An intraocular lens (IOL) is an artificial replacement lens implanted when a patient's natural lens has been surgically removed during cataract surgery. A wide variety of replacement lenses is available to cataract patients. Each type of lens has its own advantage for post-surgery vision, The most effective lens to use depends on the patient's preferences and particular vision goals, which can differ according to individual occupations and lifestyles. IOLs often eliminate the need for glasses or contacts after cataract surgery, conveniently providing most patients with clear vision.
Multifocal Intraocular Lenses
Multifocal intraocular lenses are designed to correct vision at varying distances. They are appealing to those who would prefer not to wear eyeglasses or contact lenses after surgery, or to require corrective lenses only for certain activities.
AcrySof® IQ ReSTOR® Multifocal Toric Intraocular Lens
The AcrySof® IQ ReSTOR® multifocal toric intraocular lens provides good correction for near, intermediate and distance vision. Its biconvex optic is shaped during a process known as apodized diffraction, which provides an increased depth of focus. Unlike other IOLs that are made of silicone or hard plastic, the AcrySof IQ ReSTOR multifocal toric IOL is made of soft, foldable acrylic. As a result, inserting it requires only a small incision that does not need to be closed with stitches. It corrects for both cataracts and presbyopia (age-related farsightedness), and filters blue light without affecting vision quality.
ReZoom® Intraocular Lens
The ReZoom® multifocal intraocular lens is a state-of-the-art clear, flexible implant that can be used in patients with or without presbyopia who want to have near, intermediate and distance vision without relying on glasses or contact lenses. The ReZoom lens features five spherical segments, and provides smooth transitions so the eyes can change focus seamlessly. The center of the lens is optimized for bright light and distance vision, while the fourth zone supports near-vision in a variety of light conditions. The outermost zone accommodates for low-light distance vision. The ReZoom IOL is also specially designed to reduce internal reflections and minimize glare.
Tecnis® Multifocal Intraocular Lens
The Tecnis® multifocal intraocular lens can also be used for those patients with or without presbyopia who want to have near, intermediate and distance vision without relying on glasses or contact lenses. Designed to provide a cataract surgery patient with high-quality vision similar to that of a younger person's, the Tecnis IOL improves functional vision, the ability to see objects in varying light conditions, especially at night and twilight, and in rain, snow or fog. It provides improved night vision and a reduction of spherical aberrations (scattering of light), a common side effect of cataract surgery.
Unlike other multifocal IOLs, the Tecnis Multifocal IOL provides excellent vision at all distances and at all light levels. Approximately 90 percent of patients using Tecnis Multifocal IOLs do not require reading glasses.
Each type of multifocal IOL has its advantages. The ophthalmologist, in consultation with the patient, decides which IOL is appropriate.
Accommodative Intraocular Lenses
Accommodation is the ability to shift focus between near and distant objects, providing sharper vision at multiple distances in order to minimize the use of glasses.
The most commonly used accommodative intraocular lens is the Crystalens IOL, the only FDA-approved presbyopia-correcting intraocular lens. The Crystalens IOL is made with flexible silicone that has hinges on each side, allowing it to move with the eye muscle, flexing and accommodating seamlessly so the patient can focus on surrounding objects at any distance.
Toric Intraocular Lenses for Astigmatism
Until recently, a patient with astigmatism did not have the same opportunities as other cataract patients to have vision corrected with IOLs. Typically, an astigmatic patient would require an additional surgical procedure, such as LASIK, to correct vision after cataract surgery. If the patient did not want to undergo another surgical procedure, the only option for correction would be wearing contact lenses or glasses.
Toric IOLs, however, are specially designed to correct for astigmatism when implanted during cataract surgery. They provide complete vision correction from a single surgical procedure.