Resonant circuits for hyperthermia excited by RF magnetic field of MRI

The hyperthermia using a magnetic resonance imaging (MRI) is proposed. A resonant circuit consisting of a closed connection of coil and capacitor was used as an implant heated by an external ac magnetic field. Its resonant frequency was 63.9 MHz. The maximum temperature rise of 40/spl deg/C was obtained from the thermally insulated resonant circuit by applying the field of 0.034 Oe with continuous wave. The rf magnetic field of the MRI with a low duty factor could raise the circuit temperature up to 13/spl deg/C. This therapeutic method enables a repeated combination of the hyperthermia treatment and MRI diagnosis by confirming the operated effect.