Carotid stenosis is a relatively serious cerebrovascular disease because it has a high chance of causing a cerebral infarction. According to statistics, 60% of clinical cerebral infarctions are inextricably linked to carotid artery stenosis, which shows the threat of this disease to human health and safety. In addition, carotid artery stenosis can also result in poor blood supply to the brain, mental retardation, visual field loss and other adverse consequences. There are two medical treatment options for carotid artery stenosis, one is medication and the other is surgery. Drug treatment is mainly for mild patients with low degree of stenosis, but if the patient has high degree of stenosis and the condition is relatively serious, the treatment effect is not good with drugs alone. For the treatment of moderate to severe carotid artery stenosis, surgery can be used according to the patient’s own situation, so that the possibility of recovery is greater. Many experts at home and abroad advocate the use of carotid endarterectomy to treat carotid stenosis, and with the widespread development of this technique, many patients have seen the dawn of health, and the medical community has called it the “gold standard” for the treatment of carotid stenosis. Every neurosurgical procedure requires close preoperative evaluation, including carotid endarterectomy, and many patients and their families delay treatment because they are unaware of the indications for this procedure. What is the preoperative evaluation for carotid endarterectomy? In other words, what are the indications for carotid endarterectomy? The indications are as follows: 1. First, the specific degree of stenosis needs to be clarified by cranial CT or whole brain angiography, and surgery can be considered for those with stenosis between 50% and 70%, and those with frequent episodes of transient cerebral ischemia. 2.