Li Shuyu, Pu Fang, Shi Feng, Xie Sheng, Wang Yinhua, Jiang Tianzi
Department of Bioengineering, Beijing University of Aeronautics and Astronautics, Beijing, China.
Acta Radiol. 2008 Feb;49(1):84-90. doi: 10.1080/02841850701627181.
Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal.
To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects.
White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane.
Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group.
Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD.
大多数试图阐明阿尔茨海默病（AD）患者与功能连接障碍相关的结构异常的研究都集中在探索皮质灰质的病理变化。然而，连接这些脑区的白质纤维也可能异常。
研究AD患者与健康受试者相比白质体积的区域变化。
使用优化的基于体素的形态学测量（VBM）方法观察从19例AD患者和20名健康受试者（对照组）获取的全脑磁共振图像中的白质体积变化。此外，通过在矢状中切面上手动勾勒胼胝体（CC）的边界，对AD患者和对照组的胼胝体进行进一步研究。然后通过将每个受试者矢状中平面的颅内面积相除，对CC的每个区域进行校正。
与对照组相比，AD患者在CC后部以及左右半球颞叶的白质体积显著减少。此外，CC后部显示出最大统计差异的体素位于左侧。相对于对照组，AD患者中CC的五个亚区也明显更小。
我们的研究结果表明，这些白质区域的异常可能导致AD患者的功能连接障碍。
