MR心脏序列图像左心室内外壁联合分割和时序追踪新方法

MR心脏图像左心室内外壁的自动分割是计算机辅助心功能诊断的前提。本文提出了一种MR心脏图像的左心室内外壁的联合分割和时序追踪的新方法。首先用改进几何动态轮廓线算法分割一帧3维MR图像中的左心室内壁,然后通过时序追踪得到同一层面各帧的内壁轮廓。分割外壁时,以内壁为初始轮廓,设计一种由距离和区域灰度均值约束的区域膨胀力,分割心室的外壁。在临床实际心电门控动态4D心脏MRI序列图像上的实验结果表明,算法分割左心室的内外壁的结果和专家手动分割结果很接近;并且根据心室内外壁分割结果建立的左心室3维模型,可以计算出几种重要的临床心功能指标。

A New Associated Scheme for Segmentation and Tracking of Endocardium and Epicardium from MR Cardiac Image Sequences

Segmentation of endocardium and epicardium from MR cardiac mage sequences is the most important prerequisite for computer aided cardiac function analysis. This paper proposes a new associated scheme for segmentation of endocardium and epicardium from MR cardiac image sequences. Firstly, segment the endocardium improved GACM, then propagate the segmented contour to other time frames. Secondly, using the segmented endocardium as the initialization contour, the curve is evolved with ad hoc designed regional balloon force controlled by the local mean gray level and the distance from endocardium to get epicardium. Experimental results on clinical ECG gated 4-D cardiac MR images are very close to the outlines medical experts manually. Left ventricle surface model can be reconstructed based on the segmentation results and some important clinical cardiac indices can be calculated.