Both the external and internal jugular veins are very important venous systems of the neck, the external jugular vein belongs to the superficial veins of the head and neck and the internal jugular vein belongs to the very important deep veins of the head and neck, so the external jugular vein eventually injects into the deep veins such as the subclavian vein or the angle of the vein, which mainly collects venous blood from the superficial surface of the scalp and face and cannot prevent the backflow of blood although there is a pair of valves. Under normal conditions, the external jugular vein is often not revealed, and pathological jugular vein anger can occur if the patient has heart disease, liver disease and poor reflux caused by superior vena cava obstruction. The internal jugular vein mainly collects venous blood from the skull, meninges, intracranial, lacrimal apparatus and vestibular apparatus, and often travels down the lateral side of the internal carotid artery and common carotid artery within the carotid sheath, and eventually converges to form the cephalic brachial vein, such as when the internal jugular vein is traumatized , due to the inability of the lumen to be occluded and the attraction of the blood flow by the negative pressure of the thoracic cavity, it can lead to air embolism.