The human eye functions like a camera. If the lens of the camera is soiled or smeared with grease, a very hazy picture will result. A cataract is the clouding of a clear transparent lens inside the eyeball. This clouding prevents the image from being focused on the back of the eye.
A cataract is the most important cause of blindness all over the world. Although it occurs commonly in old people, yet it can appear at any age. According to one of our surveys, 15-20% of blindness in children is because of cataracts.
The World Health Organization estimates that 180 million people suffer from severe visual impairment (legally blind, by U.S. standards). The leading cause of blindness throughout the world is cataracts and 90% of this blindness is found in the developing world.