Functional Neuroimaging Laboratory, INSERM U825, CHU Purpan, 31059 Toulouse-cedex 3, France.
Brain Res. 2010 Feb 8;1313:62-78. doi: 10.1016/j.brainres.2009.12.007. Epub 2009 Dec 11.
Branching patterns of microvascular networks influence vascular resistance and allow control of peripheral flow distribution. The aim of this paper was to analyze these branching patterns in human cerebral cortex. Digital three-dimensional images of the microvascular network were obtained from thick sections of India ink-injected human brain by confocal laser microscopy covering a large zone of secondary cortex. A novel segmentation method was used to extract the skeletons of 228 vascular trees (152 arterioles and 76 venules) and measure the diameter at every vertex. The branching patterns (area ratios and angles of bifurcations) of nearly 10,000 bifurcations of cortical vascular trees were analyzed, establishing their statistical properties and structural variations as a function of the vessel nature (arterioles versus venules), the parent vessel topological order or the bifurcation type. We also describe their connectivity and discuss the relevance of the assumed optimal design of vascular branching to account for the complex nature of microvascular architecture. The functional implications of some of these structural variations are considered. The branching patterns established from a large database of a human organ contributes to a better understanding of the bifurcation design and provides an essential reference both for diagnosis and for a future large reconstruction of cerebral microvascular network.
微血管网络的分支模式影响血管阻力，并允许控制外周血流分布。本文的目的是分析人类大脑皮层中的这些分支模式。通过共聚焦激光显微镜从印度墨水注射的人脑厚切片中获得微血管网络的数字三维图像，覆盖次级皮层的大片区域。使用一种新的分割方法来提取 228 个血管树（152 个小动脉和 76 个小静脉）的骨架，并测量每个顶点的直径。分析了近 10000 个皮质血管树分叉处的分支模式（面积比和分叉角度），确定了它们的统计特性和结构变化，作为血管性质（小动脉与小静脉）、母血管拓扑顺序或分叉类型的函数。我们还描述了它们的连通性，并讨论了假设的血管分支最佳设计对解释微血管结构复杂性的相关性。考虑了其中一些结构变化的功能意义。从人体器官的大型数据库中建立的分支模式有助于更好地理解分支设计，并为诊断和未来的大脑微血管网络的大规模重建提供必要的参考。
