左心室心肌容量的異常與許多心血臟疾病息息相關，因此左心室容量是一個用來診斷心血管疾病的重要參考。為了協助醫師與放射線師評估心室的容積，本研究提出一個在延遲相電腦斷層影像自動找出左心室的心肌輪廓並且計算其容積方法。由於相鄰的影像有一定的相似性。因此、切割出第一張Leading slice後，即可用此結果切割相鄰的影像。首先利用動脈相的輪廓、mean shift與門檻值找出大致上的心肌區域，接著利用區域成長與凸包(convex hull)演算法來找出心內膜區域，最後使用形態學與心肌寬度大致相同的這個特性，找出心外膜並且計算其心肌容積，如此便可以得到Leading slice的結果。再使用Leading slice切割相鄰影像，並將結果與兩位熟練專家所描繪的輪廓進行比較，實驗結果證實此系統可得到相當高的相似度(similarity index, SI)，此方法可以用於自動描繪出心肌輪廓，並且計算其面積。 Many cardiac diseases are related to volume of cardiac left ventricle (LV). Thus volume of cardiac LV is important information to diagnose ischemic heart diseases. In order to assist radiologists and physicians to estimate the LV volume, this study proposed an automatic segmentation method to contour the myocardial region in delayed phase of multi-detector row computed tomography (MDCT) imaging and then compute the volume of cardiac LV myocardium. The proposed method performs roughly myocardium base on threshold and contour that contour from artery phase. The endocardium would obtain after the methods that region growing, Convex-hull was used. Finally, the width similar properties within myocardial region and the morphology operators are used to obtain the whole LV myocardial volume. Compared with the contours manually delineated by two experienced experts, the automatic contouring results from computer simulation reveal that the proposed method always identifies similar contours as that obtained by the manual sketching.
