AAPECS : How the Eye Works

757.552.0800

Correction Procedures :
How the eye works

The Normal Eye
Your eye focuses light to form images or "pictures", very much like a camera. As light enters the eye, it is focused by both the cornea and the lens to create a clear image on the retina. Your eye changes these images into electrical signals, which are then sent to your brain. If your eye is out of focus, what you see will be blurred.

The Nearsighted Eye (Myopia)
Myopia is the most common refractive condition, affecting one in four people in North America . Myopic individuals are nearsighted: they see near objects clearly, but distant objects are blurry. Myopia occurs when the cornea and lens focus the light in front of the retina instead of exactly on it.

Nearsightedness can be corrected by:

• Adding a third lens to the systemlike a contact lens or glasses, which helps focus the light onto the retina. (Work is currently being done on development of a lens that is implanted into the eye instead of being worn over the eye.)

• Changing the power of the lens.The lens can be replaced should it become damaged or cloudy (Cataract) and a new lens of a more appropriate power can be implanted in the eye to reduce or eliminate myopia.

• Changing the power of the cornea.Flattening the cornea will help focus light rays further toward the back of the eye. There are numerous techniques for changing the shape of the cornea. The most common of these are Radial Keratotomy (RK), INTACS, and Laser Assisted In Situ Keratomilieusis (LASIK).

The Farsighted Eye
Farsightedness occurs when light rays entering the eye are focused behind your retina instead of directly on it. The tendency to develop farsightedness runs in families. Farsightedness usually starts in childhood and typically stabilizes in the late teens or early adulthood.

The Astigmatic Eye
In the astigmatic eye, the front surface of the cornea is irregularly shaped. This will cause the light rays to be focused in different planes.

In myopic (nearsighted) astigmatism, all of the light rays are focused in front of the retina. This condition allows the patient to see near objects significantly better than distant objects. However, no objects will be in perfect focus.