2重しきい値法を用いた超音波心断層像からの心内膜輪郭線自動抽出とその信頼性の検討

概要

論文の詳細を見る
Methods for automatic extraction of left ventricular endocardium in echocardiograms have been proposed, which are required to quantitatively evaluate the functional performance of the left ventricle. In this pa-per, we propose a new automatic extraction method based on double thresholding for echocardiograms, and evaluate the effectiveness and the accuracy. B-mode echocardiograms are first binarized with a threshold determined by the discriminant analysis for the gray level histogram. Then the binary images are contracted n times to remove small regions and to disconnect the region of cardiac cavity from the other false regions. Among the obtained regions which corresponds to the cardiac cavity is selected and dilated 2n times to create a mask which restricts the region of the second thresholding operation. The size and the location of the cardiac cavity in the preceding frame are utilized to select the corresponding region. The masked image of each frame is binarized in the restricted area in the same way as in the first thresholding operation. The evaluation test is carried out using the scatter diagram of radius of contours extracted by two observers and automatic extraction method. These results showed that the accuracy of the extracted contours was favorably compared to the accuracy of manually traced contours.
電気学会の論文
2001-09-01