结合水平集方法和形状约束Snake模型的左心室MRI图像分割  

Left Ventricle MRI Images Segmentation by Unifying Level Set Method and Snake Model with Shape Constraints

作　　者：周则明[1] 尤建洁[2] 范春晖[1] 王平安[3] 夏德深[2] 

机构地区：[1]解放军理工大学气象学院,南京211101 [2]南京理工大学计算机系,南京210094 [3]香港中文大学计算机科学与工程系

出　　处：《模式识别与人工智能》2006年第6期782-786,共5页Pattern Recognition and Artificial Intelligence

基　　金：香港特区政府研究资助局资助项目(No.CUHK/4180/01E.CUHK1/00C)

摘　　要：提出结合水平集方法和形状约束Snake模型的左心室MRI图像分割算法。由于左心室存在弱边缘、与周围的组织之间存在低对比度区域,Snake模型分割左心室MRI图像时,将会出现变形曲线泄漏现象,通过对训练图像的配准、变化模式的分析,定义左心室的边界形状变化允许空间,根据心脏MRI图像的特点,使用水平集方法在平均形状周围构造形状约束能量场,在Snake模型中增加形状约束能量项后,能够有效处理变形曲线的泄漏问题,通过将演化曲线投影到形状允许空间,对其施加形状约束,心脏MRI图像的分割实验证明了模型的有效性。A segmentation algorithm for the left ventricle MRI images is proposed by unifying the level set method and the snake model with shape constraints . Due to the weak edges and the low contrast regions, the deformation curve leaks from the outer boundary of the left ventricle when the snake model is used to segment the MRI image of the left ventricle. After the training samples have been aligned and the variation modes have been analyzed, the allowable shape space of the left ventricle is constructed. According to the properties of the cardiac MRI images, the shape constraint energy field around the average shape is created by the level set method. After the shape constraint energy term is added, the snake model can effectively prevent the deformation curve from leaking out of the low contrast regions. The evolving curve is subject to the shape constraints by mapping it to the allowable shape space. The segmentation experiments demonstrate the effectiveness of the proposed model.

关 键 词：SNAKE模型 水平集方法 形状约束能量 左心室分割 MRI图像 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]