From the Department of Physical Sciences (A.D.M., R.V., S.-P.H., A.Y.M., L.Z.), Sunnybrook Research Institute, Toronto, Ontario, Canada.
Departments of Medical Imaging (L.Z., R.I.A.).
AJNR Am J Neuroradiol. 2018 Jan;39(1):91-96. doi: 10.3174/ajnr.A5410. Epub 2017 Nov 2.
The spatial correlation between WM and cortical GM disease in multiple sclerosis is controversial and has not been previously assessed with perfusion MR imaging. We sought to determine the nature of association between lobar WM, cortical GM, volume and perfusion.
Nineteen individuals with secondary-progressive multiple sclerosis, 19 with relapsing-remitting multiple sclerosis, and 19 age-matched healthy controls were recruited. Quantitative MR perfusion imaging was used to derive CBF, CBV, and MTT within cortical GM, WM, and T2-hyperintense lesions. A 2-step multivariate linear regression (corrected for age, disease duration, and Expanded Disability Status Scale) was used to assess correlations between perfusion and volume measures in global and lobar normal-appearing WM, cortical GM, and T2-hyperintense lesions. The Bonferroni adjustment was applied as appropriate.
Global cortical GM and WM volume was significantly reduced for each group comparison, except cortical GM volume of those with relapsing-remitting multiple sclerosis versus controls. Global and lobar cortical GM CBF and CBV were reduced in secondary-progressive multiple sclerosis compared with other groups but not for relapsing-remitting multiple sclerosis versus controls. Global and lobar WM CBF and CBV were not significantly different across groups. The distribution of lobar cortical GM and WM volume reduction was disparate, except for the occipital lobes in patients with secondary-progressive multiple sclerosis versus those with relapsing-remitting multiple sclerosis. Moderate associations were identified between lobar cortical GM and lobar normal-appearing WM volume in controls and in the left temporal lobe in relapsing-remitting multiple sclerosis. No significant associations occurred between cortical GM and WM perfusion or volume. Strong correlations were observed between cortical-GM perfusion, normal appearing WM and lesional perfusion, with respect to each global and lobar region within HC, and RRMS and SPMS patients ( ≤ 0.96, < .006 and ≤ 0.738, < .006).
The weak correlation between lobar WM and cortical GM volume loss and perfusion reduction suggests the independent pathophysiology of WM and cortical GM disease.
多发性硬化症患者的 WM 与皮质 GM 之间的空间相关性存在争议，且此前尚未通过灌注磁共振成像进行评估。我们旨在确定脑白质（WM）、皮质 GM、体积和灌注之间关联的性质。
共纳入 19 例继发进展型多发性硬化症患者、19 例复发缓解型多发性硬化症患者和 19 例年龄匹配的健康对照者。采用定量磁共振灌注成像技术，在皮质 GM、WM 和 T2 高信号病变内得出脑血流量（CBF）、脑血容量（CBV）和平均通过时间（MTT）。采用 2 步多元线性回归（校正年龄、疾病持续时间和扩展残疾状况量表）评估在全脑和脑叶正常表现的 WM、皮质 GM 和 T2 高信号病变内，灌注和容量测量之间的相关性。适当应用 Bonferroni 校正。
除复发缓解型多发性硬化症患者的皮质 GM 体积与对照组相比无显著差异外，各组间的全脑皮质 GM 和 WM 体积均显著降低。与其他组相比，继发进展型多发性硬化症患者的全脑和脑叶皮质 GM CBF 和 CBV 降低，但复发缓解型多发性硬化症患者与对照组之间无差异。各组间全脑和脑叶 WM CBF 和 CBV 无显著差异。除了继发进展型多发性硬化症患者的枕叶外，皮质 GM 和 WM 体积减少的脑叶分布存在差异。在对照组和复发缓解型多发性硬化症患者的左侧颞叶中，发现了脑叶皮质 GM 和脑叶正常表现 WM 体积之间的中度关联。皮质 GM 与 WM 灌注或体积之间未发生显著关联。在 HC 和 RRMS 及 SPMS 患者的每个全脑和脑叶区域内，皮质 GM 与正常表现 WM 和病变灌注之间均观察到强相关性（≤0.96，<0.006 和≤0.738，<0.006）。
脑叶 WM 与皮质 GM 体积丢失和灌注减少之间的弱相关性提示 WM 和皮质 GM 疾病具有独立的病理生理学机制。
