关键词: 左心室, 图像分割, 水平集, 弱边界

Abstract:

The left ventricular MR image segmentation algorithm based on the Distance Regular Level Set model（DRLSE） has a strong dependence on the gradient information, and is easy to fall into the local optimum in the weak edge region of the image, and is sensitive to the selection of the initial contour. In order to reduce the sensitivity of the algorithm to the initial contour and improve its ability to segment the weak edge of the left ventricle image, this paper proposes a left ventricular segmentation algorithm suitable for weak edge information. Based on DRLSE, the segmentation algorithm proposes a new local term based on the proposed coefficient of variation based segmentation model（PSM）. The algorithm relies on gradient and image local information to drive the curve evolution, which reduces the sensitivity of DRLSE to the initial contour. In order to overcome the situation where the DRLSE algorithm causes boundary leakage when dividing the weak boundary of the epicardium, shape constraint is introduced. In order to verify the accuracy of the algorithm segmentation proposed in this paper, based on the database provided by the Imaging Department of the Children’s Hospital of Toronto City, the endocardium is segmented by DRLSE, the Convexity Preserving Level Set model（CPLSE）, U-Net network and the endocardium algorithm of this paper; the epicardium is segmented by DRLSE, introduction of epicardium shape binding DRSLE（DRLSE-shape）, U-Net network and the epicardium algorithm of this paper. The experimental results show that the proposed algorithm is superior to the above algorithm for the left ventricular and adventitia, which can reduce the sensitivity of DRLSE to the initial contour and improve the accuracy of MR image segmentation of the left ventricular weak boundary.

Key words: left ventricle, image segmentation, level set, weak boundary