颈动脉严重狭窄或闭塞的脑血流动力学改变

目的分析颈内动脉严重狭窄或闭塞(ICA SO)后颅内血液动力学的改变,以提高经颅多普勒超声(TCD)对ICA SO的检出率和准确性。方法ICA SO患者75例,全部经颈部血管彩超检查证实,其中12例经脑血管造影(DSA)或核磁血管造影(M RA)进一步确诊。双侧病变7例,单侧病变68例,共有病变血管82条(狭窄42条,闭塞30条)。全部行TCD检查。结果(1)狭窄或闭塞侧大脑中动脉(M CA)的收缩期血流速度(SPV)及脉动指数(P I)明显低于对侧;(2)前交通动脉(ACoA)开放的患者健侧大脑前动脉(ACA)的峰值流速明显快于ACoA未开放的患者,P I值低于后者;(3)眼动脉之前的ICA SO,患侧虹吸段血流与对侧相比具有明显的低流速低搏动改变;眼动脉之后的ICA SO,患侧虹吸段与对侧相比具有明显的低流速高阻力改变,发出眼动脉之前和之后的ICA SO二者虹吸段收缩期流速无明显差异,但前者P I值明显低于后者;(4)颈外-颈内动脉(ECA-ICA)侧支开放的患者患侧与健侧滑车上动脉(S trA)血流速度无明显差异,但P I值明显低于健侧;(5)前交通动脉(ACoA)开放占50.67%(38/75),后交通动脉(PCoA)开放占52.00%(39/75),颈外-颈内动脉侧支(ECA-ICA)开放占75.44%(43/57)。结论增强对ICA SO时颅内血液动力学改变的认识能提高对ICA SO的检出率和准确性。

Hemodynamic changes of intracranial circulation in the patients with severe carotid stenosis and occlusion

Objective To analyze hemodynamic changes of internal carotid artery severe stenosis and occlusion.Methods All 75 patients were confirmed by Duplex and 12 patients by digital subtraction angiography(DSA)and magnetic resonance angiography(MRA).Transcranial Doppler ultrasound(TCD)performed for all.Results(1)The velocity and pulsatility index(PI)of ipsilateral middle cerebral artery(MCA)to stenosis or occlusion was significantly lower than that of contralateral MCA.(2)The velocity of contralateral anterior cerebral artery(ACA)to stenosis or occlusion in patients of anterior communicating artery(ACoA)opening was increased and PI was reduced compared with that of no ACoA opening.(3)Low flow velocity and resistance wave form were detected when occlusion or severe stenosis occurred proximal to the origin of ophthalmic artery(OA).Low flow velocity and high resistance wave form were found when occlusion or severe stenosis occurred distal to the origin of OA.The PI of the former was significantly lower than the latter.(4)Supratrochlear artery blood flow velocity ipsilateral to stenosis or occlusion was not different compared with contralateral,and the PI was significantly lower than that of the latter.(5)There were 50.67%(38/75)with the opening of ACoA,52.00%(39/75)with the opening of posterior communicating artery(PCoA),and 75.44% with the opening of ophthalmic artery(OA).Conclusion To enhance the recognition of hemodynamic changes of intracranial circulation in the patients with severe carotid stenosis and occlusion can increase diagnosis accuracy of severe ICA stenosis or occlusion.