title: Heating system with a lens applicator for 430 MHz microwave hyperthermia.
abstract: To attain deep and localized heating for hyperthermic treatment of cancers, metal plate lens applicators that can converge microwave electromagnetic (EM) energy in the lossy medium such as human muscle with a computer-controlled heating system have been developed. This paper describes a system operating at 430 MHz. Results of an electric-field distribution calculation and a heating experiment made on a saline solution phantom show that the maximum heating depth is over 60 mm using the lens applicator, which is twice as deep as that obtained with a conventional waveguide applicator. The experimental results agree well with the theoretical ones. A computer-controlled heating system has been developed using the applicator. Experimental results show that fluctuations in temperature at locations in the heating region of the saline phantom were maintained within +/- 0.3 degrees C of the present temperatures. These results indicate that the system can be used for the clinical hyperthermia treatment of cancer.
authors.affiliation: Department of Electrical Engineering, National Defense Academy, Yokosuka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Nikawa
authors.forename: M
authors.initials: M
authors.lastname: Kikuchi
authors.forename: T
authors.initials: T
authors.lastname: Terakawa
authors.forename: T
authors.initials: T
authors.lastname: Matsuda
mesh_terms: D001698:Biomedical Engineering; D004574:Electromagnetic Fields; D006358:Hot Temperature / Q000627:therapeutic use*; D006801:Humans; D008838:Microcomputers; D008872:Microwaves / Q000627:therapeutic use*; D008953:Models, Anatomic; D009369:Neoplasms / Q000628:therapy; D013696:Temperature