Gahm Jin Kyu, Shi Yonggang
Laboratory of Neuro Imaging, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, USA.
Med Image Comput Comput Assist Interv. 2017 Sep;10433:21-30. doi: 10.1007/978-3-319-66182-7_3. Epub 2017 Sep 4.
In brain shape analysis, the striatum is typically divided into three parts: the caudate, putamen, and accumbens nuclei for its analysis. Recent connectivity and animal studies, however, indicate striatum-cortical inter-connections do not always follow such subdivisions. For the holistic mapping of striatum surfaces, conventional spherical registration techniques are not suitable due to the large metric distortions in spherical parameterization of striatal surfaces. To overcome this difficulty, we develop a novel striatal surface mapping method using the recently proposed Riemannian metric optimization techniques in the Laplace-Beltrami (LB) embedding space. For the robust resolution of sign ambiguities in the LB spectrum, we also devise novel anatomical contextual features to guide the surface mapping in the embedding space. In our experimental results, we compare with spherical registration tools from FreeSurfer and FSL to demonstrate that our novel method provides a superior solution to the striatal mapping problem. We also apply our method to map the striatal surfaces from 211 subjects of the Human Connectome Project (HCP), and use the surface maps to construct a cortical connectivity atlas. Our atlas results show that the striato-cortical connectivity is not distinctive according to traditional structural subdivision of the striatum, and further confirms the holistic approach for mapping striatal surfaces.
在脑形态分析中，纹状体通常被分为三个部分：尾状核、壳核和伏隔核，以便进行分析。然而，最近的连通性研究和动物研究表明，纹状体与皮质之间的相互连接并不总是遵循这种细分。对于纹状体表面的整体映射，传统的球面配准技术并不适用，因为纹状体表面的球面参数化存在较大的度量失真。为了克服这一困难，我们利用拉普拉斯 - 贝尔特拉米（LB）嵌入空间中最近提出的黎曼度量优化技术，开发了一种新颖的纹状体表面映射方法。为了在LB谱中稳健地解决符号模糊问题，我们还设计了新颖的解剖学上下文特征，以指导嵌入空间中的表面映射。在我们的实验结果中，我们与来自FreeSurfer和FSL的球面配准工具进行了比较，以证明我们的新方法为纹状体映射问题提供了更好的解决方案。我们还应用我们的方法对人类连接组计划（HCP）的211名受试者的纹状体表面进行映射，并使用表面映射构建一个皮质连通性图谱。我们的图谱结果表明，根据纹状体的传统结构细分，纹状体与皮质之间的连通性并无明显差异，并进一步证实了映射纹状体表面的整体方法。
