Department of Mechanical Engineering, Sogang University, Seoul, South Korea.
J Atheroscler Thromb. 2012;19(4):397-401. doi: 10.5551/jat.10694. Epub 2012 Jan 12.
The aim of this study was to find a region of low wall shear stress (WSS) in a basilar artery using 3-dimensional (3D) geometric analysis and blood flow simulation.
A 61-year-old patient who underwent follow-up time-of-flight magnetic resonance angiography (TOF-MRA) of the brain was recruited as the subject of the present study. In the basilar artery, the angle of the directional vector was calculated for the region of low WSS. The subject's 3D arterial geometry and blood flow velocity from a transcranial Doppler examination were used for a blood flow simulation study. The regions of low WSS identified by both geometric analysis and blood flow simulation were compared, and these methods were repeated for the basilar arteries of various geometries from other patients.
Two distinct arterial angulations along the basilar artery were identified: lateral and anterior angulations on the anteroposterior and lateral TOF-MR views, respectively. A low WSS region was observed in the distal portion along the inner curvatures of both angulations in the basilar artery. The directional vectors of the region of low WSS calculated by geometric analysis and blood flow simulation were very similar (correlation coefficient= 0.996, p < 0.001). Follow-up MRA confirmed the progression of plaque in the region of low WSS.
Detailed geometric analysis and blood flow simulation of the basilar artery identified lateral and anterior angulations which determined the low WSS region in the distal portion along the inner curvatures of the angulations.
本研究旨在通过三维（3D）几何分析和血流模拟寻找基底动脉低壁切应力（WSS）区域。
本研究招募了一位 61 岁的患者作为研究对象，该患者进行了脑时间飞跃磁共振血管造影（TOF-MRA）随访。在基底动脉中，计算了低 WSS 区域的方向矢量角度。使用经颅多普勒检查获得患者的 3D 动脉几何形状和血流速度，进行血流模拟研究。比较了几何分析和血流模拟确定的低 WSS 区域，并对来自其他患者的各种几何形状的基底动脉重复了这些方法。
在基底动脉中发现了两个明显的动脉角度：前后位 TOF-MR 视图上的外侧和前侧角度。在基底动脉的两个角度的内曲线上，观察到远段存在低 WSS 区域。几何分析和血流模拟计算的低 WSS 区域的方向矢量非常相似（相关系数=0.996，p<0.001）。随访 MRA 证实了低 WSS 区域斑块的进展。
对基底动脉的详细几何分析和血流模拟确定了外侧和前侧角度，这些角度决定了角度内曲线上远段的低 WSS 区域。
