- A cataract is a clouding of the lens in the eye that can cause vision loss. It is often related to aging but may be caused by other factors like smoking. - Symptoms include decreased vision, glare from lights, and frequent changes to prescriptions. Cataract surgery is usually done to replace the cloudy lens with an artificial lens implant. - There are different types of intraocular lenses that provide varying levels of vision correction and independence from glasses after surgery. Conventional lenses correct one distance while newer lenses aim to provide multifocal vision.