Research On The Equivalent Mannequin Of Bone-tumor Tissue And The Development Of Microwave Bone-tumor Therapeutic Device

Presently, using interstitial microwave hyperthermia has become a new method to treat deep bone-tumor. The therapy combined radiotherapy and chemotherapy is proved to have a good clinical effect. According to postoperative following-up, the recurrence rate is also very low. Especially for those early and intermediate bone-tumor patients, most of them are able to recover normal limbs and trunks function after therapy. But there still exist a lot of shortcomings in the therapy, which limit its further development. There are two main reasons: One is the microwave heat distribution. We can't learn truly heat absorption distribution among the tumor tissues, for we know little about electromagnetism parameters of different bone-tumor tissue. During operation clinicians only depend on experience to heat, which may lead to over-heating or insufficient heating. Over-heating can cause normal tissue near the bone-tumor to be damaged and affect postoperative functional recovery, while insufficient heating may result in some bone-tumor tissues still alive and lead to recurrence. So an ideal heating method would not be realized before clinicians know exactly about the heat distribution among bone-tumor tissues. The method should include the way of inserting microwave antenna array, heating time and optimum heating temperature. We think, lacking of an ideal heating method is a key factor which influences hyperthermia. The other reason is the limitation of therapeutic device. At present, there is no specialized device aimed at interstitial microwave bone-tumor hyperthermia, for the device requires great power together with high quality temperature measure system. In fact, the therapeutic device clinically used now is early laboratory product. Its microwave source is aging and its temperature measure system can't realize real-time temperature measuring during operation. Therefore, it is necessary to develop a new-type microwave therapeutic device adapting to the new technology. According to above-mentioned practical requirements, I am engaged in following researches: I) Under the direct of electromagnetism theory, looking for the measure solution of dielectric constant of common bone-tumor tissues; 2) Processing living bone-tumor specimen and preparing samples for test; 3) Using measure system of simulation six-port reflectometer to measure the samples in order to acquire their dielectric constants; 4) Referring to medicinal formulas of equivalent microwave mannequin commonly used at home and abroad, then mixing a different new-type mannequin through experiments; 5) Using measure system to get the dielectric constant of equivalent microwave bone-tumor tissues; 6) Comparing the two results, then changing the medicinal formulas of equivalent microwave mannequin in order to make their constants same or similar to practical constants; 7) In accordance to the requirement of clinical operation, developing a new-type microwave bone-tumor therapeutic device. During my studying of postgraduate, I accomplished above-mentioned researches and results are listed below: 1) Found a solution to measure the dielectric constant of bone-tumor tissues and equivalent microwave mannequin, the solution is to use the measure system of simulation six-port reflectometer which is originally used for the industry and now used to measure electromagnetism parameters of biological tissues. The experimental results show that the solution can meet the needs of the experimentations. 2) Improved the common medicinal formulas of equivalen...