Cataracts occur when the lens of the eye becomes cloudy or misty, similar to the effect of looking through frosted glass. The lens sits just behind the pupil and is usually transparent, allowing light to pass through to the retina.
Cataracts are the primary cause of vision loss for people over 40 and the leading cause of blindness in the world.
The lens of the eye is composed of water and protein; the protein arranged naturally, keeps the lens clear. Cataracts cause the protein to clump together and produce a cloudy appearance in a small part of the lens. Over time, this can grow larger, making it more difficult to see.
Cataracts usually appear in both eyes; however, they may not necessarily develop at the same time.