The biological effects for the use of hyperthermia to treat malignant tumors has been well studied and encouraging clinical results have been reported. However, the engineering and technical aspects of hyperthermia for the deep-seated tumors has not been satisfactory. We have developed the RF capacitive hyperthermia device (Greenytherm-GY 8) by cooperation with Yonsei Cancer Center and Green Cross Medical Corporation. It was composed with 8~10 MHz RF generator, capacitive electrode, matching system, cooling system, temperature measuring thermocouples and control PC computer. We, have measured the temperature and thermal distribution in agar phantom, animals and human tumors. This RF hyperthermia device could be applied for clinical trials as result of following studies.
1) The generating power could be varied to 700~1500 W
2) The Radio-frequency for capacitive heating could be produced to 8~10 MHz
3) It was possible to control the depth heating from skin by regulation the cooling temperature of bolus and choosing properly size electrodes.
4) Deep seated tumors (5~10 cm depth) might be heated to therapeutic temperature 40~43℃.
5) Side effects and hot feeling on skin could be significantly reduced by cooling bolus and electric matching.
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