The stenosis of the extracranial carotid artery is the main cause of ischemic stroke and transient ischemic attack (TIA), and with the aging of our population, the incidence of atherosclerosis is also increasing, and stroke has become one of the major fatal diseases. Therefore, standardized diagnosis and treatment of extracranial carotid stenosis is of great importance . The imaging evaluation is an extremely important part of the surgical management. It is necessary not only to accurately and quantitatively determine the presence, degree and extent of carotid stenosis, but also to make a comprehensive evaluation of the intracranial situation, the vascular condition of the patient’s body and the anatomy of the neck, so as to clarify the need for surgical intervention, to grasp the indications for surgery, to guide the clinical formulation of treatment plans and to improve the patient’s prognosis. I. Determination of symptomatic/asymptomatic carotid stenosis The treatment options and prognosis of patients with symptomatic and asymptomatic carotid stenosis are very different and need to be strictly differentiated. MR is non-radioactive, has higher tissue resolution than CT, and can clearly show the lesions in the brain, and its diffusion sequence is very sensitive to fresh cerebral infarction. Its diffusion sequence is even more sensitive to fresh brain infarction foci. In patients with TIA or cerebral infarction, it is more important to evaluate the cerebral perfusion in time and to save the ischemic brain tissue in the “semi-dark zone” according to the results. Therefore, CT/MR perfusion imaging is recommended for patients who are eligible for it to indicate the timing of clinical intervention. Imaging can assist in the clinical determination of symptomatic/asymptomatic carotid stenosis and provide a preliminary classification for the next evaluation of luminal stenosis. II. Assessment of the degree of carotid stenosis In high-risk patients, Doppler ultrasound is recommended as the imaging modality of choice to evaluate the degree of stenosis and hemodynamic impact. Ultrasound is noninvasive, real-time, simple, and inexpensive, and has great advantages for the detection and follow-up of extracranial segments of carotid arteries located on the body surface, as well as the ability to measure the degree of carotid stenosis while observing the hemodynamic changes and plaque composition within the carotid artery. CTA/MRA is recommended for patients who cannot be clearly visualized by Doppler ultrasound, who have complex vascular conditions requiring reconstruction, and for patients whose ultrasound findings suggest carotid stenosis and require further confirmation for possible recanalization procedures. With the widespread use of multi-row spiral CT and high-resolution MR, CTA and MRA have largely replaced invasive DSA examinations, and can display carotid artery morphology in multiple planes in three dimensions and at any angle, accurately measure the degree of carotid artery stenosis, and show the extracarotid lumen, especially the canal wall; and can indicate possible vascular variants and anatomical abnormalities of the neck, such as patients with combined carotid tumors after radiotherapy. When extracranial carotid lesions are detected, CTA/MRA can further reveal possible intracranial vascular lesions and provide a more comprehensive assessment of the indications for surgery, the choice of surgical approach, and the difficulties that may be encountered during surgery. DSA is still considered to be the gold standard for evaluating the degree of carotid stenosis. However, DSA is an invasive test, which is risky and expensive, and it can only show the intraluminal condition of the carotid artery, so it is not recommended for all patients. Surgical indications Surgical recanalization of carotid stenosis in the extracranial segment includes carotid endarterectomy (CEA) and carotid angioplasty and stent placement (CAS). Carotid endarterectomy is the gold standard and traditional procedure for the treatment of carotid stenosis, while carotid stenting is an interventional procedure with minimally invasive features that can reduce the perioperative complications and mortality in high-risk patients. IV. ISSUES AND PROSPECTS In recent years, the nature of plaque localized to carotid stenosis has attracted more and more attention as research has progressed. Some of the stenoses caused by vulnerable plaques are not serious and the patients’ usual clinical manifestations can be insignificant, but once the plaque ruptures, it will trigger fatal lesions such as emboli dislodging and embolization of cerebral vessels and severe stenosis of carotid arteries. For the current management guidelines applied in surgery, only the degree of stenosis of the carotid artery is evaluated, and the stability of the plaque is not considered. Especially for patients with asymptomatic carotid stenosis, the choice between surgical recanalization or medical drug therapy alone requires a comprehensive weighing of risks and benefits. Ultrasound-enhanced angiography has been able to show neovascularization within atherosclerotic vulnerable plaques by microbubbles, providing an early indication of plaque instability. The rapid development of high-resolution magnetic resonance has provided more one-stop assessment of carotid stenosis morphology, hemodynamics, plaque nature, intracranial vascularity, and cerebral infarction for a comprehensive assessment. In conclusion, imaging can evaluate the extent of carotid stenosis in extracranial segments and show intracranial lesions that may be causing symptoms. Proper selection of imaging methods can effectively assess the surgical indications for patients with carotid stenosis, guide clinical development of timely treatment plans, and improve patient prognosis. In the future, with the development of imaging technology, it is expected that the one-stop shop will provide an earlier and more comprehensive assessment of the morphology, degree, extent, and function of carotid artery stenosis, providing more useful guidance for the reasonable measurement of surgical risks and benefits.