SURGICAL-TREATMENT OF PARACLINOID AND OPHTHALMIC ANEURYSMS

Paraclinoid aneurysms include those arising from the ophthalmic segmen t and from the distal cavernous carotid artery or clinoid segment. Thr ee aneurysm variants originate from the ophthalmic segment: ophthalmic artery, superior hypophyseal artery, and dorsal types. Clinoidal segm ent aneurysms arise from the carotid artery in the interval between th e carotid oculomotor membrane proximally and the dural ring distally, and include anterior-lateral and medial variants. With proper exposure and a firm understanding of the parasellar osseous, dural, and vascul ar anatomy, most paraclinoid aneurysms are occluded with low risk to t he brain or visual apparatus.