Internal meningeal branch

Dural anastomoses. These can develop between meningeal branches of the internal carotid artery, external carotid artery and vertebral arteries. Occasionally, small dural anastomoses develop between cortical, leptomeningeal and dural arteries. 

The meninges are supplied by branches of the external carotid artery, internal carotid artery and vertebral arteries. The most prominent branches from the external carotid artery are the middle meningeal artery and tributaries of the ascending pharyngeal and occipital arteries. Most of the branches from the internal carotid artery arise near the cavernous sinus and from the ophthalmic artery in the orbit. Branches from the vertebral artery arise at the foramen magnum. There are numerous meningeal anastomoses between these small arteries. 

Fig. 18.3. Final appearance of the external carotid artery. 1, occipital artery 2, ascending pharyngeal artery 3, inferior tympanic artery 4, internal carotid artery 5, lingual artery 6, facial artery 7, posterior auricular artery 8, superficial temporal artery 9, petrous branch 10, middle meningeal artery 11, maxillary artery 12, transverse facial artery...

The ophthalmic artery arises originally from the supraorbital branch of the stapedial artery which later becomes the middle meningeal artery. In addition, the orbital artery will also anastomose with the primitive (and later definitive) ophthalmic artery, from the supracavernous internal carotid artery. Because of the different variants in the involution of the proximal segment of the orbital or ophthalmic arteries, the supply to the orbit will finally arise exclusively from the ICA, the stapedial system (EGA) or both. 

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