As part of our visual (sight) system, each
eye contains a lens. The lens is a clear, disc-shaped
structure behind the pupil and iris. The lens focuses light beams on the retina, the back part of the eye that sends sight signals to the brain. When
the lens becomes cloudy, vision blurs. Clouding of the lens is called a cataract.
Cataracts are common, especially in older individuals. As a normal part
of the aging process, the lens gradually becomes cloudy. A simple eye examination
by an ophthalmologist (eye physician) can detect
a cataract.
The July 9, 2003, issue of JAMA includes an article about cataracts.