INVERSE HEAT TRANSFER ANALYSIS OF MICRO HEATER STRENGTH AND LOCATIONS FOR HYPERTHERMIA TREATMENT OF BRAIN TUMORS

摘要

In this study the strength and location of micro heat source terms are found with extra constraints in order to obtain a unique solution. In hyperthermia the use of a sequence of high intensity pulses separated by power-off intervals causes temperature fluctuations and consequently it is not possible to maintain a constant temperature which is the ultimate goal of hyperthermia. However, it is generally agreed that the effectiveness of thermal treatment depends on the cumulative effect of elevated temperatures over the treatment time [5]. To this end a thermal dose concept is used to quantify the relationship between treatment efficiencyand target temperature as a function of time. As a result, in the inverse problem instead of using measured temperatures we use a desired thermal dose and try to match the computed dose to the desired one. Our goal is then to find the locations and the strengths of the heat sources which gives us the desired thermal dose. We choose the desired a thermal dose in the x domain, which minimizes the thermal dose in the surrounding tissue. Another constrain could be the total delivered power by the microheaters. Since the microheaters are running with battery, we would like to find a solution that requires minimal power input to microheaters.