We investigated the effects of atherosclerosis in the carotid region on cerebral haemodynamics. A total of 15 stenosis cases following NASCET criteria were modelled using patient-specific medical image data and an open-source package, SimVascular. The formulation adopted the stabilised Petrov–Galerkin scheme with Newtonian and incompressible assumptions. The boundary conditions employed pulsatile inflow and three-element lumped Windkessel outlet conditions with a rigid wall assumption. We present transitions in the represented CoW during stenosis progression using three-dimensional aortic-cerebral vasculature for the first time. This was driven by the conserved total cerebral blood flow to 50% carotid stenosis (CS) (P-value, P > 0.05), which deteriorated during subsequent stages of CS (P < 0.01), and the effective collateral capability of the communicating arteries (CoAs) activated from a degree of 75% and above (P < 0.0001). The prevalence of ‘complete’ CoW peaked at 50% CS and then declined. Despite the collateral flow, the ipsilateral hemispheric perfusion was moderately reduced (P < 0.01), and the contralateral perfusion was conserved (P > 0.05), revealing the ineffectiveness of collateral capability of CoW at the extreme stages of CS. We identified bulk cerebral auto-regulation effects of the conventional Windkessel model, demonstrating accurate flow reduction in the stenosed artery.

我们调查了颈动脉区域动脉粥样硬化对脑血流动力学的影响。使用患者特定的医学图像数据和开源软件包SimVascular对符合NASCET标准的15例狭窄病例进行建模。该公式采用具有牛顿和不可压缩假设的稳定Petrov-Galerkin方案。边界条件采用脉动性流入，而三元集总的Windkessel出口条件采用刚性壁假设。我们首次使用三维主动脉-脑血管系统，在狭窄进展过程中代表CoW的过渡。这是由于保守的总脑血流达到了50％的颈动脉狭窄（CS）（P值，P> 0.05），其在CS的后续阶段恶化（P <0.01），并且连通动脉（CoA）的有效侧支能力从75％及以上的程度开始激活（P <0.0001）。“完全” CoW的患病率在CS达到50％时达到峰值，然后下降。尽管有侧支血流，同侧半球的灌注却被适度减少（P <0.01），而对侧血流却得以保留（P > 0.05），这表明在CS的极端阶段CoW的侧支能力无效。我们确定了常规Windkessel模型的大量大脑自动调节作用，证明了狭窄的动脉中血流的精确减少。