Present and future status of noninvasive selective deep heating using RF in hyperthermia

Abstract

To achieve hyperthermia using electromagnetic energy, RF of under 100 MHz is basically suitable for the external heating of the deep portions of the body. For applicators using such RF, the following types are considered: capacitive, inductive, radiative and hybrid. With radiative applicators, the intensity of the EM waves radiated from the applicator decreases with propagation into the material to be heated, but the phased annular array of radiative applicators potentially increases the intensity of the EM energy in the deep portion owing to the interference of the waves. Using this method, the focusing of EM energy depends on the dielectric properties of the material to be heated. With respect to RF heating at a lower frequency than the RF used for the annular phased array, some devices have been said to concentrate EM energy in the deep portions, where the characteristics of 'wave' are not utilised. To this end, some methods using capacitive electrodes, an inductive coil, or a combination of both, are being designed. The results of using such methods have shown that it is possible to supply sufficient EM energy to the muscle layers deep in the material to be heated, without heating the fat layers excessively.

Multi-functional magnetic nanoparticles for magnetic resonance imaging and cancer therapy

“…The deficiency of hyperthermic cancer treatment is due to the difficulty of raising the tissue temperature properly [58]. Hyperthermia using magnetic nanoparticles can raise the temperature in the tumor locally up to 41–45 °C and is capable of damaging the tumor cells without damaging the healthy cells [59].…”

Fem Modeling for Performance Evaluation of an Electromagnetic Oncology Deep Hyperthermia Applicator When Using Monopole, Inverted T, and Plate Antennas

“…Some waveguides used as hyperthermia applicators are the ridged waveguides, [6] the AMC-4 array [7] and the two tilted waveguide [8]; however, all of them are fed by monopole antennas [1,[6][7][8]. There are performance studies of monopoles proposed for ISM-band applications, which have been used in the design of feeders for microwave antennas [9,10].…”

Size dependent heat generation of magnetite nanoparticles under AC magnetic field for cancer therapy

“…Hyperthermic cancer treatments have been used for many years, particularly in anticancer therapy [ 1 ]. However, efficiency of the treatment did not satisfy in the clinical scene, because of its difficulty of raising the objective tissue temperature properly [ 2 ]. There Magnetic Fluid Hyperthermia (MFH), by using the magnetite (Fe 3 O 4 ) as a preferable heating source, due to its strong magnetic property and low toxicity, is a promising approach for treating cancer [ 3 ].…”