Numerical study on the influence of a symmetrical stenosis at the carotid sinus on the flow in the carotid bifurcation
窦部对称狭窄对颈动脉内流场影响的数值研究

The operation of ring constraining, which produce a symmetrical stenosis to artery, was a usually used method to establish an animal model or in vitro arterial atherosclerosis model because the straitness degree can be controlled easily and quantitatively. However, it is unknown how the flow field will be changed, and whether the flow field is similar to that under physiological stenosis when a ring constraining employed to bifurcation or bended artery. To understand tile flow in bifurcation artery under a ring constraining, carotid bifurcation with a symmetrical stenosis to the carotid sinus was instanced. The velocity profile, the secondary flow and the distribution of wall shear stress in the stenosed carotid bifurcation were numerically studied. The results were compared with those in the healthy carotid bifurcation. It was shown that the flow field in the carotid sinus, especially, the distribution of wall shear stress, was changed. Low wall shear stress was axissymmetrically distributed on the wall of the backward site of stenosis. Based on the influence of low wall shear stress on atherosis, it was prompted that atherosis might take place axis-symmetrically in the backward site of stenosis. It is obviously different to the physiological process of atherosis. Therefore, it is indicated that the symmetrical stenosis is not suitable for simulating the carotid sinus stenosis. To simulate the physiological stenosis in the carotid sinus, an asymmetrical stenosis should be employed.