Eyeball Anatomy

Eyeball

A bilateral and spherical organ that houses the structures responsible for vision.

Fibrous layer

The outermost layer of the eyeball, consisting of the sclera and cornea, providing shape and support to the eye.

Sclera

The white part of the eye, comprising about 85% of the fibrous layer, providing attachment to extraocular muscles.

Cornea

The transparent front part of the eye that refracts light and is continuous with the sclera.

Vascular layer

The layer of the eye that lies under the fibrous layer, consisting of the choroid, ciliary body, and iris.

Choroid

A layer of connective tissue and blood vessels that nourishes the outer layers of the retina.

Ciliary body

Composed of the ciliary muscle and processes, encircles the eyeball, and controls the shape of the lens.

Accommodation

The process by which the lens changes shape for near vision, facilitated by the contraction of the ciliary muscle.

Iris

The circular structure that gives color to the eye and controls the size of the pupil.

Pupil

The aperture in the center of the iris that regulates the amount of light entering the eye.

Neural layer

The layer of the retina that contains photoreceptors, responsible for detecting light.

Pigmented layer

The layer of the retina that supports the neural layer and is attached to the choroid.

Macula lutea

A yellowish area of the retina with a high concentration of cones for sharp vision.

Fovea centralis

A depression in the macula lutea with a high concentration of cones, responsible for high acuity color vision.

Blind spot

The optic disc, where the optic nerve enters the retina and contains no light-detecting cells.

Aqueous humor

A clear plasma-like fluid that nourishes and protects the eye, filling the anterior and posterior chambers.

Glaucoma

A condition characterized by increased intraocular pressure due to obstructed drainage of aqueous humor.

Vitreous humor

A transparent gel-like substance filling the vitreous chamber of the eyeball, extending from behind the lens to the retina.