Hyperthermia has been a modality to treat cancer for thousands of years. During this time, intensive efforts are concentrated on determining the dose of the proper treatment, but the dominantly in vitro induced cellul...Hyperthermia has been a modality to treat cancer for thousands of years. During this time, intensive efforts are concentrated on determining the dose of the proper treatment, but the dominantly in vitro induced cellular death does not provide enough confidence for the clinical dosing. The cell-death by heat-monotherapy applications in laboratory experiments is difficult to apply in the complementary therapies in clinical applications. The newly developed nanotechnologies offer completely new possibilities in this field as well. Modulated electro-hyperthermia (mEHT, trade-name Oncothermia) is a nanoheating technology that has selective effects on membrane rafts and on the transmembrane proteins. This effect is thermal. The thermal action is in nanoscopic range which makes the phenomenon special. Our objective is to show the dose concept on this emerging method.展开更多
A nonlinear finite-element program was developed to simulate the dynamic evolution of coagulation in tissue considering temperature and thermal-dose dependence of the ultrasound attenuation and blood perfusion rate. T...A nonlinear finite-element program was developed to simulate the dynamic evolution of coagulation in tissue considering temperature and thermal-dose dependence of the ultrasound attenuation and blood perfusion rate. The effects of these dynamic parameters on the lesion formation were investigated in the particular case of ultrasound hepatic ablation with bi-focus intensity pattern. The results of simulations were compared that incorporate dynamic changes of ultrasound attenuation and perfusion and results that neglect these effects. The result shows that thermal-dose-dependent ultrasound attenuation is the dominating factor in the full dynamic model. If the dynamic ultrasound attenuation is ignored, a relatively significant underestimation of the temperature rise appears in the focal plane and the region next to the focal plane, resulting in an underestimation in predicting diameter of coagulation. Higher heating intensity leads to greater underestimation.展开更多
文摘Hyperthermia has been a modality to treat cancer for thousands of years. During this time, intensive efforts are concentrated on determining the dose of the proper treatment, but the dominantly in vitro induced cellular death does not provide enough confidence for the clinical dosing. The cell-death by heat-monotherapy applications in laboratory experiments is difficult to apply in the complementary therapies in clinical applications. The newly developed nanotechnologies offer completely new possibilities in this field as well. Modulated electro-hyperthermia (mEHT, trade-name Oncothermia) is a nanoheating technology that has selective effects on membrane rafts and on the transmembrane proteins. This effect is thermal. The thermal action is in nanoscopic range which makes the phenomenon special. Our objective is to show the dose concept on this emerging method.
基金The National Natural Science Foundation ofChina (No 30500124)Shanghai Key Tech-nologies R&D Program of China ( No05DZ19509)
文摘A nonlinear finite-element program was developed to simulate the dynamic evolution of coagulation in tissue considering temperature and thermal-dose dependence of the ultrasound attenuation and blood perfusion rate. The effects of these dynamic parameters on the lesion formation were investigated in the particular case of ultrasound hepatic ablation with bi-focus intensity pattern. The results of simulations were compared that incorporate dynamic changes of ultrasound attenuation and perfusion and results that neglect these effects. The result shows that thermal-dose-dependent ultrasound attenuation is the dominating factor in the full dynamic model. If the dynamic ultrasound attenuation is ignored, a relatively significant underestimation of the temperature rise appears in the focal plane and the region next to the focal plane, resulting in an underestimation in predicting diameter of coagulation. Higher heating intensity leads to greater underestimation.
