Wisse Laura E M, Reijmer Yael D, ter Telgte Annemieke, Kuijf Hugo J, Leemans Alexander, Luijten Peter R, Koek Huiberdina L, Geerlings Mirjam I, Biessels Geert Jan
Department of Neurology, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht, The Netherlands Julius Center for Health Sciences and Primary Care, UMC Utrecht, Utrecht, The Netherlands.
Department of Neurology, Brain Center Rudolf Magnus, UMC Utrecht, Utrecht, The Netherlands J. Philip Kistler Stroke Center, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
J Alzheimers Dis. 2015;45(4):1247-56. doi: 10.3233/JAD-142994.
In patients with Alzheimer's disease (AD), atrophy of the entorhinal cortex (ERC) and hippocampal formation may induce degeneration of connecting white matter tracts.
We examined the association of hippocampal subfield and ERC atrophy at 7 tesla MRI with fornix and parahippocampal cingulum (PHC) microstructure in patients with early AD.
Twenty-five patients with amnestic mild cognitive impairment (aMCI) (n = 15) or early AD (n = 10) and 17 controls underwent 3 tesla diffusion MRI to obtain fractional anisotropy (FA) of the fornix and PHC and 7 tesla MRI to obtain ERC and hippocampal subfield volumes. Linear regression analyses were performed, adjusted for age, gender, and intracranial volume.
Fornix FA was significantly lower and subiculum, cornu ammonis (CA) 1, and dentate gyrus &CA4 volume were significantly smaller in patients with MCI or AD as compared to controls. In patients with MCI or AD, fornix FA was positively associated with subiculum volume (β = 0.53, 95% CI 0.10; 0.96), but not with ERC/other subfield volumes. PHC FA was not associated with ERC/subfield volumes.
These findings indicate that in early AD subiculum atrophy is associated with lower FA of the fornix, which primarily consists of axons originating in the subiculum. This suggests that degeneration of subicular cell bodies and their axons are related processes in early AD.
在阿尔茨海默病（AD）患者中，内嗅皮质（ERC）和海马结构的萎缩可能会导致相连白质束的退化。
我们研究了早期AD患者在7特斯拉磁共振成像（MRI）下海马亚区和ERC萎缩与穹窿及海马旁扣带（PHC）微观结构之间的关联。
25例遗忘型轻度认知障碍（aMCI）患者（n = 15）或早期AD患者（n = 10）以及17名对照者接受了3特斯拉扩散MRI检查以获取穹窿和PHC的分数各向异性（FA），并接受了7特斯拉MRI检查以获取ERC和海马亚区体积。进行线性回归分析，并对年龄、性别和颅内体积进行了校正。
与对照组相比，MCI或AD患者的穹窿FA显著降低，而海马下托、海马体1（CA）、齿状回和CA4体积显著减小。在MCI或AD患者中，穹窿FA与海马下托体积呈正相关（β = 0.53，95%可信区间0.10；0.96），但与ERC/其他亚区体积无关。PHC FA与ERC/亚区体积无关。
这些发现表明，在早期AD中，海马下托萎缩与穹窿较低的FA相关，穹窿主要由起源于海马下托的轴突组成。这表明海马下托细胞体及其轴突的退化是早期AD中的相关过程。
