Modelling the circle of Willis to assess the effects of anatomical variations and occlusions on cerebral flows
Modelling the circle of Willis to assess the effects of anatomical variations and occlusions on cerebral flows
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DOI：
10.1016/j.jbiomech.2006.07.008
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发表时间：
2007-01-01
影响因子：
2.4
通讯作者：
Sherwin, S. J.
中科院分区：
文献类型：
--
作者：
Alastruey, J.;Parker, K. H.;Sherwin, S. J.
用一维压力方程和流动波在柔顺血管中的传播方程模拟了Willis环(Cow)内的血流。该模型从左心室开始，包括供应奶牛的最大动脉。基于已发表的生理数据，它能够捕捉脉搏波沿主动脉、头臂分叉处和整个大脑动脉传播的主要特征。在正常情况下和在颈动脉或椎动脉(VA)闭塞后，研究了完整奶牛的侧支能力及其最常见的解剖变异。我们的结果表明，该系统不需要通过交通动脉的侧支路径来充分地对正常受试者的大脑进行灌流。在血管缺失或闭塞的情况下，交通动脉变得重要，如果颈内动脉(ICA)闭塞，前交通动脉(ACOA)是比后交通动脉(PCoA)更关键的侧支通路。闭塞颈内动脉远不如闭塞颈内动脉危害性大。就平均脑流出流量减少而言，最糟糕的情况是没有大脑前动脉第一段的奶牛合并对侧颈内动脉闭塞。此外，在没有任何严重颈动脉或VA闭塞的患者中，在交通动脉处测量的血流方向与奶牛动脉缺失或闭塞的一侧相对应。最后，我们研究了交通动脉部分闭塞对脑血流的影响，这再次证实了如果颈内动脉闭塞，前交通动脉是比后交通动脉更重要的侧支通路。(C)2006爱思唯尔有限公司。保留所有权利。
Blood flow in the circle of Willis (Cow) is modelled using the 1-D equations of pressure and flow wave propagation in compliant vessels. The model starts at the left ventricle and includes the largest arteries that supply the CoW. Based on published physiological data, it is able to capture the main features of pulse wave propagation along the aorta, at the brachiocephalic bifurcation and throughout the cerebral arteries. The collateral ability of the complete CoW and its most frequent anatomical variations is studied in normal conditions and after occlusion of a carotid or vertebral artery (VA). Our results suggest that the system does not require collateral pathways through the communicating arteries to adequately perfuse the brain of normal subjects. The communicating arteries become important in cases of missing or occluded vessels, the anterior communicating artery (ACoA) being a more critical collateral pathway than the posterior communicating arteries (PCoAs) if an internal carotid artery (ICA) is occluded. Occlusions of the VAs proved to be far less critical than occlusions of the ICAs. The worst scenario in terms of reduction in the mean cerebral outflows is a Cow without the first segment of an anterior cerebral artery combined with an occlusion of the contralateral ICA. Furthermore, in patients without any severe occlusion of a carotid or VA, the direction of flow measured at the communicating arteries corresponds to the side of the CoW with an absent or occluded artery. Finally, we study the effect of partial occlusions of the communicating arteries on the cerebral flows, which again confirms that the ACoA is a more important collateral pathway than the PCoAs if an ICA is occluded. (C) 2006 Elsevier Ltd. All rights reserved.