現代人罹患癌症的情況已經相當常見，各界都積極努力地尋求預防或治療癌症的方法。消極的作法是藉由藥物來控制癌細胞擴散的速度，積極方面則是藉由放射線治療法清除體內癌細胞。而本研究最主要的目標是從現有的放射線醫療器材進行改善創新，設計一套能夠應用在臨床上的醫療工具。

放射線治療法可細分成體內以及體外的治療方式，當中體外放射線治療法會使用呼吸調節法(respiratory gating method)輔助放射線治療。應用呼吸調節法的關鍵在於呼吸作用會造成腹腔體表產生明顯起伏的影響，而體內器官以及組織也會連帶產生移動的現象，如此一來要正確地定位出腫瘤位置難度更高。因此針對呼吸調節法之醫療輔助器材的設計，目的是製作出能產生近似呼吸運動的機構，以及可具有生物擬真性的人體模型。

因此本研究希望利用致動器來控制呼吸的頻率以及深度，以及使用複合材料製作具有生物擬真性的人體模型。其中致動器部分主要是由伺服馬達驅動凸輪機構所組成，人體模型則由放在機台上模擬呼吸的狀態。整個假體模型機構架設完後，便能夠利用實驗找出體表特徵點與體內腫瘤間運動的相關性。

Nowadays, there are more and more people getting cancer, so it is a need to find ways to prevent or cure this disease. We can use medicine to suppress the cancer passively, or use radiotherapy to kill the cancer actively. In this research, one set of medical equipment is proposed to assist the radiation treatment.

Radiotherapy can be divided into internal and external treatment, and the external treatment uses respiratory gating method to assist radiotherapy. The key point of applying respiratory gating method is to downplay the influences caused by respiratory motion and the motion of internal organs and tissue. These influences normally make it harder to locate tumor position and conduct the radiation treatment. In order to increase the clinical effect, the proposed device in this research has to reproduce respiratory motion like a human being. Therefore, one of the objectives of this thesis is to develop medical assisted equipment which is capable of duplicating respiratory motion and its effect for the tumor motion during treatment.

This research will utilize an actuator to control the frequency and amplitude of respiratory motion, and make a bio-fidelity human model by composite materials. The actuator is mainly composed of a servo-motor and a cam mechanism; the bio-fidelity human model is placed on the stage to simulate the respiratory motion. When the phantom mechanism is set, it is possible to find out the correlation between markers and tumors.

摘要 I
Abstract II
誌謝 III
目錄 IV
表目錄 VI
圖目錄 VII
符號說明 IX
第一章 緒論 1
1.1. 前言 1
1.2. 研究目的與動機 3
1.3. 文獻回顧 5
1.4. 論文架構 7
第二章 理論基礎 9
2.1. 電腦斷層掃描 9
2.1.1 放射線治療之標靶體積 10
2.1.2 Hounsfield Unit 12
2.2. 呼吸調節法 13
2.2.1. RPM系統 14
2.2.2. 呼吸運動與體外特徵點的關係 15
2.3. 現有假體相關醫療器材介紹 16
2.3.1 產生呼吸運動之機構 16
2.3.2 假體之構造 18
第三章 研究方法 19
3.1 設計流程 19
3.2 呼吸運動 20
3.2.1 呼吸波形 20
3.2.2 深度與頻率 22
3.3 電腦斷層掃描之限制 22
3.4 假體尺寸 22
3.5 假體力學性質之量測方法 23
第四章 設計細節 24
4.1. 機台設計 24
4.1.1 凸輪外形設計 25
4.1.2 假體幾何外形 27
4.1.3 假體外殼設計 27
4.1.4 假體材料 28
4.2. 伺服馬達介紹 29
4.3. 人體腹腔內器官之力學性質 31
4.4. 人體座標定義 33
第五章 模擬結果 36
5.1 模型建立 36
5.1.1. 假體幾何外形與參數設定 36
5.1.2. 假體內部腫瘤標示物位置 38
5.2 確認設計需求 39
5.2.1. 凸輪轉速 39
5.2.2. 從動件位移 40
5.3 腫瘤及體表特徵點位移 40
5.3.1. 定義腫瘤及特徵點座標 41
5.3.2. 腫瘤位移 43
5.3.3. 特徵點位移 45
第六章 實驗結果 48
6.1 設計需求之確認 48
6.1.1 凸輪轉速 49
6.1.2 從動件位移 49
6.2 腫瘤與特徵點位移 51
6.2.1 體表特徵點位移 51
6.2.2 利用電腦斷層掃描分析腫瘤位移 58
第七章 結果與討論 62
7.1 結果與討論 62
7.1.1. 實作與模擬結果比較 62
7.1.2. 腫瘤與特徵點之關聯性 63
7.2 本文貢獻 73
7.3 未來工作 73
參考文獻 74
附錄A 假體機構元件 76
A1. 產生呼吸運動機構之元件設計圖: 76
A2. 呼吸機構元件圖: 80
附錄B 腫瘤位移之模擬結果 81
自述 83

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