The first thing to do for an ultrasound examination of the carotid arteries is to have the patient lie flat or on his or her side on the examination bed, exposing the neck. The examination of the carotid vessels includes the bilateral common carotid artery, internal carotid artery, external carotid artery and vertebral artery. The examination generally starts from the proximal end and proceeds to the distal end to observe whether the walls of the carotid arteries are clear, whether the intima-media of the walls are thickened, and whether sclerotic plaques are formed. If the intima-media is thickened to form a sclerotic plaque, the degree of thickening should be measured to see if it causes luminal narrowing, and color Doppler should be used to detect whether the blood flow velocity in the lumen is normal. When observing the vertebral artery, the internal diameter of the lumen is measured, the velocity of blood flow in the lumen is measured, and the normal course of the vertebral artery is also observed. Color ultrasound examination of the carotid vessels is very intuitive, convenient and easy to perform, and can diagnose common diseases of the carotid arteries, which provides great help to clinicians in their treatment.