As we end this series we want to go over some of the structures of the eye: macula, vitreous body, sclera, choroid, & ciliary body.
The Macula is the central & functional area of the retina. It gives us the ability to see “20/20” and provides the best color vision. The macula takes the picture that is sent to the brain, where vision is completed. The macula provides us with the ability to read and see in great detail whereas the rest of the retina provides peripheral vision. The structure of the macula needs to be undisturbed and relatively dry in order for the images to be clear and vision to be good. The high degree of sophisticated structure in the macula is one of the things that separate man from other beings on earth.
Vitreous Body is the clear gel that fills the space between the lens and the retina. 99% of it consists of water and the rest is a mixture of collagen, proteins, salts and sugars. The vitreous chamber is positioned at the back of the eyeball. It is the largest of the chambers and takes up around 80% of the eye.
Sclera is dense connective tissue of the eyeball that forms the “white” of the eye and surrounds the cornea. The sclera is relatively inactive metabolically and has only a limited blood supply. Some blood vessels pass through the sclera to other tissues, but the sclera itself is considered avascular (lacking blood vessels).
Choroid is the vascular layer of the eye, containing connective tissues, and lying between the retina and the sclera. It is made up of 4 layers and provides oxygen and nourishment to the outer layers of the retina.
Ciliary Body is a circular structure that is an extension of the iris & produces the fluid in the eye called aqueous humor. It also contains the ciliary muscle, which changes the shape of the lens when your eyes focus on a near object. This process is called accommodation.
The eye might be a small organ but it is complex with many structures to make sight possible. Be in awe of your eyes and keep them healthy!