patient education

basic facts about your eyes

The eye works like a camera. The lens inside a camera focuses the light coming in from the outside world onto film. Similarly, light first enters the eye through the cornea, which is the clear front part of your eye. The light then passes through the lens of the eye, and is focused onto the retina. The retina is located at the back of the eye and functions just like the film in a camera. After the retina captures the image, the signals travel from the eye to the brain along the optic nerve. The optic nerve plugs into the back of the eye and functions like a cable that takes signals to a television set. The brain then processes the signals and this is what allows us to see.

There are many conditions that may impair the proper functioning of your eyes. For example, dry eyes can irritate the cornea, causing discomfort. When the lens of the eye grows cloudy it is called a cataract, which can diminish vision. In a condition called glaucoma, the optic nerve is damaged because the eye pressure is too high. Problems like macular degeneration and diabetes can affect the retina, also resulting in blurry vision. The reduction in vision from these diseases often progresses gradually and without warning, and can lead to severe vision impairment if left untreated.

Your eyes are delicate and precious parts of your body, and it is important to treat any problems sooner rather than later. Eye pain, redness, or blurry vision will sometimes alert you that something is wrong with your eyes. However, many times there are serious eye problems that start with no symptoms and can progress to severe reduction in vision without warning. For this reason, even if you have no eye complaints, we recommend periodic eye examinations to detect and correct any sight-threatening problems that may be developing.

Diagram courtesy of the National Eye Institute, National Institutes of Health