Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
Department of Pathology and Laboratory Medicine, The Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
Neuroimage Clin. 2020;27:102340. doi: 10.1016/j.nicl.2020.102340. Epub 2020 Jul 6.
White matter hyperintensities (WMH) occur in normal aging and across diagnostic categories of neurodegeneration. Ultra-high field imaging (UHF) MRI machines offer the potential to improve our understanding of WMH. Post-mortem imaging using UHF magnetic resonance imaging (MRI) is a useful way of assessing WMH, however, the responsiveness of UHF-MRI to pathological changes within the white matter has not been characterized. In this study we report post-mortem MRI sequences of white matter hyperintensities in normal aging, Alzheimer's disease, and cerebrovascular disease. Seven Tesla post-mortem MRI reliably detected periventricular WMH using both FLAIR and T2 sequences and reflects underlying pathology of myelin and axon density despite prolonged fixation time. Co-registration of histological images to MRI allowed for direct voxel- wise comparison of imaging findings and pathological changes. Myelin content and cerebrovascular pathology were the most significant predictors of MRI white matter intensity as revealed by linear mixed models. Future work investigating the utility of UHF- MRI in studying cell-specific changes within WMH is required to better understand radio-pathologic correlations.
脑白质高信号（WMH）可见于正常衰老及各种神经退行性疾病。超高场磁共振成像（UHF MRI）有望提高我们对 WMH 的认识。超高场 MRI 后尸体成像可用于评估 WMH，但尚未明确 UHF-MRI 对脑白质内病理改变的反应性。在这项研究中，我们报告了正常衰老、阿尔茨海默病和脑血管病的脑白质高信号的超高场 MRI 后尸体序列。7T 超高场 MRI 后尸体成像序列，使用 FLAIR 和 T2 序列可靠地检测到脑室周围 WMH，并反映了髓鞘和轴突密度的潜在病理学，尽管固定时间延长。将组织学图像与 MRI 配准，允许对成像发现和病理改变进行直接体素比较。线性混合模型显示，髓鞘含量和脑血管病理是 MRI 脑白质强度的最显著预测因子。需要进一步研究超高场 MRI 在研究 WMH 内细胞特异性变化中的应用，以更好地理解放射病理学相关性。
