Age effects and sex differences in human brain white matter of young to middle-aged adults: A DTI, NODDI, and q-space study.
Age effects and sex differences in human brain white matter of young to middle-aged adults: A DTI, NODDI, and q-space study.
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DOI：
10.1016/j.neuroimage.2015.12.033
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发表时间：
2016-03
期刊：
影响因子：
5.7
通讯作者：
Wu YC
中科院分区：
文献类型：
--
作者：
Kodiweera C;Alexander AL;Harezlak J;McAllister TW;Wu YC
应用先进扩散磁共振成像技术（dMRI）研究了中青年脑白质的微结构变化。使用混合扩散成像（HYDI）获得多个壳层扩散加权数据。HYDI方法非常通用，数据分析使用扩散张量成像（DTI）、神经突定向弥散和密度成像（NODDI）和q空间成像方法。本研究包括24名女性和23名男性，年龄在18至55岁之间。年龄和性别对扩散指标的影响在全脑48个感兴趣的白质区域（roi）中使用最小二乘线性回归进行了测试，并对roi之间的多重比较进行了调整。在这项研究中，白质投射到海马体或大脑皮层是对衰老最敏感的大脑区域。具体来说，在这个年轻到中年的队列中，衰老效应与白质纤维的更多分散有关，而组织限制和轴突内体积分数保持相对稳定。NODDI纤维弥散指数对老化的敏感性最为显著。此外，该衰老队列中DTI指数的变化主要与纤维弥散指数相关，而与细胞内NODDI体积分数或q空间测量无关。虽然男性和女性在衰老率上没有差异，但男性的轴突内体积分数往往高于女性。这项研究表明，使用HDYI采集和NODDI的室室建模的高级dMRI可以阐明对年龄和性别敏感的微结构改变。最后，本研究揭示了DTI扩散指标与NODDI模型高级扩散指标与q空间成像之间的关系。
Microstructural changes in human brain white matter of young to middle-aged adults were studied using advanced diffusion Magnetic Resonance Imaging (dMRI). Multiple shell diffusion-weighted data were acquired using the Hybrid Diffusion Imaging (HYDI). The HYDI method is extremely versatile and data were analyzed using Diffusion Tensor Imaging (DTI), Neurite Orientation Dispersion and Density Imaging (NODDI), and q-space imaging approaches. Twenty-four females and 23 males between 18 and 55 years of age were included in this study. The impact of age and sex on diffusion metrics were tested using least squares linear regressions in 48 white matter regions of interest (ROIs) across the whole brain and adjusted for multiple comparisons across ROIs. In this study, white matter projections to either the hippocampus or the cerebral cortices were the brain regions most sensitive to aging. Specifically, in this young to middle-aged cohort, aging effects were associated with more dispersion of white matter fibers while the tissue restriction and intra-axonal volume fraction remained relatively stable. The fiber dispersion index of NODDI exhibited the most pronounced sensitivity to aging. In addition, changes of the DTI indices in this aging cohort were correlated mostly with the fiber dispersion index rather than the intracellular volume fraction of NODDI or the q-space measurements. While men and women did not differ in the aging rate, men tend to have higher intra-axonal volume fraction than women. This study demonstrates that advanced dMRI using a HDYI acquisition and compartmental modeling of NODDI can elucidate microstructural alterations that are sensitive to age and sex. Finally, this study provides insight into the relationships between DTI diffusion metrics and advanced diffusion metrics of NODDI model and q-space imaging.