Artery: External carotid artery | |
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Arteries of the neck - right side. The external carotid artery arises from the common carotid artery - labeled Common caroti on the figure. | |
Plan of branches of internal maxillary artery. (External carotid labeled at bottom left.) | |
Latin | arteria carotis externa |
Gray's | subject #144 551 |
Source | common carotid artery |
Branches | superior thyroid, lingual, facial, ascending pharyngeal, occipital, posterior auricular, maxillary, superficial temporal |
MeSH | Carotid+Artery,+External |
In human anatomy, the external carotid artery is a major artery of the head and neck. It arises from the common carotid artery when it bifurcates into the external and internal carotid artery.
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The external carotid artery begins at the level of the upper border of thyroid cartilage, and, taking a slightly curved course, passes upward and forward, and then inclines backward to the space behind the neck of the mandible, where it divides into the superficial temporal and maxillary artery within the parotid gland.
It rapidly diminishes in size in its course up the neck, owing to the number and large size of the branches given off from it.
In the child, it is somewhat smaller than the internal carotid; but in the adult, the two vessels are of nearly equal size. At its origin, this artery is more superficial, and placed nearer the middle line than the internal carotid, and is contained within the carotid triangle.
The external carotid artery is covered by the skin, superficial fascia, Platysma, deep fascia, and anterior margin of the Sternocleidomastoideus; it is crossed by the hypoglossal nerve, by the lingual, ranine, common facial, and superior thyroid veins; and by the Digastricus and Stylohyoideus; higher up it passes deeply into the substance of the parotid gland, where it lies deep to the facial nerve and the junction of the temporal and internal maxillary veins.
Medial to it are the hyoid bone, the wall of the pharynx, the superior laryngeal nerve, and a portion of the parotid gland.
Lateral to it, in the lower part of its course, is the internal carotid artery.
Posterior to it, near its origin, is the superior laryngeal nerve; and higher up, it is separated from the internal carotid by the Styloglossus and Stylopharyngeus, the glossopharyngeal nerve, the pharyngeal branch of the vagus, and part of the parotid gland.
From inferior to superior:
Mnemonics are traditionally used to commit these branches to memory.[2] Perhaps referring to the medical school interviewing process, a commonly taught mnemonic for the external carotid branches is "Some Attendings Like Freaking Out Potential Medical Students." A similar but more memorable and vulgar mnemonic omits the minor Occipital . Another is "Some Ancient Lovers Find Old Positions More Stimulating." As well as, "Some Anatomists Like Fornicating, Others Prefer S & M" and "Some angry lady figured out PMS." and an Egyptian one: "Some American Lady Found Our Pyramids So Magnificent."
A memorable mnemonic appears in Samuel Shem’s classic novel The House of God (1978). Here Shem uses the older terms External maxillary artery for Facial artery and Internal maxillary artery for Maxillary artery. The Ascending pharyngeal and Superior thyroid appear in their correct sequence, while the names of the two terminal branches are reversed:
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