动态B0场闪用于改善7T的伪连续动脉旋转标记
Yang Ji1,2, Joseph G Woods1, Hongwei Li1,3
1Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
Magnetic resonance in medicine
|December 6, 2024
概括
一种新的动态B0闪方法通过纠正大脑动脉中的磁场变化来改善7T的伪连续动脉旋转标记 (PCASL). 这提高了标签效率和 perfusion 信号恢复,以获得更好的成像.
科学领域:
- 磁共振成像是一种磁共振成像技术.
- 神经成像是一种神经成像.
- 生物医学工程 生物医学工程
背景情况:
- 在7特斯拉 (7T) 的B0场异质性通过降低标记效率和 perfusion 信号,显著损害了伪连续动脉旋转标记 (PCASL).
- 这种人工物特别明显出现在大脑养动脉中,需要有针对性的纠正策略.
研究的目的:
- 为7T PCASL.开发和评估特定于船舶的动态B0场闪方法.
- 其目标是提高标记效率,并减轻动脉内非共振效应引起的信号损失.
主要方法:
- 实施了7T PCASL序列,包括动态B0闪,以纠正大脑养动脉中的B0场偏移.
- 利用快速获取的,船舶特定的B0场地图来计算RF脉冲的动态闪参数.
- 对全球频率偏移和最佳编码方案校正进行了二维和三维变体的评估,量化脑血流 (CBF) 变化.
主要成果:
- 所有经过测试的非共振校正方法都成功地恢复了脑 perfusion 信号.
- 拟议的船舶特定的动态B0闪方法提高了标签的效率,并保持了最佳的静态闪.
- 3D动态B0闪闪发光的变体表现出高于全球和2D方法的性能,显著增加了量化的CBF值.
结论:
- 开发的动态B0闪方法代表了7T PCASL的重大进步.
- 这种技术提高了PCASL的稳定性和有效性,使7T ASL的高灵敏度和空间分辨率能够更好地利用.
关键词:
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