Liu Xiuxiu, Du Lei, Zhang Bing, Zhao Zifang, Gao Wenwen, Liu Bing, Liu Jian, Chen Yue, Wang Yige, Yu Hongwei, Ma Guolin
Department of Radiology, China-Japan Friendship Hospital, Beijing, China.
Graduate School of Peking Union Medical College, Beijing, China.
Front Neurosci. 2021 Feb 16;15:616163. doi: 10.3389/fnins.2021.616163. eCollection 2021.
This study adopted diffusion tensor imaging to detect alterations in the diffusion parameters of the white matter fiber in Alzheimer's disease (AD) and used quantitative susceptibility mapping to detect changes in magnetic susceptibility. However, whether the changes of susceptibility values due to excessive iron in the basal ganglia have correlations with the alterations of the diffusion properties of the white matter in patients with AD are still unknown. We aim to investigate the correlations among magnetic susceptibility values of the basal ganglia, diffusion indexes of the white matter, and cognitive function in patients with AD. Thirty patients with AD and nineteen healthy controls (HCs) were recruited. Diffusion indexes of the whole brain were detected using tract-based spatial statistics. The caudate nucleus, putamen, and globus pallidus were selected as regions of interest, and their magnetic susceptibility values were measured. Compared with HCs, patients with AD showed that there were significantly increased axial diffusivity (AxD) in the internal capsule, superior corona radiata (SCR), and right anterior corona radiata (ACR); increased radial diffusivity (RD) in the right anterior limb of the internal capsule, ACR, and genu of the corpus callosum (GCC); and decreased fractional anisotropy (FA) in the right ACR and GCC. The alterations of RD values, FA values, and susceptibility values of the right caudate nucleus in patients with AD were correlated with cognitive scores. Besides, AxD values in the right internal capsule, ACR, and SCR were positively correlated with the magnetic susceptibility values of the right caudate nucleus in patients with AD. Our findings revealed that the magnetic susceptibility of the caudate nucleus may be an MRI-based biomarker of the cognitive dysfunction of AD and abnormal excessive iron distribution in the basal ganglia had adverse effects on the diffusion properties of the white matter.
本研究采用扩散张量成像检测阿尔茨海默病（AD）患者白质纤维扩散参数的变化，并使用定量磁化率映射检测磁化率的变化。然而，基底节中铁过量导致的磁化率值变化与AD患者白质扩散特性的改变是否相关仍不清楚。我们旨在研究AD患者基底节的磁化率值、白质扩散指数和认知功能之间的相关性。招募了30例AD患者和19名健康对照者（HCs）。使用基于纤维束的空间统计学检测全脑的扩散指数。选择尾状核、壳核和苍白球作为感兴趣区，并测量其磁化率值。与HCs相比，AD患者在内囊、放射冠上部（SCR）和右侧放射冠前部（ACR）的轴向扩散率（AxD）显著增加；右侧内囊前肢、ACR和胼胝体膝部（GCC）的径向扩散率（RD）增加；右侧ACR和GCC的各向异性分数（FA）降低。AD患者右侧尾状核的RD值、FA值和磁化率值的改变与认知评分相关。此外，AD患者右侧内囊、ACR和SCR的AxD值与右侧尾状核的磁化率值呈正相关。我们的研究结果表明，尾状核的磁化率可能是基于MRI的AD认知功能障碍生物标志物，基底节中铁分布异常过量对白质的扩散特性有不利影响。
