Voltin Joshua, Nunn Lisa M, Watson Zoe, Brasher Zoe E, Adisetiyo Vitria, Hanlon Colleen A, Nietert Paul J, McRae-Clark Aimee L, Jensen Jens H
Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina, USA.
Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA.
NMR Biomed. 2024 Mar;37(3):e5072. doi: 10.1002/nbm.5072. Epub 2023 Nov 27.
Several magnetic resonance imaging (MRI) measures for quantifying endogenous nonheme brain iron have been proposed. These correspond to distinct physical properties with varying sensitivities and specificities to iron. Moreover, they may depend not only on tissue iron concentration, but also on the intravoxel spatial pattern of iron deposition, which is complex in many brain regions. Here, the three MRI brain iron measures of , magnetic field correlation (MFC), and magnetic susceptibility are compared in several deep gray matter regions for both healthy participants (HPs) and individuals with cocaine use disorder (CUD). Their concordance is assessed from their correlations with each other and their relative dependencies on age. In addition, associations between the iron measures and microstructure in adjacent white matter regions are investigated by calculating their correlations with diffusion MRI measures from the internal capsule, and associations with cognition are determined by using results from a battery of standardized tests relevant to CUD. It is found that all three iron measures are strongly correlated with each other for the considered gray matter regions, but with correlation coefficients substantially less than one indicating important differences. The age dependencies of all three measures are qualitatively similar in most regions, except for the red nucleus, where the susceptibility has a significantly stronger correlation with age than . Weak to moderate correlations are seen for the iron measures with several of the diffusion and cognitive measures, with the strongest correlations being obtained for . The iron measures differ little between the HP and CUD groups, although susceptibility is significantly lower in the red nucleus for the CUD group. For the comparisons made, the iron measures behave similarly in most respects, but with notable quantitative differences. It is suggested that these differences may be, in part, attributable to a higher sensitivity to the spatial pattern of iron deposition for and MFC than for susceptibility. This is supported most strongly by a sharp contrast between the values of the iron measures in the globus pallidus relative to those in the red nucleus. The observed correlations of the iron measures with diffusion and cognitive scores point to possible connections between gray matter iron, white matter microstructure, and cognition.
已经提出了几种用于量化内源性非血红素脑铁的磁共振成像（MRI）测量方法。这些方法对应于对铁具有不同敏感性和特异性的不同物理特性。此外，它们可能不仅取决于组织铁浓度，还取决于铁沉积的体素内空间模式，而这在许多脑区都很复杂。在此，对健康参与者（HP）和可卡因使用障碍（CUD）个体的几个深部灰质区域中的三种MRI脑铁测量方法，即[具体方法1]、磁场相关性（MFC）和磁化率进行了比较。通过它们之间的相互相关性以及它们对年龄的相对依赖性来评估它们的一致性。此外，通过计算它们与来自内囊的扩散MRI测量值的相关性，研究了铁测量值与相邻白质区域微观结构之间的关联，并使用一系列与CUD相关的标准化测试结果来确定与认知的关联。结果发现，对于所考虑的灰质区域，所有三种铁测量方法彼此之间都有很强的相关性，但相关系数远小于1，这表明存在重要差异。除了红核外，在大多数区域，所有三种测量方法对年龄的依赖性在定性上是相似的，在红核中，磁化率与年龄的相关性明显强于[具体方法1]。铁测量值与几种扩散和认知测量值之间存在弱到中等的相关性，其中[具体方法1]的相关性最强。HP组和CUD组之间的铁测量值差异不大，尽管CUD组红核中的磁化率明显较低。对于所做的比较，铁测量值在大多数方面表现相似，但存在明显的定量差异。有人认为，这些差异可能部分归因于[具体方法1]和MFC对铁沉积空间模式的敏感性高于磁化率。苍白球中铁测量值与红核中铁测量值之间的鲜明对比最有力地支持了这一点。观察到的铁测量值与扩散和认知分数之间的相关性表明灰质铁、白质微观结构和认知之间可能存在联系。
