XIX Sympozjum Srodowiskowe PTZE - materialy.pdf

XIX Sympozjum PTZE, Worliny 2009
TEMPERATURE DEPENDENCE IN HUMAN BODY
FROM MODEL PARAMETERS IN RF HYPERTHERMIA
Eugeniusz Kurgan, Piotr Gas
AGH University of Science and Technology
Deptartment of Electrical and Power Control Engineering
al. Mickiewicza 30, 30-059 Kraków, Poland
e-mail: kurgan@agh.edu.pl, piotr.gas@agh.edu.pl
Abstract: Knowledge of the temperature distribution in human body is of great importance in hyperthermial
treatment of tumors. First distribution of induced current density in tissues is calculated and next bioheat equation is
solved. Dependence of sensitivity of the maximum temperature distribution in the body from different model
parameters are calculated.
Keywords: hyperthermia, Specific Absorption Rate, finite element method.
Introduction
Electromagnetically induced current in radiofrequency range has recently become the
preferred mode of energy delivery for the tumor destruction or sensitization. The high current
density near the tumor generates heat which rapidly increases the tissue temperature, causing
desiccation and protein structural change in macromolecules. In comparison with other
methods as, for example, high-energy direct-current, the advantages of radiofrequency
radiation therapy are that energy can be delivered in a graded manner by changing exciting
current density, it does not require general anesthesia, it can produce a homogeneous region
of necrosis. The synergistic behavior between hyperthermia and chemo- and radiotherapy is a
well-known phenomenon and in the last time hyperthermia experiences increasing attention
of medical world [1].
In this article distribution of the electromagnetic field components and temperature are
calculated. Knowledge of temperature distribution in human body is of great importance in
hyperthermial treatment of tumors. First distribution of induced current density in tissues is
calculated and next bioheat equation is solved. Computed temperature distribution allow as
optimal determination of electric parameters exciting coil in such a way that temperature attain
its maximum value in the tumor and surrounding tissues.
Main equations
Around the human body a cylindrical coil with excitation current is placed as in Figure 1.
91