last updated 19-03-2024

Anatomy of the eye

Anatomy of the eye

The eye focuses images of the outside world onto the neural tissue of the retina, which converts the images into electrical signals that are perceived in the brain. The cornea and sclera form the outside of the eye. The cornea is transparent and contains fine sensory fibers. The sclera is the continuation of the cornea and forms the protective coat of the eye. The uveal tract is the layer beneath the sclera formed by iris (pigmented smooth muscle), ciliary body, and choroid (vasculature beneath the retina).

When light enters the eye, it passes through the cornea, anterior chamber, and pupil. The pupil size is controlled by the autonomic nervous system in response to lighting conditions. After passing through the pupil, the light will enter the posterior chamber and hit the back of the eyeball, which is composed of different tissue layers. First, there is a layer of retinal blood vessels, then a layer of photoreceptors (retina). The retinal cells translate the signal into electrical signals, which leave the eye via the optic nerve.

The eye is embedded in the eyelids, conjunctiva, and musculature. Six extraocular muscles controlled by cranial nerves move the eyeball.