High-resolution fiber tract reconstruction in the human brain by means of three-dimensional polarized light imaging.
High-resolution fiber tract reconstruction in the human brain by means of three-dimensional polarized light imaging.
复制标题
通过三维偏振光成像，人脑中的高分辨率纤维道重建。
DOI：
10.3389/fninf.2011.00034
复制
发表时间：
2011
影响因子：
3.5
通讯作者：
Amunts K
中科院分区：
文献类型：
--
作者：
Axer M;Grässel D;Kleiner M;Dammers J;Dickscheid T;Reckfort J;Hütz T;Eiben B;Pietrzyk U;Zilles K;Amunts K
不同大脑区域之间的功能相互作用需要连接纤维束，这是人类连接体的结构基础。为了全面理解从微观到宏观的神经网络元素的结构，必须设想一种多模式和多尺度的方法。然而，来自互补神经成像技术的结果的整合构成了一个特别的挑战。在本文中，我们描述了一种稳定发展的神经成像技术，称为三维偏振光成像(3D-PLI)。它基于轴突周围髓鞘的双折射，能够对构成纤维束的有髓轴突进行高分辨率分析。3D-PLI以亚毫米分辨率，即在中尺度上提供了死后人脑中的空间纤维结构的映射。3D-PLI获得的基本数据结构是纤维和纤维束方向的全面3D矢量场描述--这是后续纤维束成像的基础。为了展示3D-PLI如何有助于解开和组装人类连接体，研究人员采用了一种具有相同技术的多尺度方法。使用了两个互补的最先进的偏振仪，提供了不同的采样网格(像素大小分别为100和1.6 μm)。为了示范性地突出这种方法的潜力，在大脑的选定区域(例如，胼胝体、内囊、桥脑)重建了纤维方位图和3D纤维模型。结果表明，3D-PLI是一种理想的工具，可以作为人类连接体微观和宏观组织水平之间的接口。
Functional interactions between different brain regions require connecting fiber tracts, the structural basis of the human connectome. To assemble a comprehensive structural understanding of neural network elements from the microscopic to the macroscopic dimensions, a multimodal and multiscale approach has to be envisaged. However, the integration of results from complementary neuroimaging techniques poses a particular challenge. In this paper, we describe a steadily evolving neuroimaging technique referred to as three-dimensional polarized light imaging (3D-PLI). It is based on the birefringence of the myelin sheaths surrounding axons, and enables the high-resolution analysis of myelinated axons constituting the fiber tracts. 3D-PLI provides the mapping of spatial fiber architecture in the postmortem human brain at a sub-millimeter resolution, i.e., at the mesoscale. The fundamental data structure gained by 3D-PLI is a comprehensive 3D vector field description of fibers and fiber tract orientations – the basis for subsequent tractography. To demonstrate how 3D-PLI can contribute to unravel and assemble the human connectome, a multiscale approach with the same technology was pursued. Two complementary state-of-the-art polarimeters providing different sampling grids (pixel sizes of 100 and 1.6 μm) were used. To exemplarily highlight the potential of this approach, fiber orientation maps and 3D fiber models were reconstructed in selected regions of the brain (e.g., Corpus callosum, Internal capsule, Pons). The results demonstrate that 3D-PLI is an ideal tool to serve as an interface between the microscopic and macroscopic levels of organization of the human connectome.