Estimation of Electrical Conductivity from Radiofrequency Hyperthermia Therapy for Cancer Treatment by Levenberg Marquardt Method

Abstract

Introduction: The radiofrequency hyperthermia is a technique that by induction of the electromagnetic waves produces the heating in the biological tissues. The increase in body temperature in a range of 40 °C to 46 °C causing heat-induced necrosis, protein inactivity, and inhibition of DNA recovery mechanisms in the cancer cell. The application of this therapy depends on parameters like the frequency and power and physical properties of the tissue, which vary from person to person. One of the important properties is the electrical conductivity of the tissue, which varies depending on the tissue and frequency. In this paper, the electrical conductivity estimation is performed in hyperthermia therapy with different frequencies. Methodology: The estimation process of electrical conductivity is carried out through the Levenberg Marquardt method. The process is performed on simulated experimental data and mathematical model of the system with different frequencies. The geometry used is a copper coil that induces radiofrequency to a domain located in the center of the coil. Results: The estimation of electrical conductivity is obtained to different frequencies from radiofrequency hyperthermia therapy for cancer treatment by the Levenberg Marquardt method. Also, these results allow that by identifying the electrical conductivity of each patient. Conclusions: The estimation of physical properties in the application of cancer treatment is important, in this case with radiofrequency hyperthermia therapy, because it is possible to plan appropriate treatment, due to a better knowledge of the system.