Ascending pharyngeal artery

Orgin and course

The ascending pharyngeal artery originates from the medial (deep) side of the external carotid artery as the first or second branch of that vessel. It then takes a superior course between the internal carotid artery and pharynx.

The anterior aspect of the artery is crossed by the styloglossus and stylopharyngeus muscles, while the posterior side is just anterior to the longus capitis muscle. The artery ends by anastomosing with the ascending palatine branch of facial artery and the ascending cervical branch of vertebral artery.

Branches and supply

Along its course, the ascending pharyngeal artery gives off three sets of branches to supply the surrounding structures; pharyngeal, inferior tympanic and meningeal branches.

• The pharyngeal branches reach the soft palate by coursing inferiorly between the superior pharyngeal constrictor and levator veli palatini muscles. They supply the pharyngeal constrictors, stylopharyngeus, soft palate, palatine tonsil, and pharyngotympanic (Eustachian) tube.
• The inferior tympanic artery traverses the temporal canaliculus on the inferior surface of the petrous part of temporal bone. It supplies the medial wall of the tympanic cavity.
• Several meningeal branches pass through the foramen lacerum, jugular foramen and hypoglossal canal to supply the adjacent dura mater, hypoglossal (CN XII), glossopharyngeal (CN IX) and vagus (CN X) nerves.

One of the meningeal branches reaches the cerebellar fossa through the jugular foramen. It is called the posterior meningeal artery and it is considered as the terminal branch of the ascending pharyngeal artery.

Anatomical variations

There are several noteworthy anatomical variations related to the origin of the ascending pharyngeal artery. Besides from the external carotid, this artery can originate from the occipital, common carotid, internal carotid or facial arteries.