The Use of Conductive Thermoplastic Wires as Oxygen Sensors in Microwave Fields
Local microwave induced hyperthermia is considered standard treatment in the management of maligant disease, specifically recommended for locally recurrent tumors and for primary cancer where other treatment modalities have a poor history of success Several mechanisms of action of heat on tumors have been determined including, among others, vascular damage which disturbs the already poor tumor blood supply resulting in increased heat retention and deprivation of oxygen and nutrition in tumors (2-10) leading to a decrease in tissue pH and tumor death. In previous publications we have described the possible prognostic value of clinically determining PO2 levels during hyperthermia treatments to predict the effectiveness of the given therapy (3), however, when measurements are to be made in strong electromagnetic or microwave fields such as occur during hyperthermic treatment of cancerous tumors, the metallic nature of the sensing electrodes cause the formation of electrical eddy currents that induce self heating of the sensors leading to erreous readings and can also induce thermal burns on the treated tissues.
KeywordsMicrowave Field Hyperthermia Treatment Thermal Burn Metallic Nature Bunsen Flame
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