基于Snake改进模型的心脏MR图像左心室分割方法  

A Segmentation Method of Left Ventricle in Cardiac Magnetic Resonance Images Based on Improved Snake Model

作　　者：朱敏[1] 张炜雪 曲全民 李梦颖[1] 高丽峰[1] 

机构地区：[1]四川大学计算机学院,四川成都610065 [2]东北大学信息科学与工程学院,辽宁沈阳110004

出　　处：《四川大学学报（工程科学版）》2015年第2期82-88,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(61103137)

摘　　要：提出一种基于Snake改进模型的心脏MR图像左心室分割方法。首先对梯度矢量流GVF模型进行改进,提出基于扩展邻域的S型函数梯度矢量流ENSGVF模型,该模型可获得更大的捕获域,并能解决深度凹陷及弱边界泄露的问题。然后将ENSGVF作为新的外力条件,构造ENSGVF Snake模型,用于内外膜分割。对于内膜分割,引入圆形约束项,消除由于图像灰度不均匀造成的局部极小问题。进而利用内膜分割结果构造新的外力场和约束,实现外膜的精确自动分割。实验结果表明,该算法能有效解决分割中存在的弱边界、图像灰度不均匀、乳突肌干扰等问题,提高了精确度。A novel method for segmenting cardiac magnetic resonance images based on Snake model was proposed. An external force called extended neighborhood Sigmoid gradient vector flow ENSGVF was presented as the improvement of gradient vector flow( GVF)for Snake which has a good performance on deep and narrow concavity convergence,capture range and weak edge preserving. In terms of the segmentation of endocardium,and considering that the left ventricle is roughly a circle,a circle shape constraint was adopted on the basis of ENSGVF Snake models,which can eliminate the unexpected local minimum caused by image inhomogeneity and papillary muscle. For the segmentation of epicardium,making full use of the segmentation result of endocardium,a new external force field and a new shape constraint were constructed to achieve automatic precise segmentation. The experimental results showed that the proposed method can address the challenges of lake of edge inhomogeneity,image inhomogeneity,effect of papillary muscle,and improves the rate of accuracy.

关 键 词：心脏MR图像 SNAKE模型 ENSGVF模型 形状约束 图像分割 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]