A cataract is a clouding of part or all of the lens inside the eye. This clouding interferes with light reaching the retina at the back of the eye, resulting in general loss of vision. Causes include aging, long-term exposure to the sun’s ultraviolet radiation, injury, disease and inherited disorders. If the eye is healthy, a cataract can be surgically removed. Usually, an intraocular lens implant is inserted in the eye, and vision is restored. Cataract surgery has a high success rate in otherwise healthy eyes. However, cataract surgery is not always possible for people who also have other eye diseases. These people may require low-vision rehabilitation to maximize their remaining vision.