USING TLM METHOD TO MODEL HYPERTHERMIA APPLICATORS

Hugo A. Dominguez, Adroaldo Raizer

Abstract


The Transmission Line Matrix (TLM) method is used to study a noninvasive two-dimensional electric-type hyperthermia applicator. The electric field distribution and the specific absorption rate (SAR) pattern are calculated and graphically displayed for several design variations, showing the fundamental limitation of this kind of applicator: overheating of the fat by normal strong components of electric field. One example of applicator designed to avoid fat overheating is described: a 100 MHz dipole with thick water bolus, utilized for treatment of small tumors at 4-5 cm muscle depth. The results show that the TLM technique is well suited to be used as a tool for designing more efficient stimulation procedures.

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References


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