October 11, 1976

Tumor Eradication by Radiofrequency Therapy-Reply

Author Affiliations

Veterans Administration Hospital Brooklyn, NY

JAMA. 1976;236(15):1691. doi:10.1001/jama.1976.03270160014008

Radiofrequency (RF) heating of tissue can be accomplished in two ways. That referred to by Dr Selker is inductive heating, wherein the RF current is converted into a magnetic field by passing it through a coil. The magnetic field induces heat in conductive materials such as electrolyte solutions, metal particles, and wires. Naturally, even temperature sensors with high resistance wires would be heated above ambient temperature and thus interfere with measurements. Our work was done with the other method of RF heating, called dielectric heating.

This is accomplished by placing the part to be heated between two plates of a condenser. The current passing between the two electrodes heats only poorly conductive substances and does not heat wires. Nevertheless, the RF current can traverse the wires into the indicating circuits. This is prevented by the interposition of a small, commercially available RF filter. The accuracy of such temperature