Structural properties of the human corpus callosum: Multimodal assessment and sex differences
Structural properties of the human corpus callosum: Multimodal assessment and sex differences
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DOI：
10.1016/j.neuroimage.2017.02.056
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发表时间：
2017-05-15
期刊：
影响因子：
5.7
通讯作者：
Paus, T.
中科院分区：
文献类型：
--
作者：
Bjornholm, L.;Nikkinen, J.;Paus, T.
白色物质的许多结构特性可以使用多模态磁共振成像（MRI）在体内评估。我们测量了R1和R2弛豫率，髓鞘水分数（MWF）和扩散张量的措施（分数各向异性[FA]，平均扩散率[MD]）在两个样本的年轻人的胼胝体的中矢状面。在第1部分中，我们比较了组织学来源的轴突直径（Aluminitiz等人，1992年），以MRI测量402名年轻男子（19.55 +/- 0.84岁）从雅芳纵向研究的父母和孩子。在第2部分中，我们研究了从1986年北方芬兰出生队列中招募的433名年轻（26.50 +/- 0.51岁）男性和女性的胼胝体FA、MD和磁化传递率（MTR）的性别差异。我们发现，R1，R2，和MWF遵循小轴突密度的前后轮廓。平均MTR的性别差异在胼胝体中相似（男性>女性），而FA中的性别差异在胼胝体段中不同（身体：M > F;脾脏：F > M）。我们认为，R1，R2和MWF的值是由高表面积的髓鞘在高密度的“小轴突”的区域。
A number of structural properties of white matter can be assessed in vivo using multimodal magnetic resonance imaging (MRI). We measured profiles of R1 and R2 relaxation rates, myelin water fraction (MWF) and diffusion tensor measures (fractional anisotropy [FA], mean diffusivity [MD]) across the mid-sagittal section of the corpus callosum in two samples of young individuals. In Part 1, we compared histology-derived axon diameter (Aboitiz et al., 1992) to MRI measures obtained in 402 young men (19.55 +/- 0.84 years) recruited from the Avon Longitudinal Study on Parents and Children. In Part 2, we examined sex differences in FA, MD and magnetization transfer ratio (MTR) across the corpus callosum in 433 young (26.50 +/- 0.51 years) men and women recruited from the Northern Finland Birth Cohort 1986. We found that R1, R2, and MWF follow the anterior-to-posterior profile of small-axon density. Sex differences in mean MTR were similar across the corpus callosum (males > females) while these in FA differed by the callosal segment (Body: M > F; Splenium: F > M). We suggest that the values of R1, R2 and MWF are driven by high surface area of myelin in regions with high density of "small axons".