彩色多普勒超声评价颈总动脉狭窄方式对血液动力学的影响

Effect of Different Types of Carotic Artery Stenosis on Hemodynamics With Color Doppler Flow Imaging

目的:了解颈总动脉不同形式的狭窄对其血液动力学和病变远端的颈内动脉阻力指数(RI)的影响,为判定脑组织的血流状态提供客观依据。方法:选择颈总动脉同心圆型狭窄Ⅰ组56条和偏心型狭窄Ⅱ组60条,彩色多普勒超声测定颈总动脉狭窄处收缩期最大流速(PSV)、舒张末期血流速度(EDV)和远端的颈内动脉的阻力指数(RI)。结果:颈总动脉狭窄程度80％～90％范围时,Ⅱ组的PSV较Ⅰ组增高;颈总动脉狭窄程度>80％时,Ⅱ组的EDV较Ⅰ组明显减低,Ⅱ组颈内动脉颅外段的RI值比Ⅰ组增大。结论:颈总动脉偏心型狭窄对其血液动力学的影响大,对保证脑组织正常血流量有不利的影响。

Objective: Our aims were to investigate the effect of different types of carotic stenosis on hemodynamics and the (resistant index, RI) of internal carotic artery, and to find a definite and objective method to determine the cerebral blood condition. Methods: Fifty-six pieces of concentric stenosis in group Ⅰ and 60 of eccentric stenosis in group Ⅱ were examined using (color Doppler flow imaging, CDFI) to evaluate (peak systolic velocity, PSV) and the (ending dias-tolic velocity, EDV) at the stenosis segment, and the RI of carotic internal artery. Results: When the stenosis was from 80% to 90% , the PSV in group Ⅱ is much higher than that in group Ⅰ . When the stenosis was higher than 80% , the EDV in group Ⅱ was lower than that in group Ⅰ , and the RI of carotic internal artery in group Ⅱ was higher than that in group Ⅰ . Conclusion: Eccentric stenosis has bad effects on hemodymanics and the maintenance of enough cerebral blood supply.