A model for impedance determinations and power deposition characterization in three-electrode configurations for capacitive radio frequency hyperthermia--Part B: Current flow and power deposition

Numerical model for RF capacitive regional deep hyperthermia in pelvic tumors

A numerical model based on Finite Element Method (FEM) for the prediction of power density distribution and temperature during RF-capacitive hyperthermia treatment has been presented in the paper and the results are discussed. In particular the models are related to the treatment of pelvic tumors where it is more difficult to localize and focus heat in deep regions. The geometrical and physical model of the patient is reconstructed with a segmentation procedure by means of dedicated software. The geometrical meshed model has been used as input for the solution of coupled electromagnetic and thermal problems. A deep analysis of different configurations derived from specific scientific literature of the last years has been presented in the paper and discussed. The results obtained by FEM analyses have demonstrated the suitability of this method for the prediction of power and temperature distribution during RF capacitive hyperthermia and that the calculation procedure is an efficient mean to evaluate the efficacy of the heating system.

Control of specific absorption rate distribution using capacitive electrodes and inductive aperture-type applicators: implications for radiofrequency hyperthermia

A method of controlling the specific absorption rate (SAR) distribution in radiofrequency hyperthermia is proposed. The superposition of the current density associated with capacitively coupled electrodes and that associated with H-field coupled inductive aperture-type applicators modifies the actual current distribution in the heating material. Using a two-dimensional finite element method, we have shown that "focusing" is possible such that the SAR at the center of a phantom can be adjusted to be approximately twice that in superficial regions, even though the wavelength is considerably greater than the dimensions of the phantom.