A cataract is clouding or opacity of the lens inside the eye. It causes gradual blurring of vision and often glares. The Crystalline lens that is located inside the eye behind the iris, the colored part of the eye focuses light on the retina, which sends the image through the optic nerve to the brain.
Conversely, if the lens is clouded by a cataract, light is spreadin such a way that the lens can no longer focus it properly, resulting vision problems. Clouding of the lens occurs due to changes in the proteins and lens fibers.
There is no medicine to prevent or slow cataract progression. In age-related cataracts, changes in vision can be very gradual. Some may not initially recognize the visual changes. However, as cataracts worsen, vision symptoms increase.