目的：探讨短暂性脑缺血发作（ＴＩＡ）的发病机制。方法：对３０例颈动脉系统ＴＩＡ进行三维经颅多普勒超声（３Ｄ－ＴＣＤ）、脑血管血液动力学参数（ＣＶＤＩ）及血液流变学检查分析。结果：绝大多数患者存在严重脑动脉硬化、脑动脉狭窄、脑内微循环障碍；病灶侧平均脑血流量下降，血管自身调节功能减退；全血粘度、血浆粘度及血小板聚集率明显增高。结论：脑血液动力学障碍是ＴＩＡ发病机制之一。 Objective: To investigate the pathogenesis of transient ischemic attack (TIA). Methods: Thirty patients with carotid artery TIA were examined by 3D-TCD, CVDI and hemorheology. Results: The majority of patients had severe cerebral arteriosclerosis, cerebral artery stenosis and microcirculation disturbance in the brain. Mean cerebral blood flow decreased on the lesion side and the autoregulation of blood vessels decreased. The whole blood viscosity, plasma viscosity and platelet aggregation rate were significantly increased. Conclusion: Cerebral hemodynamic disorder is one of the pathogenesis of TIA.