Complementary displacement-encoded MRI for contrast-enhanced infarct detection and quantification of myocardial function in mice
Complementary displacement-encoded MRI for contrast-enhanced infarct detection and quantification of myocardial function in mice
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DOI：
10.1002/mrm.20003
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发表时间：
2004-04-01
影响因子：
3.3
通讯作者：
Epstein, FH
中科院分区：
文献类型：
--
作者：
Gilson, WD;Yang, ZQ;Epstein, FH
MRI 正在成为评估心血管疾病（包括心肌梗塞 (MI)）转基因和基因敲除小鼠模型心肌功能的重要方式。受激回波位移编码 (DENSE) 使用相位重建图像以高空间分辨率测量心肌运动。当前的 DENSE 技术使用反转恢复 (IR) 来抑制 T-1 弛豫伪影；然而，IR 不适合心脏中的对比增强梗塞成像，因为在心脏中会观察到多个 T-1 值。我们开发了一种改进的 DENSE 方法，采用互补采集来抑制与 T-1 无关的伪影。通过这种技术，可以在相位重建图像中测量位移和应变，并在完美配准的幅度重建图像中描绘梗塞的对比度增强区域。使用旋转模型验证了位移测量和 T-1 加权图像对比度。在 MI 之前和之后对小鼠 (N = 9) 进行改良的 DENSE。测量周向（E-cc）和径向（E-rr）应变，并通过DENSE检测对比增强的梗塞心肌。基线时，E-cc 为 -0.16 +/- 0.01，E-rr 为 0.39 +/- 0.07。 MI后，梗塞区域的E-cc为0.04+/-0.02，E-rr为0.03+/-0.04，而非梗塞区域的E-cc为-0.12+/-0.02，E-rr为0.38+/-0.09。通过 DENSE 测定的体内 E-cc 与通过常规标签分析获得的 E. 相关性良好 (R = 0.90)。 (C) 2004 Wiley-Liss, Inc.
MRI is emerging as an important modality for assessing myocardial function in transgenic and knockout mouse models of cardiovascular disease, including myocardial infarction (MI). Displacement encoding with stimulated echoes (DENSE) measures myocardial motion at high spatial resolution using phase-reconstructed images. The current DENSE technique uses inversion recovery (IR) to suppress T-1-relaxation artifacts; however, IR is ill-suited for contrast-enhanced infarct imaging in the heart, where multiple T-1 values are observed. We have developed a modified DENSE method employing complementary acquisitions for T-1-independent artifact suppression. With this technique, displacement and strain are measured in phase-reconstructed images, and contrast-enhanced regions of infarction are depicted in perfectly coregistered magnitude-reconstructed images. The displacement measurements and T-1-weighted image contrast were validated with the use of a rotating phantom. Modified DENSE was performed in mice (N = 9) before and after MI. Circumferential (E-cc) and radial (E-rr) strain were measured, and contrast-enhanced infarcted myocardium was detected by DENSE. At baseline, E-cc was -0.16 +/- 0.01 and E-rr was 0.39 +/- 0.07. After MI, E-cc was 0.04 +/- 0.02 and E-rr was 0.03 +/- 0.04 in infarcted regions, whereas E-cc was -0.12 +/- 0.02 and E-rr was 0.38 +/- 0.09 in noninfarcted regions. In vivo E-cc as determined by DENSE correlated well with E., obtained by conventional tag analysis (R = 0.90). (C) 2004 Wiley-Liss, Inc.