Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
J Int Neuropsychol Soc. 2012 May;18(3):414-27. doi: 10.1017/S1355617712000227. Epub 2012 Mar 6.
Few studies have applied multiple imaging modalities to examine cognitive correlates of white matter. We examined the utility of T2-weighted magnetic resonance imaging (MRI) -derived white matter hyperintensities (WMH) and diffusion tensor imaging-derived fractional anisotropy (FA) to predict cognitive functioning among older adults. Quantitative MRI and neuropsychological evaluations were performed in 112 older participants from an ongoing study of the genetics of Alzheimer's disease (AD) in African Americans. Regional WMH volumes and FA were measured in multiple regions of interest. We examined the association of regional WMH and an FA summary score with cognitive test performance. Differences in WMH and FA were compared across diagnostic groups (i.e., normal controls, mild cognitive impairment, and probable AD). Increased WMH volume in frontal lobes was associated with poorer delayed memory performance. FA did not emerge as a significant predictor of cognition. White matter hyperintensity volume in the frontal and parietal lobes was increased in MCI participants and more so in AD patients relative to controls. These results highlight the importance of regionally distributed small vessel cerebrovascular disease in memory performance and AD among African American older adults. White matter microstructural changes, quantified with diffusion tensor imaging, appear to play a lesser role in our sample.
很少有研究应用多种成像方式来研究白质的认知相关性。我们研究了 T2 加权磁共振成像（MRI）衍生的脑白质高信号（WMH）和扩散张量成像衍生的各向异性分数（FA）在预测老年人群认知功能中的作用。在一项正在进行的关于非裔美国人阿尔茨海默病（AD）遗传学的研究中，对 112 名老年参与者进行了定量 MRI 和神经心理学评估。在多个感兴趣的区域测量了局部 WMH 体积和 FA。我们研究了局部 WMH 和 FA 综合评分与认知测试表现的相关性。在不同的诊断组（即正常对照组、轻度认知障碍和可能的 AD）之间比较了 WMH 和 FA 的差异。额叶 WMH 体积增加与延迟记忆表现较差有关。FA 并未成为认知的显著预测因素。与对照组相比，MCI 参与者的额叶和顶叶的 WMH 体积增加，AD 患者的 WMH 体积增加更为明显。这些结果强调了在非裔美国老年人群中，与认知障碍和 AD 相关的局灶性小血管脑血管疾病的重要性。在我们的样本中，使用扩散张量成像量化的白质微观结构变化似乎作用较小。
