Haggerty Christopher M, Kramer Sage P, Skrinjar Oskar, Binkley Cassi M, Powell David K, Mattingly Andrea C, Epstein Frederick H, Fornwalt Brandon K
University of Kentucky, Departments of Pediatrics, Physiology and Medicine, Lexington, Kentucky, USA.
J Magn Reson Imaging. 2014 Aug;40(2):398-406. doi: 10.1002/jmri.24350. Epub 2013 Oct 29.
To test the hypothesis that magnitude images from cine displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI) can accurately quantify left ventricular (LV) volumes, mass, and ejection fraction (EF).
Thirteen mice (C57BL/6J) were imaged using a 7T ClinScan MRI. A short-axis stack of cine T2-weighted black blood (BB) images was acquired for calculation of LV volumes, mass, and EF using the gold standard sum-of-slices methodology. DENSE images were acquired during the same imaging session in three short-axis (basal, mid, apical) and two long-axis orientations. A custom surface fitting algorithm was applied to epicardial and endocardial borders from the DENSE magnitude images to calculate volumes, mass, and EF. Agreement between the DENSE-derived measures and BB-derived measures was assessed via coefficient of variation (CoV).
3D surface reconstruction was completed on the order of seconds from segmented images, and required fewer slices to be segmented. Volumes, mass, and EF from DENSE-derived surfaces matched well with BB data (CoVs ≤11%).
LV mass, volumes, and EF in mice can be quantified through sparse (five slices) sampling with DENSE. This consolidation significantly reduces the time required to assess both mass/volume-based measures of cardiac function and advanced cardiac mechanics.
验证以下假设，即采用激励回波位移编码（DENSE）磁共振成像（MRI）获得的幅度图像能够准确量化左心室（LV）容积、质量和射血分数（EF）。
使用7T ClinScan MRI对13只C57BL/6J小鼠进行成像。采集 cine T2加权黑血（BB）图像的短轴堆栈，采用金标准切片求和法计算LV容积、质量和EF。在同一成像过程中，以三个短轴（基底、中部、心尖）和两个长轴方向采集DENSE图像。应用自定义表面拟合算法，根据DENSE幅度图像的心外膜和心内膜边界计算容积、质量和EF。通过变异系数（CoV）评估DENSE衍生测量值与BB衍生测量值之间的一致性。
从分割图像中以秒为单位完成3D表面重建，且分割所需的切片数量更少。DENSE衍生表面的容积、质量和EF与BB数据匹配良好（CoV≤11%）。
小鼠的LV质量、容积和EF可通过DENSE的稀疏（五片）采样进行量化。这一整合显著减少了评估基于质量/容积的心脏功能测量值和先进心脏力学所需的时间。
