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Retina

The light-sensitive tissue lining at the back of the eye. The retina converts light into electrical impulses that are sent to the brain through the optic nerve.

PubMed Health Glossary
(Source: NIH - National Eye Institute)

A diagram of the anterior (front) and posterior (back) segments of the eye. The parts of the eye are labeled. Click to enlarge

Parts of the inside of the front and back of the eye NIH Medical Arts

Terms to know

Anterior
In human anatomy, has to do with the front of a structure, or a structure found toward the front of the body.
Chamber
An enclosed space.
Choroid
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white outer layer of the eye) and the retina (the inner layer of nerve tissue at the back of the eye). The choroid is filled with blood vessels that bring oxygen and nutrients to the eye.
Ciliary Body
A part of the middle layer of the wall of the eye. The ciliary body includes the ring-shaped muscle that changes the size of the pupil and the shape of the lens when the eye focuses. It also makes the fluid that fills the eye.
Conjunctiva
A membrane that lines the inner surface of the eyelid and also covers the front part of the eye. Conjunctivitis is inflammation of the conjunctiva.
Cornea
The transparent part of the eye that covers the iris and the pupil and allows light to enter the inside.
Eye
Eyes are the organs of vision. They detect light and convert it.
Eyelid
An eyelid is a thin fold of skin that covers and protects the eye.
Iris
The colored tissue at the front of the eye that contains the pupil in the center. The iris helps control the size of the pupil to let more or less light into the eye.
Lens in the Eye
A clear disk that focuses light, as in a camera or microscope. In the eye, the lens is a clear, curved structure at the front of the eye behind the pupil. It focuses light rays that enter the eye through the pupil, making an image on the retina (light-sensitive layers of nerve tissue at the back of the eye).
Limbus
A border of an anatomical part, such as the edge of the cornea.
Macula of the Eye
The part of the retina in the eye used for reading and seeing fine detail.
Optic Disc (Blind Spot)
Optic disc, also known as the anatomical blind spot, the specific region of the retina where the optic nerve and blood vessels pass through to connect to the back of the eye.
Optic Nerve
A bundle of more than 1 million nerve fibers that carries visual messages from the retina to the brain.
Ora Serrata
The ora serrata (of the eye) is the serrated junction between the retina and the ciliary body.
Pars Plana
The pars plana is part of the uvea, one of the three layers that comprise the eye.
Posterior
In human anatomy, has to do with the back of a structure, or a structure found toward the back of the body.
Pupil
The opening at the center of the iris. The iris adjusts the size of the pupil and controls the amount of light that can enter the eye.
Sac
A bag or pouch inside a plant or animal that typically contains a fluid.
Sclera (White of the Eye)
The white layer of the eye that covers most of the outside of the eyeball.
Trabecular Meshwork (Trabeculum)
The trabecular meshwork is an area of tissue in the eye located around the base of the cornea, near the ciliary body. It is responsible for draining the aqueous humor from the eye via the anterior chamber (the chamber on the front of the eye covered by the cornea).
Vasculature
The arrangement of blood vessels in the body, or within an organ.
Vitreous Humor (Vitreous Body)
The clear jelly-like substance that fills the inside of the eyeball. As a person ages, the vitreous humor becomes more liquid.

Terms to know

Anterior
In human anatomy, has to do with the front of a structure, or a structure found toward the front of the body....
Chamber
An enclosed space....
Choroid
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white out...
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