Several muscles working together move the eye, allowing people to look in different directions without moving their head. Each eye muscle is stimulated by a specific cranial nerve (see Cranial Nerve Disorders: Overview of the Cranial Nerves). The optic nerve (a cranial nerve), which carries impulses from the retina to the brain, as well as other cranial nerves, which transmit impulses to each eye muscle, travel through the orbit.

An ophthalmic artery and a central retinal artery (an artery that branches off of the ophthalmic artery) provide blood to each eye. Similarly, ophthalmic veins (vortex veins) and a central retinal vein drain blood from the eye. These blood vessels enter and leave through the back of the eye.

Last full review/revision August 2006 by James Garrity, MD