非对称旋回回声多回声平面成像 (ASEME-EPI) 序列用于临床前高场fMRI
Kyle A Johnson1, Christopher P Pawela1,2,3, Andrew S Nencka2
1Department of Biomedical Engineering, Medical College of Wisconsin, Wauwatosa, WI, United States of America.
bioRxiv : the preprint server for biology
|October 17, 2024
概括
一种新的成像技术,非对称旋转回声多回声平面成像 (ASEME-EPI),通过结合灵敏度和特异性来增强临床前功能性MRI (fMRI). 这种方法改善了脑成像中的信号恢复和定位,克服了现有方法的局限性.
科学领域:
- 神经成像是一种神经成像.
- 磁共振成像 (MRI) 是一种磁共振成像技术.
背景情况:
- 在fMRI中,渐变回忆回声 (GRE) 采集具有高灵敏度,但容易导致信号损失,缺乏微血管特异性.
- 旋转回声 (SE) 采集提供了更好的特异性,但以降低灵敏度的代价.
- 高场临床前fMRI面临着敏感性诱导的信号损失和T2*衰变的挑战.
研究的目的:
- 为高场临床前fMRI引入和评估非对称旋转回声多回声平面成像 (ASEME-EPI).
- 结合GRE和SE技术的好处,以提高fMRI性能.
- 评估ASEME-EPI在具有挑战性的成像条件下提高特异性和信号恢复的能力.
主要方法:
- 开发并实施ASEME-EPI,使用一个自旋回声读取,其次是两个不对称的自旋回声GRE读取.
- 在北方树中使用视觉刺激对9.4T临床前MRI系统进行了可行性研究.
- 将ASEME-EPI与传统的GRE回声平面成像 (GRE-EPI) 和SE回声平面成像 (SE-EPI) 进行比较.
主要成果:
- ASEME-EPI实现了与GRE-EPI可比的BOLD对比度与噪声比率 (CNR).
- ASEME-EPI在激活图表中表现出更好的特异性,将活动局限于主要视觉皮层 (V1).
- 该技术成功地恢复了在GRE-EPI失败的严重现场不均质区域的信号.
结论:
- 在高场临床前fMRI中,ASEME-EPI提供了GRE灵敏度和SE特异性之间的有希望的妥协.
- 多回声性质和最初的SE读数有助于无声化和信号恢复.
- ASEME-EPI显示了克服T2*衰变挑战和在临床前神经成像中改善局部化的潜力.
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