We present data from localized heat inducement studies at both cellular and tissue levels along with a computational model built to predict the temperature increase and damage extent in tissues receiving hyperthermia treatment by a fiber-based active heater. This novel fiber-based active heater serves as a heat source and a temperature sensor. Five important insights are highlighted from this thesis work.
First, heat-induced controlled cell deaths were observed experimentally in the three cell lines with MCF-10A being more susceptible to heat compared to HEK 293 and MCF7 cells. Second, comparison between the phantom tissue and ex vivo experimental and computational results shows a lesion size of 5×12 mm and 4.87×11.6 mm in the phantom tissue and 7×15 mm and 8.8×14.3 mm in the ex vivo studies at pumping power of 1.8 W for 10 minutes respectively. Thus, this computational model is able to provide information about the heat transfer characteristics caused by the active heater in living biological tissue.
Third, under similar conditions of pumping power and heating time to that used in the ex vivo experiment, we found that the blood perfusion has a profound effect on the amount of induced heat at the active heater surface (or at the heat source). Because of the small dimension of lethal volume, heat dissipation by blood with a volumetric perfusion rate of 6.4×10-3 Kg/m3s in the liver tissues is very small.
Forth, in all the experimental and computational studies, hyperthermia position and damage extent can be controlled by the active heater through managing the temperature increase and the power supply during heating, thereby avoiding the transient effect of heat outside of the target volume. Thus, this hybrid simulation/active heater approach may have the potential to provide reliable temperature increase information before and during a procedure in which controlled localized heating is required.
Finally, we show that when packaged, the fiber-based active heater does not suffer from a significant reduction in heating efficiency. Hyperthermia-induced lesions by the packaged active heater were in order of 3.9×14.5 mm and 3.787×5.24 mm.