Middle meningeal artery

At a glance

English

Middle meningeal artery

Latin (TA2)

Arteria meningea media

System

Artery

Region

Head

Side

Paired, left and right

About the middle meningeal artery

Of the arteries that feed the meninges, this one is the biggest, outranking the anterior and posterior meningeal vessels. It usually arises in the infratemporal fossa from the first, or mandibular, part of the maxillary artery. From there it climbs between the sphenomandibular ligament and lateral pterygoid, threading through the loop formed by the auriculotemporal nerve as its roots join, and the nerve clasps it so closely that the pair are easy to find together in dissection and easy to damage together in surgery. The sphenoid's foramen spinosum then admits it to the middle cranial fossa.

Inside the skull it runs forwards and outwards in a groove on the greater wing of the sphenoid and splits into two main branches. The frontal, or anterior, branch is larger. It crosses the greater wing to the front lower, or sphenoidal, angle of the parietal, where it often runs in a bony tunnel, then fans out between dura and bone, some twigs reaching the vertex and others the occipital region. The parietal, or posterior, branch curves backwards over the squamous temporal bone to the back of the parietal bone. The branches lie in the outer, periosteal layer of dura and supply the bone more than the dura itself, deeply grooving the inside of the calvaria. They anastomose with their fellows across the midline, with the other meningeal arteries and, through the skull, with scalp vessels.

Soon after entering, the artery gives small twigs to the trigeminal ganglion and nearby dura; a petrosal branch that reaches the facial nerve through the hiatus of its canal and meets the stylomastoid artery; a superior tympanic artery in the canal for tensor tympani; orbital branches through or near the superior orbital fissure that join the lacrimal artery; and temporal branches through the greater wing to the deep temporal arteries. An accessory meningeal artery is present in about half of people.

The frontal branch lies beneath the pterion, where the skull is thin. A blow here can tear it and cause an extradural haematoma, the classic arterial bleed between bone and dura, which needs urgent surgical drainage, usually through a craniotomy. Bleeding below the dura, in contrast, is usually venous. On a side-view radiograph of the skull the arterial grooves can be mistaken for a fracture.

Course and supply

Arises from

The first, mandibular part of the maxillary artery, deep in the infratemporal fossa.

Ends in

Divides inside the middle cranial fossa into frontal and parietal branches that spread over the dura and calvaria.

Supplies

Supplies the dura mater and the bones of the vault, the trigeminal ganglion, the facial nerve in its canal, tensor tympani and, through its anastomoses, parts of the orbit and temporal fossa.