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Cataracts are cloudy patches in the lens (the transparent structure at the front of the eye) which can make vision blurred or misty and can develop in one or both eyes.
Over time, the cloudy patches can become bigger and more of them can develop. As less light is able to pass through the lens, a person's vision is likely to become blurry or cloudy. The cloudier the lens becomes, the more a person's sight is affected.
In younger patients, cataracts may be caused by diabetes, eye injuries or other conditions of the eye, such as uveitis. In older patients, age-related changes in the lens can lead to cataracts. Both genetic and environmental factors may play a part.
In most cases, a cataract will continue to develop and surgery to remove the cataract is the only way to restore vision.