Wuhan Center for Magnetic Resonance, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China; Graduate University of Chinese Academy of Sciences, Beijing, China.
J Neurosci Methods. 2013 Oct 30;220(1):9-17. doi: 10.1016/j.jneumeth.2013.08.023. Epub 2013 Sep 4.
Tree shrews are close relatives of primates, and are increasingly used as models in the research of vision, social stress and neurological/psychiatric diseases. However, neuroimaging techniques, for example magnetic resonance (MR) imaging, are only rarely applied to this species to study the structure and function of the brain. A template MR image set, which is essential for morphometry/volumetric analysis, of tree shrew brain has been lacking in the literature.
High-resolution anatomical MR images and diffusion tensor images of the brain were acquired from male Chinese tree shrews (Tupaia belangeri chinensis), and resampled to an isotropic resolution of 200 μm × 200 μm × 200 μm. Population-based image templates of tree shrew brain, including gray matter/white matter/cerebrospinal fluid probability maps and a fractional anisotropy template, were constructed at this spatial resolution, all in a reference space. Digital masks of representative anatomical structures, including hippocampus, amygdala and cingulum bundle, were created.
With the templates constructed, the volumes of bilateral hippocampus and amygdala were measured using a template-facilitated semi-automated approach to be 59.8 ± 8.3 and 64.3 ± 3.4 mm(3), respectively.
COMPARISON WITH EXISTING METHOD(S): For the first time, high-resolution MR image templates of tree shrew brain were reported. The average volume of bilateral hippocampus measured with the template-facilitated semi-automated approach was found to be similar to the result obtained by the much more labor-intensive manual approach.
The MR image templates obtained in this study are useful for analyzing neuroimage data of tree shrew brain. The templates are freely available to the scientific community upon request.
树鼩与灵长类动物关系密切，越来越多地被用作视觉、社会应激和神经/精神疾病研究的模型。然而，磁共振（MR）成像等神经影像学技术很少应用于该物种，以研究大脑的结构和功能。在文献中，树鼩大脑的形态计量/体积分析所必需的磁共振图像模板一直缺乏。
从雄性中国树鼩（Tupaia belangeri chinensis）获取大脑的高分辨率解剖 MR 图像和弥散张量图像，并重新采样到 200μm×200μm×200μm 的各向同性分辨率。在这个空间分辨率下，构建了树鼩大脑的基于群体的图像模板，包括灰质/白质/脑脊液概率图和各向异性模板，均在参考空间中。创建了代表性解剖结构的数字掩模，包括海马体、杏仁核和扣带束。
使用模板辅助的半自动方法测量双侧海马体和杏仁核的体积分别为 59.8±8.3mm³和 64.3±3.4mm³。
首次报道了树鼩大脑的高分辨率磁共振图像模板。使用模板辅助半自动方法测量的双侧海马体平均体积与手动方法获得的结果相似，手动方法更为繁琐。
本研究获得的磁共振图像模板可用于分析树鼩大脑的神经影像学数据。有需要的话，可以向科学界免费提供这些模板。
