提高体内欧米茄图表交换参数的标准化和准确性,使用基于旋转框架模型的准稳定状态Z光谱的配合
Julius Juhyun Chung1, Hahnsung Kim1,2, Yang Ji3
1Primate Imaging Center, Emory National Primate Research Center, Emory University, Atlanta, Georgia, USA.
Magnetic resonance in medicine
|September 2, 2024
概括
准稳态 (QUASS) 重建标准化了体内胺基交换量化. 基于模型的QUASS Z-spectra配件提供了准确的胺参数,改进了化学交换和转移 (CEST) 成像的多洛伦茨方法.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 生物物理化学 生物物理化学
- 神经成像是一种神经成像.
背景情况:
- 在体内胺交换性质的 Ω 图形驱动量化已经确立,但对扫描参数变化敏感.
- 标准化是必要的,以确保可靠的确定胺交换在不同的收购条件.
研究的目的:
- 评估准平稳状态 (QUASS) Z光谱重建,以标准化体内胺基交换量化.
- 在体内使用化学交换和转移 (CEST) 成像来确定QUASS重建的准确性.
主要方法:
- 模拟和体内动物大脑CEST数据在4.7T时被分析.
- 数据采用多洛伦茨和基于模型的方法,与或没有QUASS重建.
- 在体内和模拟中,通过全球性缺血 (心脏骤停) 诱导pH调节.
主要成果:
- 模拟表明,多洛伦茨拟合低估了汇率,错误远离稳定状态条件.
- 基于模型的装配与QUASS重建估计的汇率,在模拟中<2%的误差.
- 在体内,多劳伦斯合产生了64 ± 13秒-1 (38 ± 16秒-1 后缺血症),而基于QUASS模型的合产生了126 ± 25秒-1 (49 ± 13秒-1 后缺血症).
结论:
- 基于模型的QUASS CEST Z光谱的装配使得胺交换参数的一致和准确量化成为可能.
- QUASS重建可以减少信号重叠和非平衡 CEST 效应的错误,从而改善 Ω 图形分析.
- 这种方法提高了体内胺基交换测量的可靠性.
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