臺灣博碩士論文加值系統

心肌細胞外容積比(extracellular volume fraction, ECV)是計算單位體積中心肌細胞外體積所佔有的比例，其量化計算有助於偵測心肌纖維化程度，目前來說，可使用磁共振影像(magnetic resonance imaging, MRI)或電腦斷層掃描(computed tomography, CT)搭配各自顯影劑進行ECV的定量。本論文將分析CT及MRI兩種影像ECV數值的相關性，以及利用CT影像開發一套ECV mapping的使用者介面。

在分析CT及MRI兩者影像的ECV值，首先將CT的正向橫切面轉置成MRI的短軸切面，並針對基部、中層、與心尖位置三張切面各自圈選四個心肌區域計算ECV值，並探討兩種醫學影像的ECV值的相關性。從10組受試者的結果中顯示MRI與CT所量測的ECV具有中度相關性(R=0.42)，此外，分區的相關性分析顯示在受試者心室側壁所量測到的ECV相關性較高(R=0.73)，一致性區間也較小(-3.4%~11.7%)低，可能是因為該處與肺臟相鄰，其輪廓具有較佳的對比。

此外，本研究的另一個主題是以處理CT影像為主開發一套計算ECV mapping的GUI介面，採用的影像處理流程包含影像對位、影像分割、ECV 計算、以及ECV視覺化表示等四個主要步驟。此套GUI介面的開發目的是提供醫護人員處理臨床資料後能立即顯示，在操作GUI介面時，會有功能視窗告知使用者目前執行階段及參數設定以及提醒使用者後續的步驟。GUI介面的設計概念是以最少的參數設定及最簡易的流程步驟開發，並且能將操作區各個步驟的影像處理結果於顯示區顯示，方便使用者觀察。

Extracellular volume (ECV) fraction of myocardium is the volumetric ratio of extracellular space to the myocardial volume. Measurement of ECV fraction is helpful on the diagnosis of myocardial fibrosis. So far, the non-invasive quantification of ECV can be performed by either using magnetic resonance imaging (MRI) or computed tomography (CT) with the administration of contrast agent for each imaging technique. There are two purposes of the thesis: the first is to compare the ECV values measured by CT and MRI respectively. The second is to develop a graphical user interface (GUI) of ECV mapping with the use of CT data set.

Before comparing the ECV values obtained by CT and MRI respectively, the three-dimensional CT volume has to be reformatted to the short-axis view to imitate the MR acquisition. Four regions of interest on ventricular myocardium are manually selected on each of the base, middle, and apical planes. Therefore, the ECV fractions measured by using CT and MRI , respectively, are compared to examine the correlation. Results of 10 patients show moderately correlated (R=0.42). Regional analysis demonstrates that the correlation of two medical imaging techniques obtained at the lateral ventricle wall is obviously higher (R=0.73) with comparatively limited 95% interval of agreement (-3.4%~11.7%), which is probably due to the clear outer contour of myocardium in contrast with pulmonary space.

Another theme of this study is to establish a GUI to obtain ECV mapping using CT. The image processing method of this study is consisted of four major parts, including image registration, tissue segmentation, ECV calculation and 3D visualization. This GUI is developed to provide medical staff with immediate processing to clinical data without extensive labor in programming. During the use of this GUI, a display window would provide information about the current execution phase, parameter settings, and the subsequent step for the user. The design concept of the GUI is to complete the ECV mapping with minimal parameter settings and the reduced processing steps. In addition, the results of each step are shown on the display panel for better observation.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 vi
圖目錄 viii
表目錄 xi
第一章 簡介 1
1.1 心肌細胞外容積比介紹與臨床應用 1
1.2 研究目的 5
第二章 研究方法 7
2.1 ECV公式介紹 7
2.1.1 CT ECV公式介紹 7
2.1.2 MRI ECV公式介紹 9
2.2 影像資料 10
2.3 MRI ECV研究方法及流程 13
2.3.1 MRI量測ECV流程(有原始影像) 14
2.3.2 MRI量測ECV流程(無原始影像) 15
2.4 CT ECV研究方法及流程 16
2.4.1 CT掃描切面轉置 18
2.4.2 CT短軸切面對位 21
2.5 MRI與CT相關性比較 22
第三章 結果與分析 23
3.1 CT短軸切面結果 23
3.2 CT及MRI量測的ECV結果 26
3.3 MRI與CT相關性分析 32
第四章 CT影像開發ECV mapping GUI介面 35
4.1 GUI架構及功能介紹 35
4.2 GUI操作流程與結果展示 38
4.2.1 讀檔 38
4.2.2 影像對位 39
4.2.3 影像分割及ECV mapping 42
4.2.4 ECV視覺化顯示 44
4.2.5 GUI介面其他 45
第五章 討論與結論 46
5.1 兩種醫學影像計算ECV的相關性 46
5.2 心肌影像分割討論 49
5.3 GUI 時間討論及優劣勢 50
5.4 結論 52
參考文獻 53

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