Department of Radiological Sciences, Diagnostic Cardiovascular Imaging Section, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
J Cardiovasc Magn Reson. 2010 Jun 1;12(1):33. doi: 10.1186/1532-429X-12-33.
Displacement encoded Cardiovascular MR (CMR) can provide high spatial resolution measurements of three-dimensional (3D) Lagrangian displacement. Spatial gradients of the Lagrangian displacement field are used to measure regional myocardial strain. In general, adjacent parallel slices are needed in order to calculate the spatial gradient in the through-slice direction. This necessitates the acquisition of additional data and prolongs the scan time. The goal of this study is to define an analytic solution that supports the reconstruction of the out-of-plane components of the Lagrangian strain tensor in addition to the in-plane components from a single-slice displacement CMR dataset with high spatio-temporal resolution. The technique assumes incompressibility of the myocardium as a physical constraint.
The feasibility of the method is demonstrated in a healthy human subject and the results are compared to those of other studies. The proposed method was validated with simulated data and strain estimates from experimentally measured DENSE data, which were compared to the strain calculation from a conventional two-slice acquisition.
This analytical method reduces the need to acquire data from adjacent slices when calculating regional Lagrangian strains and can effectively reduce the long scan time by a factor of two.
位移编码心血管磁共振(CMR)可提供三维(3D)拉格朗日位移的高空间分辨率测量。拉格朗日位移场的空间梯度用于测量局部心肌应变。通常,为了计算切片内方向的空间梯度,需要相邻的平行切片。这需要采集额外的数据并延长扫描时间。本研究的目的是定义一个解析解,该解析解支持从单切片位移 CMR 数据集重建除平面内分量之外的平面外分量,该数据集具有高时空分辨率。该技术假设心肌的不可压缩性是一个物理约束。
该方法在健康人体受试者中证明了其可行性,并将结果与其他研究进行了比较。该方法已通过模拟数据和实验测量的 DENSE 数据的应变估计进行了验证,并与传统的双切片采集的应变计算进行了比较。
当计算局部拉格朗日应变时,该分析方法减少了从相邻切片获取数据的需求,并可有效将扫描时间缩短两倍。