TCD评价单侧大脑中动脉狭窄或闭塞后的脑血流动力学改变

目的探讨脑血流速度变化与大脑中动脉病变后侧支循环之间的关系。方法选择经血管造影(DSA)确诊的单侧大脑中动脉(MCA)狭窄或闭塞病人,计算经颅多普勒超声(TCD)测得的病侧大脑前动脉(dACA)与健侧大脑中动脉(nMCA)的峰值流速(Vp)比值及双侧大脑后动脉流速比值,与正常对照组比较,观察上述指标与侧支循环建立的关系。结果病例组的dVACA/nVMCA(1.117±0.298)显著高于正常对照组(0.801±0.147),P=0.027;病例组dVPCA/nVPCA(1.097±0.322)与正常组(1.022±0.217)比较差异无统计学意义,经DSA证实有大脑后动脉代偿供血的17例病人(1.353±0.442)与正常组比较差异有统计学意义(P=0.024)。Logistic回归分析显示:狭窄率和dVACA/nVMCA是预测MCA病变后ACA参与代偿的2个独立的相关因素。结论TCD提供的血流动力学参数可以部分反映MCA病变后的侧支循环情况。

Assessment of Hemodynamics Changes after Middle Cerebral Artery Stenosis or Occlusion Using Transcranial Doppler Ultrasound

Objective To investigate the relationship between anterior/posterior cerebral artery flow velocity and the collateral flow patterns in patients with middle cerebral artery stenosis or occlusion. Methods 49 patients with unilateral MCA stenosis/occlusion identified by DSA were selected. Calculating the ratio of ACA flow velocity in affected side with MCA flow velocity in unaffected side and ratio of bilateral PCA flow velocity, compared the data collected from the healthy controls. Results According to the data, we found the patients'dV_ACA/nV_MCA(1.117±0.298)is significantly higher than the controls(0.801±0.147), P=0.027. Logistic regression analysis showed that the stenosal extent and value of dV_ACA/nV_MCA are two independent predicting factors of whether ACA collatery recruited. Conclusion TCD findings can partly reflect the collateral patterns in patients with MCA stenosis or occlusion.