Numerical Simulation Of Temperature Field Distribution In Magnetic Induction Hyperthermia

Tumor is a type of diseases with high morbidity rate,and the malignant tumor,conventionally called cancer,is one of the most deadly diseases in the world.Although the traditional tumor treatments such as surgery,radiotherapy and chemotherapy have certain curative effects,they will cause pain to the patients due to the poor tolerance.Radiotherapy and chemotherapy will have side effects.Magnetic induction hyperthermia is a safe and efficient tumor physical therapy method using magnetic medium to generate heat upon the application of external magnetic field to kill the tumors.In this thesis,the effective therapeutic volumes and temperature field distributions of single and multi-point injections of magnetic fluid are analyzed with the finite element method(FEM).Single injection means single thermal source.The effective therapeutic volume and the maximum temperature are discussed based on thermal source size and strength.When the total dose of the magnetic material is the same,the larger the thermal source size is,the smaller the thermal source strength.Considering the toxicity of the magnetic fluid in the human body and the effective therapeutic volumes bing formed in the range of 42—48?,the reasonable thermal source size and strength are obtained in this study.Multi-injections mean multi-thermal sources.The effective therapeutic volume and the temperature field distribution along the diametrical of the center section at different thermal source distances are discussed based on different numbers of thermal sources.When the thermal source size and thermal intensity are all the same and there is no over-heated volume(more than 48?)in tumor tissue,the effective therapeutic volume decreases with the increase of the thermal source distance.The effective therapeutic volume is not a simple sum of the individual thermal sources,and it exhibits a strongly nonlinear increase with the increasing numbers of thermal sources.The temperature field distribution can predict whether there is any over-heated or under-heated volume in tumor.The reasonable arrangement of magnetic thermal sources,and the prediction of temperature field distribution can provide the guidance for clinical applications.