具PH導向聚焦特性微小型腫瘤高溫療法電極系統之開發研究

The research and development of hyperthermia therapy with micro-electrode system and guideline of pH focusing character

王聖宏(Sheng-Hung Wang)

指導教授 ： 王唯工

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.02024

摘要

循環系統疾病一直是已開發國家的主要死因，而惡性腫瘤名列十大死因之首。本研究主要在開發研究具pH導向聚焦特性微小型腫瘤高溫療法電極系統，可針對低pH值腫瘤組織進行選擇性的熱療，以協助其他治療方法之不足。並可對於因灌流不足的血循環障礙的組織，進行局部組織的加溫，促進血循環灌流量。

本研究希望發展一套新的腫瘤高溫治療系統，藉由腫瘤細胞因缺氧而比正常細胞低pH值的特性，與組織中低pH值有較低阻抗值的特性 [32]，配合電學基本原理，以解決一般熱療方式所面臨的問題：在無精準的判定分辨正常與腫瘤細胞情況下，高解析度的聚焦的實用性受到限制。本文在第三章中我們提出整個系統的架構方塊圖與其實現的方法，並藉由波型產生器、電極將一定電壓加在仿體上，找出影響系統效率的原因與參數，包括電極材料的選擇、系統電極架構、電極與仿體或目標物間的匹配問題與頻率的影響。其中，我們發現不鏽鋼材質為較佳的電極材料，非對稱電極架構有較好的加熱效果，而在較高的頻率會有較好的聚焦效果，這些都可提供未來實現此系統的重要依據。為了達成在有活體循環散熱的效果下仍能達到攝氏41度的加熱且範圍可以超過針狀電極附近1立方公分大小的初步的目標，在第四章中，我們評估了熱場分佈，並改善實驗環境與非對稱電極架構後，以多針狀電極在攝氏37度恆溫封閉空間中，可將目標物加熱至攝氏41度且對低pH部份有更好的聚焦效果。

本研究已完成整個系統定性的部份，證實其臨床上實現的可行性，並找出影響系統效率的原因與參數，包括電極材料的選擇、系統電極架構、電極與仿體或目標物間的匹配問題與頻率的影響。這些結論都可提供未來發展此系統的重要依據。

關鍵字

熱療 ； 癌症治療

並列摘要

Circulatory diseases have long been the main causes of mortality in developed countries and also the cancer is the first causes of mortality. The study is to research and develop the hyperthermia therapy micro-electrode system which could focus on the low pH location. The system can make up the defect of other therapy by heating the low pH cancer tissue selectively. The system also can promote the perfusion by heating local tissue to those poor circulation tissues.

In this study we feel like to develop a new hyperthermia therapy system. Through the characters which are the lower pH quality in cancer cell, due to the lack of oxygen, also the low resistance in cancer cell [32], with combination of the basic electric theory. In chapter three, we bring up the system’s block diagram and the method of realization. We find out that the parameters and the causes of the influence in system including the choice of electrode, the structure of system, the matching problems between electrode and the target, and the frequency by using function generator and electrodes to apply a specific voltage to phantom. Among these parameters, we find out that the stainless steel is the better electrode material, and the asymmetric structure has better heating effect, and also with higher frequency we have better focusing effect. Such important basis can help us to realize the system as well. To achieve the first goal that could heat the phantom to 41 degrees centigrade with the range of 1 cube centimeters around the needle electrode in the circulating environment in vivo. In chapter four, we evaluate the distribution of the thermal field and improve the experimental environment, and the asymmetric structure. We achieve to heat the temperature to 41 degrees centigrade with multi-electrode in the closed space at constant temperature 37 degrees centigrade and have the batter effect on focusing on low pH area.

In this study, we have done the qualitative analysis of the system. We prove the feasible to use in clinic and find the parameters and the causes of the influence in system including the choice of electrode, the structure of system, the matching problems between electrode and the target, and also the frequency. Therefore, we believe those important basis will help us to develop these system perfect in the future world.

並列關鍵字

hyperthermia therapy ； cancer therapy

參考文獻

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