年龄对颈动脉血流动力学影响的初步研究

目的研究年龄对颈总动脉血流动力学参数的影响。方法 47名不同年龄健康受试者的双侧颈动脉分别被MR扫描,在颈动脉分叉部位下2 cm颈总动脉平面上,把颈总动脉壁平均分为24等份,利用相位对比MRI和三维抛物面模型拟合的方法,计算每个空间位置一个心动周期内的平均剪切力以及空间位置上最小的剪切力。观察年龄对颈动脉血流动力学参数的影响。结果有9名受试者的9条颈动脉,因难以耐受较长时间的扫描或扫描结果有伪影,在分析时排除。余85条血管颈动脉血管壁上平均剪切力及空间位置上最低剪切力分别为(7.45±2.12)dyne/cm2和(5.98±1.93)dyne/cm2,均与年龄负相关(P<0.05)。结论随着年龄的增长,颈总动脉总的平均剪切力和空间分布最低剪切力下降。

Effect of Age on Carotid Hemodynamics

Objective To study the effect of age on the hemodynamics of common carotid artery.Methods 47 healthy volunteers were studied.Wall shear stress(WSS) values localized at common carotid artery 2 cm below the bifurcation were calculated with cine phase-contrast MR imaging combined three-dimensional paraboloid(3DP) model.On the spatial distribution,common carotid artery wall was divided into 24 equal parts.Calculate the mean WSS in a cardiac cycle on each part,and choose the minimal WSS value.Then the effects of age on the average WSS and minimal WSS were observed.Results Total 94 common carotid arteries of 47 health volunteers were examined,in which 9 carotid arteries in 9 volunteers were excluded because of uninterpretable high-resolution MRI findings or volunteer’s intolerance for the detection.In the remaining 85 common carotid arteries,the average WSS and the minimal WSS during a cardiac cycle on the spatial distribution were(7.45±2.12) dyne/cm2 and(5.98±1.93) dyne/cm2 respectively.Both average WSS and minimal WSS were negative correlated with age(P<0.05).Conclusion With the age increased,mean WSS and minimal WSS on the spatial distribution of common carotid artery decreased.