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在7T的超短TE STEAM MR光谱中观察到的宏分子共振与年龄相关的差异
Guglielmo Genovese1, Melissa Terpstra1, Pavel Filip1,2
1Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA.
Magnetic resonance in medicine
|March 5, 2024
概括
人类大脑的宏分子含量随着年龄的增长而变化. 特定的宏分子峰值从中年开始显著增加,而其他峰值则在晚些时候上升,突出了对年龄相匹配量化的需要.
科学领域:
- 神经成像是一种神经成像.
- 生物化学 生物化学
- 人类的衰老 人类的衰老
背景情况:
- 人类大脑中的宏分子含量对于理解组织组成至关重要.
- 大脑生化学的与年龄相关的变化还没有得到充分的描述.
- 活体磁共振光谱 (MRS) 提供了一种非侵入性方法来评估大脑代谢物.
研究的目的:
- 为了研究健康的人类大脑中的宏分子含量与年龄相关的变化.
- 使用先进的MRS技术量化宏分子共振.
- 建立不同年龄组的宏分子含量规范数据.
主要方法:
- 在体内采集1H-MR光谱使用超短TE STEAM在7T后带状皮层中采集.
- 分析了来自19-89岁健康群体的147个数据集.
- 使用三个不同的配合方法评估宏分子含量,包括新型模型和LCModel模拟的宏分子.
主要成果:
- 在大约1.7 ppm (MM17) 和2.0 ppm (MM20) 的宏分子峰值中,观察到与年龄相关的中度至强度的影响.
- 显著更高的MM17和MM20含量出现在30-40岁之间.
- 在0.9,1.2和1.4ppm的峰值中,与年龄相关的增长较弱,从60-70岁观察到的显著上升.
结论:
- 年龄显著影响人类大脑中特定的宏分子共振的内容.
- 对于整个寿命的不同宏分子峰值,存在着不同的变化模式.
- 准确量化大脑宏分子含量需要使用年龄匹配的参考数据.
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