A detached retina occurs when the retina is moved from its normal position in the eye. It requires immediate medical care if permanent vision loss is to be prevented. Risk factors for the condition include diabetes, older age, or an eye injury. Possible symptoms include "floaters," flashes of light, or partial vision loss.
The retina is the light-sensitive layer of tissue that lines the inside of the eye and sends visual messages through the optic nerve to the brain. When the retina detaches, it is lifted or pulled from its normal position. If not promptly treated, a detached retina can cause permanent vision loss.
In some cases, there may be small areas of the retina that are torn. These areas, called retinal tears or retinal breaks, can lead to retinal detachment.
In order to understand a detached retina, it is helpful to understand the parts of your eye involved with sight. These structures include the:
Your cornea is a thin, clear layer on the outside of your eye. The iris, or the colored part of your eye, is a muscle that controls the amount of light going through your pupil, or the round opening in the center of your eye. Behind the iris sits the lens, which is just larger than your pupil. The iris is enclosed by a thin, clear capsule that holds the lens in its proper place.
When light enters your eye, the cornea and lens form the light rays into a beam of light that is focused directly onto your retina -- the light-sensitive tissue at the back of the eye. The retina instantly converts light, or an image, into electrical impulses. The retina then sends these impulses, or nerve signals, to the brain through the optic nerve. The optic nerve is a bundle of more than one million nerve fibers connecting the retina to the brain.
The macula is located in the center of the retina. It is made up of millions of light-sensing cells that help to produce central vision.
Most of the eye's interior is filled with vitreous, a gel-like substance that fills about 80 percent of the eye and helps it maintain a round shape. The vitreous contains millions of fine fibers that are attached to the surface of the retina.