Cataract

Clouding of the lens of the eye that results in obscured vision.

Organ or part of body involved: Eye lens
Symptoms and indications: A painless blurring of vision; glare, or light sensitivity; poor night vision; double vision in one eye; needing brighter light to read; and fading or yellowing of colors.
Causes and risk factors: The exact cause is unkown. Aging, diabetes, glaucoma and detachment of the retina, injury to the lens, drugs, and high doses of radiation.
Prevention: Protection from excessive sunlight may help slow the progression of cataracts. Sunglasses that screen out ultraviolet (UV) light rays or regular eyeglasses with a clear, anti-UV coating offer this protection.