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The external jugular vein is a superficial vein of the neck that drains blood from the parotid gland, most of the scalp, and side of the face, then back to the heart. It also assists with blood flow down from the head when other major veins, like the internal jugular vein, are compressed or blocked. Complications affecting the external jugular vein are relatively rare.
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Anatomy
All veins carry deoxygenated blood from the organs, muscles, and other structures back to the heart. Veins typically have a lower blood pressure than arteries.
While their walls are thinner, veins are usually larger in diameter than arteries and hold about 80% of the body’s total blood whereas arteries typically only circulate 20% of the blood.
Structure
The walls of the external jugular vein consist of three layers:
- The tunica adventitia, or the outermost layer of the vein, is the thickest layer composed of loose connective tissue that links to other tissues in the body
- The tunica media, or the middle layer of the vein, is composed of collagen, elastic fibers, and smooth muscle
- The tunica intima, or the innermost layer of the vein, is the thinnest layer of the vein’s wall and is composed of an internal elastic membrane and connective tissue
Location
The external jugular vein forms from the union of the posterior branch of the retromandibular vein and posterior auricular vein beneath the parotid gland at the area behind the angle of the mandible, or lower jaw bone, and beneath the auricle, or earlobe.
The external jugular vein travels from its origin at the angle of the mandible and crosses at a diagonal line across the sternocleidomastoid muscle of the neck. The external jugular vein ends at the middle of the clavicle, or collar bone, where it joins with the subclavian vein. It is a relatively superficial vein that is close to the skin surface under the platysma muscle of the neck.
Function
While the internal jugular vein is a blood drainage pathway deep in the neck that is the main source of blood flow down from the head, blood drainage from the brain, head, and face can occur along multiple alternate routes, including the external jugular vein, to compensate if there is compression obstructing other channels.
The external jugular vein is a superficial pathway responsible for draining the blood supply from the parotid gland (the largest salivary gland), most of the scalp, and side of the face.
The external jugular vein joins the subclavian vein and internal jugular vein to form the brachiocephalic vein, which empties into the superior vena cava. The superior vena cava drains deoxygenated blood from the head, neck, and arms directly to the right atrium of the heart where it will be pumped to the lungs to become oxygenated again.
Clinical Significance
Complications affecting the external jugular vein are very rare, and very few conditions have been reported in medical studies. Although uncommon, malformations of the external jugular vein can occur and potential complications involving it include:
- Aneurysm, or dilation of a blood vessel at least 1.5 times its normal diameter, occurs from weakening of the blood vessel walls. It occurs more commonly in arteries than in veins, and is a rare condition to occur in the external jugular vein with unknown origin. An external jugular vein aneurysm will produce swelling on the side of the neck that is usually painless and increases with coughing, straining, bending, or holding the breath. An aneurysm increases the risk of vein rupture and hemorrhage. Surgery can be performed to treat an external jugular vein aneurysm with excision and ligation, where the vein is removed and blood flow is blocked, or with exclusion and bypass, where the vein is closed off and blood flow is redirected elsewhere
- Hemangioma, or a benign tumor made up of an excess growth of blood vessels, is extremely rare to occur at the external jugular vein with only 10 reported cases documented in published research. A hemangioma of the external jugular vein can produce a swollen lump on the side of the neck, but because a hemangioma is benign, no treatment is required. Surgical removal of an external jugular vein hemangioma can be performed for cosmetic purposes to improve the appearance of the neck
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January 06, 2021 at 08:20AM
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External Jugular Vein: Anatomy, Function, and Significance - Verywell Health
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