Cataracts
A cloudiness or opacification of the lens is called a cataract. Cataracts can occur at any age--in fact, babies can be born with them--but they are most common later in life.
About 50 percent of people ages 65 to 74 and 70 percent of those 75 and older have cataracts. In 2004, an estimated 20.5 million Americans over 40 (approximately 17 percent) had a cataract; that number is expected to reach 30.1 million by 2020. However, not all cataracts affect vision significantly or require treatment.
About 1.5 million cataract surgeries are performed each year in the United States. Surgery is the only way to cure cataracts.
The cloudy lens is removed from the eye and replaced with a permanent intraocular lens implant (click on lens implants for more information)
What is the Lens?
The lens is a clear part of the eye that helps to focus light, or an image, on the retina. The retina is the light-sensitive tissue at the back of the eye.
In a normal eye, light passes through the transparent lens to the retina. Once it reaches the retina, light is changed into nerve signals that are sent to the brain.
The lens must be clear for the retina to receive a sharp image. If the lens is cloudy from a cataract, the image you see will be blurred.
CATARACT SYMPTOMS AND SIGNS:
A cataract starts out small, and at first has little effect on your vision. You may notice that your vision is blurred a little, like looking through a cloudy piece of glass or viewing an impressionist painting. A cataract may make light from the sun or a lamp seem too bright or glaring. Or you may notice when you drive at night that the oncoming headlights cause more glare than before. Colors may not appear as bright as they once did.
The type of cataract you have will affect exactly which symptoms you experience and how soon they will occur. When a nuclear cataract first develops it can bring about a temporary improvement in your near vision, called "second sight." Unfortunately, the improved vision is short-lived and will disappear as the cataract worsens. Meanwhile, a sub capsular cataract may not produce any symptoms until it's well-developed.