MRI-based strain and strain rate analysis of left ventricle: a modified hierarchical transformation model.
MRI-based strain and strain rate analysis of left ventricle: a modified hierarchical transformation model.
复制标题
基于 MRI 的左心室应变和应变率分析：改进的分层变换模型
DOI：
10.1186/1475-925x-14-s1-s9
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发表时间：
2015
影响因子：
3.9
通讯作者：
Li ZY
中科院分区：
文献类型：
--
作者：
Gan Y;Chen Q;Zhang S;Ju S;Li ZY
与其他心功能指标（如射血分数和递质早期舒张速度）不同，心肌应变有望捕获由心肌早期疾病引起的细微变化。为了提取左心室（LV）心肌应变和应变率，提出了一种改进的分层变换模型。采用包含左心室全局和局部变形的分层变换模型，通过电影- mri图像配准分析左心室的应变和应变率。引入心内膜和心外膜轮廓信息，将原有的分层配准算法与基于不变特征的迭代最近点算法相结合，提高配准精度。首先通过一名正常志愿者对分层模型进行验证，然后将其应用于两例临床病例（即正常志愿者和糖尿病患者）以评估其各自的功能。基于两个临床案例，通过比较正常志愿者所选择的两个地标的位移场，所提出的方法比原始或未修改的模型表现出更好的性能。同时，对比志愿者和患者的径向应变，可以看出他们在功能上的明显差异。本方法可用于估计一个心动周期内左室心肌应变和应变率，从而定量分析左室运动功能。
Different from other indicators of cardiac function, such as ejection fraction and transmitral early diastolic velocity, myocardial strain is promising to capture subtle alterations that result from early diseases of the myocardium. In order to extract the left ventricle (LV) myocardial strain and strain rate from cardiac cine-MRI, a modified hierarchical transformation model was proposed. A hierarchical transformation model including the global and local LV deformations was employed to analyze the strain and strain rate of the left ventricle by cine-MRI image registration. The endocardial and epicardial contour information was introduced to enhance the registration accuracy by combining the original hierarchical algorithm with an Iterative Closest Points using Invariant Features algorithm. The hierarchical model was validated by a normal volunteer first and then applied to two clinical cases (i.e., the normal volunteer and a diabetic patient) to evaluate their respective function. Based on the two clinical cases, by comparing the displacement fields of two selected landmarks in the normal volunteer, the proposed method showed a better performance than the original or unmodified model. Meanwhile, the comparison of the radial strain between the volunteer and patient demonstrated their apparent functional difference. The present method could be used to estimate the LV myocardial strain and strain rate during a cardiac cycle and thus to quantify the analysis of the LV motion function.