Ascending pharyngeal artery

At a glance

English

Ascending pharyngeal artery

Latin (TA2)

Arteria pharyngea ascendens

System

Artery

Region

Head

Side

Paired, left and right

About the ascending pharyngeal artery

The ascending pharyngeal artery is a long, narrow vessel and the smallest of the branches of the external carotid artery. It arises from the deep (medial or posterior) side of the external carotid close to its origin, just above the division of the common carotid artery, and is the most deeply placed of all the branches. In the embryo it is derived from the near portion of the second aortic arch.

From its origin it rises almost vertically between the internal carotid artery and the side wall of the pharynx, lying on longus capitis and the prevertebral fascia and passing beneath stylopharyngeus. It keeps climbing until it meets the underside of the skull base. Along the way it typically divides into two trunks with different territories. The pharyngeal trunk sends branches into the middle and inferior constrictors and stylopharyngeus and to the mucosa lining them, and often to the soft palate and tonsil. The neuromeningeal trunk sends branches up through the jugular foramen and the hypoglossal canal to supply the dura of the posterior cranial fossa and the cranial nerves passing through these openings. An inferior tympanic branch rises to the middle ear, and muscular twigs go to the prevertebral muscles.

The artery is small, but it forms many links with neighbouring vessels: with branches of the maxillary and facial arteries in the pharynx and palate, with the vertebral and occipital arteries around the upper cervical spine, and with meningeal branches of the internal carotid and middle meningeal arteries inside the skull. These connections can open up as collateral routes when a larger vessel is blocked.

The same links matter to interventional radiologists, who may approach tumours of the skull base and jugular foramen, such as paragangliomas, through this artery, and who must avoid letting embolic material pass into the vertebral or internal carotid systems. Its tympanic branch is part of an unusual variant in which the internal carotid artery runs through the middle ear and can be mistaken for a tumour behind the eardrum.

Course and supply

Arises from

Deep (posteromedial) aspect of the external carotid artery near its origin, just above the carotid bifurcation.

Ends in

Ends in pharyngeal branches to the constrictors and in meningeal branches passing through the jugular foramen and hypoglossal canal; also gives an inferior tympanic branch.

Supplies

Supplies the pharyngeal wall, soft palate and tonsil region, prevertebral muscles, middle ear, lower cranial nerves and the dura of the posterior cranial fossa.