. Therefore, the tumor is simulated as a solid sphere having radius denoted as r along with the surrounding healthy tissue. Any discontinuity between cancerous and healthy tissues is neglected. Since the resulting constitutive equations are highly complex, the stress and displacement fields were calculated by using finite difference method. An experimental test was designed to validate numerical results. Numerical results are found to be in good agreement with experimental data and with other references on homogeneous dispersion of nanoparticles.