Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, USA.
Hum Brain Mapp. 2024 Jan;45(1):e26532. doi: 10.1002/hbm.26532. Epub 2023 Nov 27.
Cortical gray to white matter signal intensity ratio (GWR) measured from T1-weighted magnetic resonance (MR) images was associated with neurodegeneration and dementia. We characterized topological patterns of GWR during AD pathogenesis and investigated its association with cognitive decline. The study included a cross-sectional dataset and a longitudinal dataset. The cross-sectional dataset included 60 cognitively healthy controls, 61 mild cognitive impairment (MCI), and 63 patients with dementia. The longitudinal dataset included 26 participants who progressed from cognitively normal to dementia and 26 controls that remained cognitively normal. GWR was compared across the cross-sectional groups, adjusted for amyloid PET. The correlation between GWR and cognition performance was also evaluated. The longitudinal dataset was used to investigate GWR alteration during the AD pathogenesis. Dementia with β-amyloid deposition group exhibited the largest area of increased GWR, followed by MCI with β-amyloid deposition, MCI without β-amyloid deposition, and controls. The spatial pattern of GWR-increased regions was not influenced by β-amyloid deposits. Correlation between regional GWR alteration and cognitive decline was only detected among individuals with β-amyloid deposition. GWR showed positive correlation with tau PET in the left supramarginal, lateral occipital gyrus, and right middle frontal cortex. The longitudinal study showed that GWR increased around the fusiform, inferior/superior temporal lobe, and entorhinal cortex in MCI and progressed to larger cortical regions after progression to AD. The spatial pattern of GWR-increased regions was independent of β-amyloid deposits but overlapped with tauopathy. The GWR can serve as a promising biomarker of neurodegeneration in AD.
皮质灰白质信号强度比（GWR）的测量来自 T1 加权磁共振（MR）图像，与神经退行性变和痴呆有关。我们描述了 AD 发病过程中 GWR 的拓扑模式，并研究了其与认知能力下降的关系。该研究包括一个横断面数据集和一个纵向数据集。横断面数据集包括 60 名认知健康对照者、61 名轻度认知障碍（MCI）患者和 63 名痴呆症患者。纵向数据集包括 26 名从认知正常进展为痴呆的参与者和 26 名认知正常的对照者。对横断面组进行了 GWR 比较，调整了淀粉样 PET。还评估了 GWR 与认知表现之间的相关性。纵向数据集用于研究 AD 发病过程中的 GWR 变化。β-淀粉样蛋白沉积型痴呆组表现出最大的 GWR 增加面积，其次是β-淀粉样蛋白沉积型 MCI、无β-淀粉样蛋白沉积型 MCI 和对照组。GWR 增加区域的空间模式不受β-淀粉样蛋白沉积的影响。仅在具有β-淀粉样蛋白沉积的个体中检测到区域 GWR 变化与认知能力下降之间的相关性。GWR 与左顶下叶、外侧枕叶和右中额皮质的 tau PET 呈正相关。纵向研究显示，MCI 中 GWR 在梭状回、下/上颞叶和内嗅皮质周围增加，并在进展为 AD 后扩展到更大的皮质区域。GWR 增加区域的空间模式与β-淀粉样蛋白沉积无关，但与 tau 病重叠。GWR 可以作为 AD 中神经退行性变的有前途的生物标志物。
