A variety of periorbital ossifications are commonly found in "normal" human skulls (Kostowiecki, 1964). They are located predominately in the posterior part of the orbit and display various shapes and sizes. The most common ossifications, apart from the "spina recti lateralis," appear in the superior orbital or sphenoidal fissure. Some of them represent small, free pieces of thin bone located at the junction of periorbital and dural layers. Others grow upwards from the superior margin of the greater sphenoidal wing, which forms the lower margin of the lateral extension of the superior orbital fissure. Spicules which appear near the lateral end of the superior orbital fissure may embrace a sizeable foramen. This opening carries the superior ophthalmic vein as well as the arterial meningeo-orbital anastomosis between the lacrimal artery and the anterior ramus of the middle meningeal artery. The name "medial meningeo-orbital foramen" has been previously proposed for this aperture.
MARJAN KOSTOWIECKI, MICHAEL HARTY. Progressive Obliteration of the Superior Orbital Fissure. Arch Ophthalmol. 1965;74(1):86–90. doi:10.1001/archopht.1965.00970040088021
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