After passing through the optic canals, the 2 optic nerves lie superior to the ophthalmic arteries and superior and medial to the internal carotid arteries (ICAs; see Fig 3-3). The anterior cerebral arteries cross over the optic nerves and are connected by the anterior communicating artery, which completes the anterior portion of the circle of Willis. The optic nerves then pass posteriorly over the cavernous sinus to join in the optic chiasm.
Excerpted from BCSC 2020-2021 series: Section 2 - Fundamentals and Principles of Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.