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降低B0/B1 + 灵敏度在速度选择性逆转动脉旋转标记中,使用附带重定焦脉冲进行标记
Divya S Bolar1,2, Ryan A Barnes1,2, Conan Chen1,2,3
1Center for Functional MRI, University of California San Diego, La Jolla, California, USA.
Magnetic resonance in medicine
|July 16, 2024
概括
在速度选择性反转 (VSI) 脉冲列车中,亚底动重定焦显著减少了速度选择性动脉旋转标记 (VSASL) perfusion 成像中的器件. 这种方法提高了图像质量,并为复杂的相循环技术提供了替代方案.
科学领域:
- 磁共振成像是一种磁共振成像技术.
- 生物医学工程 生物医学工程
- 神经成像是一种神经成像.
背景情况:
- 速度选择性动脉旋转标记 (VSASL) 对于非侵入性输液成像至关重要.
- 速度选择性反转 (VSI) 脉冲列车对磁场不均质 (B0/B1+) 非常敏感.
- 当前的VSI技术往往需要复杂的动态相循环 (DPC) 来减轻工件.
研究的目的:
- 为了实现VSASL的VSI脉冲列车中的adiabatic重定位.
- 为了降低基于VSI的 perfusion 成像中的B0/B1+灵敏度和人工物.
- 为了使用单对标签控制减法实现无工件成像,避免DPC.
主要方法:
- 引入一个富里埃变换VSI (FT-VSI) 列车,配有附带的过度波形断面重定焦对.
- 将FT-VSI与标准复合重定焦列车进行比较,有或没有DPC.
- 评估模拟的速度选择性配置文件,幻影研究和人类受试者成像,以评估文物和灰色物质 perfusion异质性.
主要成果:
- 阿迪亚巴特重定位显著提高了FT-VSI对B0/B1+不均性的稳定性.
- 与非DPC复合重定位相比,在模拟和幻影中显著提高了减法准确度.
- 消除人类受试者的工件,导致灰质 perfusion 不同质性的减少.
结论:
- 一个新的VSASL标签列车,利用VSI的亚亚巴特重定位,有效地将文物最小化.
- 这种方法为DPC提供了可行的替代方案,克服了它的局限性.
- 这种新方法提高了VSASL perfusion成像的应用性和可靠性.
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