超音波影像工具，由於具有非侵入式、對人體無害、檢測費用便宜、儀器價格較便宜、能即時成像以及機動性高等優點，目前已經是醫學上不可或缺的診斷工具，但由於傳統灰階影像必須藉由專業的醫師，來解讀所得到的超音波影像，且灰階影像並無法用來做定量分析，因此為了能夠提供更客觀的判斷方式，在後來才有學者提出許多統計模性，來做定量分析。也有學者針對在發生病變時組織特性的改變，而發展出不同的功能性影像。各種不同的影像技術發展，都是為了能夠做更準確且更有效的診斷。
而本研究則是使用到三種影像技術，分別是B-mode影像、Nakagami影像以及彈性影像，在研究的第一部分，主要是利用仿體實驗，來驗證Nakagami統計參數所代表的物理意義，分別設計了四種不同的仿體，再配合Nakagami影像以及彈性影像來做驗證。
第二部份豬肉組織燒灼實驗，則是鑒於近年來燒灼治療已經是醫學上一項常用的治療技術，但燒灼治療過程中往往無法由肉眼來判斷出治療部位，因此必須藉由其他影像工具的輔助，而在本實驗中，利用對豬肉組織做燒灼，再分別使用B-mode影像、Nakagami影像以及彈性影像作燒灼面積的計算，B-mode影像以及Nakagami影像利用燒灼後組織特性變化，配合影像處理來圈選出燒灼區域，彈性影像則是觀察壓縮過程影像變化來圈選出燒灼區域，目的是找出最佳的影像工具來輔助燒灼治療。

The ultrasound diagnostic imaging has become one of the most used tool in medical examination, since it has the advantages of non-invasive, harmless, low price, real-time and high mobility properties. However, because of ultrasound B-mode image need to be construed by instructed doctor and can not be used to quantitative analysis, many statistical models were proposed in order to provide more objective diagnostic. Besides, some functional ultrasound images were also developed for pathological changes of tissue.
In this study, we utilized three different functional ultrasound images: B-mode image, Nakagami image and elasticity image. In the first part, we used phantom experiment to verify the Nakagami m parameter’s physical mean. We design four different phantom ,and verify Nakagami m parameter with Nakagami imaging and elasticity imaging.
The second part of study is tissue ablation experiment. In recent year, ablation technique has been a common treatment technology. However, it is not easy to find out the affected part with bare eyes during ablation therapy, therefore some imaging tools have been carried out. In this study, we ablated pork tissue by microwave ablation technique, then we used B-mode image, Nakagami image and elasticity image to observe the change of tissue and evaluate the area of tissue ablation in order to find out the suitable imaging tool to aid in ablation.

致謝 I
中文摘要 III
Abstract V
目錄 VII
圖目錄 XI
表目錄 XV
第一章 緒論 1
1.1前言 1
1.2研究背景 3
1.3文獻回顧 4
1.3.1超音波逆散射訊號統計模型 4
1.3.2彈性影像發展 7
1.4研究目的 10
第二章 理論基礎 13
2.1超音波原理及簡介 13
2.1.1超音波基本原理 13
2.1.2超音波之反射與折射 16
2.1.3超音波之衰減 18
2.1.4 超音波換能器與聲場 19
2.2超音波逆散射分析 23
2.2.1散射現象 23
2.2.2單一散射子 23
2.2.3多散射子 26
2.3超音波之逆散射訊號統計模型 28
2.3.1 Rayleigh統計分佈 28
2.3.2 Rician統計分佈 29
2.3.3 K統計分佈 30
2.3.4 Nakagami統計分佈 31
2.4彈性影像成像原理及方法 33
2.4.1 彈性影像發展背景 33
2.4.2 彈性影像成像原理 34
第三章 實驗材料與方法 39
3.1超音波掃描系統 39
3.1.1系統架構 39
3.1.2掃描方式 42
3.2仿體實驗 43
3.2.1仿體製作方式 43
3.2.2仿體掃描步驟 44
3.3豬肉燒灼實驗 47
3.4實驗數據處理 48
第四章 實驗結果與討論 53
4.1仿體實驗 53
4.2彈性模數量測 63
4.3豬肉燒灼實驗 67
4.3.1豬肉燒灼結果 67
4.3.2 燒灼面積計算 81
第五章 結論與展望 93
5.1 結論 93
5.1.1 仿體實驗結論 93
5.1.2 燒灼實驗結論 93
5.2未來展望 95
參考文獻 97

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