External jugular vein
The external jugular vein begins near the mandibular angle, just below or within the substance of the parotid gland. It descends obliquely along the neck, superficial to the sternocleidomastoid muscle. Upon reaching the clavicle, it crosses the deep cervical fascia and ends by draining into the subclavian vein. The main function of the external jugular vein is to drain the superficial structures of the head, i.e. the scalp and face.
|Drains from||Confluence of posterior division of the retromandibular vein with the posterior auricular vein|
|Tributaries||Cervical, suprascapular, anterior jugular veins|
|Drains to||Subclavian vein|
|Drainage area||Scalp, face|
This article will discuss the anatomy and function of the external jugular vein.
Anatomy and course
The external jugular vein begins at the level of the mandibular angle, just below the parotid gland. It arises from the confluence of the posterior division of the retromandibular vein and the posterior auricular vein. It then descends obliquely downwards along the neck, deep to the platysma, the superficial cervical fascia and the skin. It courses superficial to the sternocleidomastoid muscle, being separated from it by the deep cervical fascia. Along its course, the external jugular vein crosses the transverse cutaneous nerve, lying parallel with the great auricular nerve. It maintains this relation until it reaches the midpoint of the clavicle, where it crosses the deep cervical fascia and ends in the subclavian vein, lateral or anterior to scalenus anterior muscle.
Besides the posterior division of the retromandibular vein and the posterior auricular vein, the external jugular vein also receives the cervical, suprascapular and anterior jugular veins as tributaries near its termination. Occasionally, it is also joined by the occipital vein and a branch from the internal jugular vein. The function of the external jugular vein is to drain the venous blood from the superficial parts of the scalp and face, as well as several deeper regions of the head.
The external jugular vein has significance in everyday clinical practice. Namely, increased pressure in the superior vena cava or the right atrium of the heart causes blood flow to back up into the internal and external jugular veins. This results in jugular venous distention (JVD), in which the jugular veins, and especially the external jugular vein due to its superficial location, become visibly engorged. Thus, distended neck veins can be a telltale sign of conditions such as congestive heart failure, cardiac tamponade, pulmonary hypertension or superior vena cava obstruction.