The middle meningeal artery is typically the third branch of the first part (retromandibular part) of the maxillary artery; one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries which supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. In approximately half of subjects it branches into an accessory meningeal artery. The middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma. [ http://en.wikipedia.org/wiki/Middle_meningeal_artery ]