On May 29, a 56-year-old male patient was admitted to Shanghai Jiuxin Hospital (North Hospital)/III for “sudden onset of left-sided limb weakness for one day” and was admitted to the neurology ward in the emergency department for “cerebral infarction”. The patient’s right internal carotid artery was found to be severely stenosed (70% stenosis) after the relevant examination, and the joint interventional treatment team led by Liu Jianren and Wu Danhong, chief of the neurology department of the North and South Hospitals, successfully completed the endovascular interventional stent implantation after the family’s consent. Dr. Liu Jianren, the chief physician, made a small puncture in the artery at the root of the patient’s thigh and placed the balloon and stent into the lesion through the natural vascular channel without any pain, performed balloon dilation, improved the narrowed lesion, and implanted the carotid stent that “never rusts” and “does not affect MRI. “Carotid artery stents are implanted. Before balloon dilation and stenting, a protective umbrella (which allows blood flow but catches dislodged emboli) is placed distal to the lesion to prevent intraoperative dislodgement of the emboli and cerebral infarction, and the umbrella is removed postoperatively. The operation went smoothly and the carotid stenosis improved significantly, and the patient was discharged with good recovery of limb function and no recurrence of cerebral infarction at the time of follow-up. According to Director Jianren Liu, in the past, intensive antithrombotic and lipid-lowering drugs were first used for carotid stenosis, and surgery was also preferred to internal carotid artery endothelial dissection, but in recent years, with the continuous maturation and development of endovascular stenting technology and intraoperative brain protection technology, carotid artery stenting has increasingly shown its own advantages. It is particularly suitable for patients with high lesions, carotid stenosis due to radiotherapy, elderly people who are intolerant of open surgery and anesthesia, and diabetic patients who are prone to trauma infection. Accumulating data from clinical studies further suggest that carotid artery stenting is a safe and effective method. According to the latest data from the World Health Organization (WHO), 55 million people worldwide will have a disabling or non-disabling stroke in their lifetime, with 15 million new strokes occurring each year. Strokes are classified as ischemic or hemorrhagic, with ischemic strokes (i.e., cerebral infarction) accounting for about 70%. Carotid atherosclerosis is a common risk factor for ischemic stroke. Severe carotid stenosis or occlusion can lead to ischemic stroke, and patients often present with severe neurological deficits such as impaired consciousness, hemiplegia, aphasia, dementia, and even life-threatening conditions. Several large clinical trials have demonstrated that carotid artery stenting (CAS) can effectively improve the revascularization of patients with symptomatic carotid stenosis and significantly reduce the risk of future strokes. In the worldwide guidelines as well as the latest Chinese guidelines “Guidelines for secondary prevention of ischemic stroke and transient ischemic attack (TIA) 2014”, it is clearly stated that: 1. Carotid artery stenting is recommended for patients with recent TIA or ischemic stroke combined with severe stenosis (70-90%) of the ipsilateral extracranial carotid segment within 6 months (Class I, Level A evidence); 2. Carotid stenting is recommended for patients with a recent TIA or ischemic stroke within 6 months combined with moderate stenosis (50-69%) of the ipsilateral extracranial carotid segment (Class I, Level A evidence).