Zhong Jia, Liu Wei, Yu Xin
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
J Magn Reson Imaging. 2008 Jun;27(6):1263-70. doi: 10.1002/jmri.21367.
To develop a 3D MR tagging method that combines harmonic phase (HARP) and homogeneous strain analysis methods for quantification of regional myocardial wall motion in mice.
3D tagged images were acquired from seven C57BL/6 mice. Intersecting tag points were reconstructed and 3D strains were quantified at apical, midventricular, and basal levels. Circumferential and radial strains quantified with 2D MR tagging were compared with those calculated from 3D tagged images.
Our data showed significant heterogeneity in radial, circumferential, and shear strains. Longitudinal strain was more homogeneous. The circumferential-longitudinal shear strain, a unitless measure of ventricular torsion, was positive throughout the left ventricle. There were strong correlations between 2D and 3D studies at the basal and midventricular levels.
This work demonstrates the feasibility of 3D characterization of cardiac function in mouse via the combination of HARP and homogeneous strain analysis.
开发一种结合谐波相位（HARP）和均匀应变分析方法的三维磁共振标记方法，用于量化小鼠局部心肌壁运动。
从7只C57BL/6小鼠获取三维标记图像。重建相交的标记点，并在心尖、心室中部和基部水平量化三维应变。将二维磁共振标记量化的圆周应变和径向应变与从三维标记图像计算得到的应变进行比较。
我们的数据显示径向、圆周和剪切应变存在显著异质性。纵向应变更均匀。圆周-纵向剪切应变是心室扭转的无量纲度量，在整个左心室中均为正值。在基部和心室中部水平，二维和三维研究之间存在强相关性。
这项工作证明了通过结合HARP和均匀应变分析对小鼠心脏功能进行三维表征的可行性。
