[citation needed] It passes across the optic nerve (CN II) along with the ophthalmic artery.

It then runs obliquely beneath (inferior to) the superior rectus muscle and superior oblique muscle to the medial wall of the orbital cavity whereupon it emits the posterior ethmoidal nerve, and the anterior ethmoidal nerve.

[1] Branches of the nasociliary nerve include:[1] The branches of the nasociliary nerve provide sensory innervation to structures surrounding the eye such as the cornea, eyelids, conjunctiva, ethmoid air cells and mucosa of the nasal cavity.

Normally both eyes should blink when either cornea (not the conjunctiva, which is supplied by the adjacent cutaneous nerves) is irritated.

[citation needed] This article incorporates text in the public domain from page 888 of the 20th edition of Gray's Anatomy (1918)