Cataracts are progressive and without treatment, they will get worse until they reach a point where your vision is so poor you can be considered blind. Fortunately, there is an effective solution for cataracts. Cataract surgery removes the clouded lens and replaces it with an artificial alternative - an intraocular lens, or IOL. An IOL is an artificial replacement for the natural lens of your eye. Made from clear plastic, there are several different types, and which is right for you will depend on your individual circumstances.