在美国,卒中是第三个致死的原因,估计其并发症可造成保健组织每年花费达8亿美元。颅外动脉梗塞联合研究组证实,75%脑血管缺血的病人患有可手术治疗的病变。这类病人多数在出现一过性缺血发作时是迫近脑缺血的第一个征象,但是作为无症状性颈动脉疾病第一个症状的脑血管意外(CVA),其发生的百分率尚不清楚。在理论上,如果在脑血管意外(CVA)发生前就能对这类病人确定诊断,则施行预防性颈动脉动脉内膜切除术可能减少卒中的发生率。一致认为,颈动脉动脉内膜切除术是对患症状性颅外狭窄病人的首选治疗。患一过性缺血性发作(TIA)的病人中30%有继发卒中的危险性;在曾患过卒中 Stroke is the third leading cause of death in the United States and its complication is estimated to have cost health organizations $ 800 million annually. Extracranial Arterial Infarction Joint Study Group confirmed that 75% of patients with cerebrovascular ischemia have operable lesions. Most of these patients are the first sign of impending cerebral ischemia in the event of a transient ischemic attack but the percentage of occurrence of cerebrovascular accidents (CVA), the first symptom of asymptomatic carotid artery disease, is not yet significant clear. In theory, prophylactic carotid endarterectomy may reduce the incidence of stroke if a diagnosis of such patients can be made prior to the onset of cerebrovascular accident (CVA). It was agreed that carotid artery endarterectomy is the preferred treatment for patients with symptomatic extracranial stenosis. Thirty percent of patients with a transient ischemic attack (TIA) have a secondary risk of stroke; those who have had a stroke