目的　探讨颈内动脉系统短暂性脑缺血发作 (TIA)病人的血液流变学和脑血流速度的改变及其临床意义。方法　 6 0例颈内动脉系统 TIA病人均在末次发作后 2 4h内进行血液流变学和脑血流速度测定。结果　 1病人组的全血粘度、血浆粘度、红细胞压积及红细胞聚集性各指标均明显增高 ,与正常对照组比较有显著性差异 ;2绝大多数患者脑动脉有严重狭窄或痉挛存在 ,从而引起脑血流速度的改变。结论　血液粘度增高、颅内动脉的狭窄或痉挛引起的血流动力学障碍是导致颈内动脉系统短暂性脑缺血发作的两种机理 Objective To investigate the changes of hemorrheology and cerebral blood flow velocity in patients with internal carotid artery transient ischemic attack (TIA) and its clinical significance. Methods Sixty patients with TIA in the internal carotid artery system underwent hemorheology and cerebral blood flow velocity measurement within 24 hours after the last attack. Results 1 The whole blood viscosity, plasma viscosity, hematocrit and erythrocyte aggregation of all patients were significantly increased, compared with the normal control group were significant differences; 2 most patients with severe cerebral artery stenosis or spasm, thus Cause changes in cerebral blood flow velocity. Conclusions Hemodynamic disorders caused by increased blood viscosity, stenosis or spasm of intracranial arteries are the two mechanisms leading to transient ischemic attacks in the internal carotid artery