The carotid arteries are located in the neck of the human body, with one on each side. They are blood vessels that emanate from the aorta in the thoracic cavity and reach the brain, and are responsible for the supply of blood to the brain. The carotid arteries are divided outside the skull into two branches: the external carotid artery, which is responsible for the blood supply to the face and scalp, and the internal carotid artery, which is responsible for the blood supply to the brain. When the carotid arteries are narrowed or occluded, it is called carotid artery disease. The incidence of carotid artery disease increases with age. For example, the incidence of carotid artery stenosis is only 1% in people aged 50-59 years old, while the incidence is as high as 10% in people aged 80-90 years old. Under normal physiological conditions, the lining of the carotid artery is smooth and the lumen is unobstructed, but as we age, a crust-like substance called “plaque” gradually forms on the arterial wall, which is formed by cholesterol, calcium salts and fibrous tissue. As plaque forms, the arteries become stiff and the lumen narrows. This pathological process is called atherosclerosis or hardening of the arteries. The gradual increase in the size of the plaque causes a blockage of blood flow in the carotid arteries, at which point you develop carotid artery disease, a serious health condition that can lead to stroke. As the surface of the plaque is rough and irregular, platelets in the blood tend to gather on it and gradually form thrombi in the carotid artery and its main branches. The formation of blood clots in the carotid arteries slows down or stops the blood flow, preventing the delivery of sufficient oxygen to the brain and leading to stroke. More commonly, small plaques are dislodged from the surface of large plaques into the bloodstream and embolize one of the small arteries supplying the brain, which can also lead to stroke. Atherosclerosis is an inevitable tendency in older people, but fortunately there are steps you can take to slow the progression of carotid artery disease. Quitting smoking is the most important way to avoid the onset of this disease, but others include: regular physical activity; eating a healthy diet; maintaining your ideal body weight; and controlling risk factors for atherosclerosis, including diabetes, high blood pressure, and hyperlipidemia. What are the symptoms at the onset? Carotid artery disease can be asymptomatic in its early stages. Unfortunately, people with carotid artery disease can have a stroke without warning. Some patients may have a few symptoms called transient ischemic attacks (TIAs), or “mini-strokes”. Symptoms can last from a few minutes to a few hours and include: weakness, numbness, or a feeling of tremor in one limb; lack of movement of a limb; blurred vision in one eye (many people describe the sensation as a black shadow in front of their eyes); and slurred speech. Most of these symptoms disappear within 24 hours. However, you should not ignore it, as this transient ischemic attack is a sign that you may have a serious stroke in the near future. Seek immediate medical attention if you experience any of the above symptoms. What tests are needed to determine if I have carotid artery disease? During your visit, your doctor will ask you about your general condition, including your medical history and symptoms, such as whether you are a smoker, whether you have a history of high blood pressure, and when and how often your symptoms occur. In addition, the doctor will perform a physical examination, including a carotid artery auscultation with a stethoscope, which may result in a murmur if there is carotid artery stenosis. After the history and physical examination, if the doctor has a high suspicion that you have carotid artery disease, he will recommend a carotid ultrasound. This is a painless procedure in which the doctor holds an ultrasound probe and examines the carotid arteries to see how fast and how much blood is flowing. This test gives the doctor a general idea of whether your carotid arteries are narrowed or occluded. Carotid ultrasound can detect most carotid artery disease, but if the ultrasound does not provide enough information, the doctor may perform the following tests: CTA: carotid artery enhancement CT + 3D reconstruction. It can clearly show the specific shape of the carotid arteries and intracranial blood vessels, and can visualize the stenosis area.MRA: Carotid artery enhancement nuclear magnetic resonance (NMR). MRI uses radio waves and a magnetic field to form specific images that can show the form of blood flow and help evaluate the carotid arteries. A gadolinium-containing contrast agent is sometimes injected for accuracy. Arteriography: During this test, the doctor injects a contrast material directly into the artery to obtain an image. It is possible to visualize the location and extent of arterial narrowing. However, arteriography is an invasive test that carries certain risks, including the very low probability of stroke. For this reason, doctors generally do not use it as a preferred test, except for direct imaging in preparation for carotid stenting, which will be discussed specifically below. How is carotid artery disease treated? Treatment depends largely on the severity of your condition. Specifically, it depends on the presence or absence of symptoms caused by carotid artery disease and your general health. However, your doctor may first recommend medication and lifestyle changes. If you have other medical conditions, it is important to follow your doctor’s recommendations. For example, if you have diabetes, you should monitor and control your blood sugar regularly; if you have high blood pressure, you should take antihypertensive medication to control your blood pressure according to your doctor’s advice; if you have hyperlipidemia, you should monitor your blood lipids regularly and take lipid-lowering medication according to your physician’s advice. If you are a smoker, you should quit smoking. In addition, you can take a small amount of aspirin daily to reduce blood viscosity. Secondly: Your doctor will combine your condition and give you a comprehensive treatment, including the basic treatment described earlier, plus surgical or endoluminal treatment: e.g. carotid endarterectomy, carotid stenting.