经颅多普勒超声检测颈总动脉或头臂干病变的颅内外血流动力学变化

目的应用经颅多普勒超声（TCD）评估颈总动脉（CCA）或头臂干（BT）重度狭窄或闭塞后的颅内外血流动力学变化及颅内外侧支循环的情况。方法选择经DSA证实的CCA或BT重度狭窄或闭塞患者24例为患者组（1例患者为左侧CCA闭塞,伴BT重度狭窄）,健康体检者20名为对照组。应用TCD检测两组颅内外动脉血流动力学参数的改变,判断侧支开放情况。结果①CCA或BT闭塞的17例患者中,13例CCA或BT局部未探及血流信号,4例呈异常低速高阻的血流信号;CCA或BT重度狭窄的8例中,6例病变局部呈异常高流速伴涡流血流频谱,2例仅探及狭窄以远CCA低流速、低搏动性血流频谱。24例患者的颈外动脉均为血流方向逆转、低搏动性的颈内动脉化血流频谱改变。21例颈内动脉起始段为低流速、低搏动性血流频谱。②大脑中动脉的流速及搏动指数明显低于健侧及对照组（P〈0.01）。眼动脉呈正向低搏动性血流频谱者19例,未探及血流信号者3例,反向切迹血流频谱者2例。③24例患者中,19例（79.2%）Willis环侧支开放;3例有健侧颈外动脉侧支供血。9例呈前循环盗血的血流频谱改变,其中6例（25.0%,6/24）大脑前动脉呈收缩期早期切迹血流频谱改变。2例患侧颈内动脉虹吸段、眼动脉呈反向切迹血流频谱改变。1例BT闭塞患者颈内动脉起始段呈切迹血流频谱改变。结论应用TCD可对CCA或BT病变的颅内外动脉血流动力学改变进行综合评估。

Extra-intracranial hemodynamic changes of common carotid artery or brachiocephalic trunk lesions detected with transcranial Doppler ultrasonography

Objective To evaluate the extra-and intra-cranial hemodynamic changes and collateral circulation after severe stenosis or occlusion of common carotid artery or brachiocephalic trunk(CCA/BT) with transcranial Doppler ultrasonography(TCD).Methods Twenty-four patients with CCA/BT severe stenosis or occlusion confirmed by digital subtraction angiography(DSA) were selected as a patients group,and 20 healthy individuals were used as a control group.TCD was used to detect the changes of the intra-and extra-cranial artery hemodynamic parameters in both groups.The types of collateral patency were identified.Results ①In the 17 patients with CCA/BT occlusion,13 were not detected blood flow signals at the Location of CCA/BT,and 4 showed abnormal low velocity and high resistance blood flow signals;in the 8 patients with CCA/BT severe stenosis,6 showed abnormal high velocity with turbulent flow spectrum at the local lesions and 2 with CCA low velocity and low-pulsatile blood flow spectrum at the sites distal to the stenosis were probed.The external carotid arteries of 24 patients were the reversed blood flow direction and low-pulsatile internal carotid artery blood flow spectrum changes.The origins of internal carotid artery of 21 patients were low velocity and low-pulsatile blood flow spectrum.②The velocity and pulsatility index of the middle cerebral arteries were significantly lower than those of the contralateral sides and the control group(P<0.01).The ophthalmic arteries showed a low-pulsatile forward flow spectrum in 19 patients,no blood flow signals were detected in 3 patients,and the flow spectrum of reversed notches were detected in 2.③In the 24 patients,the circle of Willis in 19(79%) cases showed collateral patency,and 3 had the contralateral external carotid collateral blood supply.Nine patients showed the blood flow spectrum changes with a steal from the anterior circulation and the anterior cerebral artery in 6 of them(25%) showed systolic early notch flow spectrum changes.The internal carotid artery siphon on the affected sides and ophthalmic arteries showed reverse notch flow spectrum changes in 2 patients.The initial segment of the internal carotid artery in 1 patient with BT occlusion showed the notch flow spectrum changes.Conclusion The application of TCD may comprehensively assess the extra-and intra-cranial artery hemodynamic changes of CCA/BT lesions.