The lens of the eye plays an important role in focusing images on the retina. If the lens loses clarity, as it does when a cataract develops, light rays do not focus clearly, and the image is blurry. Glasses or contacts cannot sharpen vision if a cataract is present and focus is only restored by removing the cloudy lens and replacing it with an intraocular lens (IOL). Here are a few IOLs that are available to you.
IOLs have many advantages. Unlike contact lenses, which must be removed, cleaned and reinserted, IOLs require no care and become a permanent part of the eye. Rapid evolution of IOL designs, materials and implant techniques has made them a safe and practical way to restore normal vision following cataract surgery.
Early IOLs were made of a hard plastic material, and these lenses are still used in certain situations. Newer generation IOLs are soft, foldable lenses made of acrylic or silicone. Because of their flexibility, the lenses can be rolled and inserted into a smaller incision, resulting in a shortened recovery time following surgery. When replacing the natural lens following cataract surgery, two types of IOLs are used:
Monovision (Cataract surgery)
Standard cataract surgery involves placing a monofocal intraocular lens into the eye after the cataract is removed. This would mean that a decision has been made to focus the eye without glasses at a certain focal point. The typical options for focus point after cataract surgery are distance vision (activities such as driving), intermediate vision (activities such as computer work or cooking), or near vision (activities such as reading). When choosing one out of these three focus points, the patient is often left with a need for glasses at the other two focus points. Some patients may choose to have monovision where one eye is focused for distance and the other eye is focused for a near target to give a greater depth of focus. This is not an option for everyone and should be discussed with your surgeon.
Conventional IOLs are monofocal, correcting vision at one distance only. Following surgery, glasses or contacts must still be worn to achieve clear, multifocal vision.
Multifocal or Accommodating IOLs
Multifocal or Accommodating IOLs are the newest generation of intraocular lenses. Unlike monofocal IOLs, multifocal IOLs correct the full range of vision, generally eliminating the need for glasses or contacts following cataract surgery. You and your doctor can decide what lens is right for you.