基于MRI图像的主动脉弓变形测量方法的研究

目的:准确测量主动脉弓的变形和位移,以便于主动脉弓血流动力学的仿真计算以及主动脉弓疾病的形态学诊断的进行。方法:本文首先基于主动轮廓模型(GVFSnakes模型)把MRI图像中的主动脉部分与胸腔分割开来,之后对人主动脉弓一个心动周期内的多幅MRI图像进行分析,建立主动脉弓运动的动态模型,并通过相关软件对主动脉弓的变形情况进行测量。结果:获得了一个行动周期内升主动脉根部,升主动脉中部,头臂动脉分支前,左锁骨下动脉分支后以及降主动脉中部等五个典型截面的变形量。结论:升主动脉中段的边界变形幅度较大,其他部分截面面积变化相对较平稳。通过对主动脉弓MRI图像的分析研究,可以准确地获取到血管边界的位移和变形信息。

Measurement of Aortic Arch Deformation Based on MRI Images

Objective:To measure the deformation of aortic arch accurately, so as to solve the hemodynamic simulated computation of aortic arch and the morphological diagnosis of aortic arch diseases. Method:The aorta image is segmented from the thorax image firstly based on the active contour model (GVF Snakes), the MRI images of human aortic arch in one single cardiac cycle are analyzed and a dynamic model of the motive aortic arch is developed for the deformation measurement. Result:The deformation data of the representative sections, including the root of ascending artery, the middle of the ascending artery, the section before the brachial artery, the section after the left subclavian artery and the middle of the descending artery, are obtained in one cardiac cycle. Conclusion:The range of the deformation of the ascend aorta is larger than the other section. The deformation, as well as the displacement of the vessel wall of the aorta can be obtained from the MRI image analysis.