Bilston Lynne E, Fletcher David F, Brodbelt Andrew R, Stoodley Marcus A
Prince of Whales Medical Research Institute, University of New South Whales, Barker St, Randwick, NSW 2031, Australia.
Comput Methods Biomech Biomed Engin. 2003 Aug;6(4):235-41. doi: 10.1080/10255840310001606116.
This study was conducted to determine whether local arterial pulsations are sufficient to cause cerebrospinal fluid (CSF) flow along perivascular spaces (PVS) within the spinal cord. A theoretical model of the perivascular space surrounding a "typical" small artery was analysed using computational fluid dynamics. Systolic pulsations were modelled as travelling waves on the arterial wall. The effects of wave geometry and variable pressure conditions on fluid flow were investigated. Arterial pulsations induce fluid movement in the PVS in the direction of arterial wave travel. Perivascular flow continues even in the presence of adverse pressure gradients of a few kilopascals. Flow rates are greater with increasing pulse wave velocities and arterial deformation, as both an absolute amplitude and as a proportion of the PVS. The model suggests that arterial pulsations are sufficient to cause fluid flow in the perivascular space even against modest adverse pressure gradients. Local increases in flow in this perivascular pumping mechanism or reduction in outflow may be important in the etiology of syringomyelia.
本研究旨在确定局部动脉搏动是否足以引起脑脊液（CSF）沿脊髓内的血管周围间隙（PVS）流动。使用计算流体动力学分析了围绕“典型”小动脉的血管周围间隙的理论模型。收缩期搏动被模拟为动脉壁上的行波。研究了波的几何形状和可变压力条件对流体流动的影响。动脉搏动在血管周围间隙中引起流体沿动脉波传播方向移动。即使存在几千帕斯卡的不利压力梯度，血管周围的流动仍会持续。随着脉搏波速度和动脉变形的增加，流速会增加，这既是绝对幅度，也是血管周围间隙的比例。该模型表明，即使存在适度的不利压力梯度，动脉搏动也足以引起血管周围间隙中的流体流动。这种血管周围泵血机制中局部流量的增加或流出的减少可能在脊髓空洞症的病因学中很重要。
