van der Zwan A, Hillen B, Tulleken C A, Dujovny M
Department of Neurosurgery, University Hospital Utrecht, The Netherlands.
Stroke. 1993 Dec;24(12):1951-9. doi: 10.1161/01.str.24.12.1951.
We have previously reported that the topographic variability of the territories of the anterior, middle, and posterior cerebral arteries is much larger than is generally considered in the literature. In the current study, we quantitatively investigated the variability of the territorial distribution of the major cerebral arteries and analyzed its relation to the variability of the circle of Willis.
In 23 human brains, the volumes of the major cerebral territories were calculated and the diameters of the contributing arteries were measured and standardized for size.
The variability of the standardized territorial volumes proved to be considerably large and strongly correlated with the variability of the diameters of the arteries emanating from the circle of Willis. Furthermore, the relative vascular densities in the gray and white matter were determined. Taking these densities into account, an estimation of the relative peripheral resistance of the contributing arteries was made.
We hypothesize that the morphological variability of the cerebral vascular system is related to the peripheral resistance of the major cerebral arteries and, consequently, to flow patterns, both of which are hemodynamic factors. We suggest that hemodynamic factors predominantly determine the form and size of the cerebral vascular system.
我们之前曾报道，大脑前动脉、大脑中动脉和大脑后动脉供血区域的地形变异性比文献中普遍认为的要大得多。在本研究中，我们定量研究了主要脑动脉供血区域分布的变异性，并分析了其与 Willis 环变异性的关系。
对 23 个大脑进行研究，计算主要脑区的体积，并测量供血动脉的直径并按大小进行标准化。
标准化脑区体积的变异性被证明相当大，并且与 Willis 环发出的动脉直径的变异性密切相关。此外，还测定了灰质和白质中的相对血管密度。考虑到这些密度，对供血动脉的相对外周阻力进行了估算。
我们推测脑血管系统的形态变异性与主要脑动脉的外周阻力有关，进而与血流模式有关，这两者都是血流动力学因素。我们认为血流动力学因素主要决定了脑血管系统的形态和大小。
