What is an IOL and how does it work?
An IOL replaces your natural lens that contains the cataract. An IOL focuses light that comes into your eyes through the cornea and pupil onto the retina, the sensitive tissue at the back of the eye that relays images through the optic nerve to the brain. Most IOLs are made of a flexible, foldable material and are about one-third of the size of a dime.
How will my doctor know which IOL is best for me?
Your IOL will contain the appropriate prescription, or lens power, to give you the best vision possible, much like a prescription you would have for glasses. The appropriate IOL lens power is determined by measuring the curvature of your cornea and the length of your eye. The technology we use to obtain these measurements has improved tremendously in recent years. The information gathered is entered into an in-office computer programmed to calculate your correct implant power. These advances and computer formulations enable our highly experienced surgeons to be more precise in accuracy than ever before in determining IOL implant power.
What are the different types of IOLs available?
The type of IOL implanted will affect how you see when you are not wearing eyeglasses. Glasses may still be needed by some people for some activities. In certain cases, cost may be a deciding factor for you if you have the option of selecting special premium IOLs that may reduce your dependency on glasses.
The following are the different types of IOLs that are available:
Monofocal lens: This common IOL type has been used for several decades. Monofocal IOL, a singular focus lens, are set to provide best corrected vision at near, intermediate or far distances. Most people who choose monofocals have their IOLs set for distance vision and use reading glasses for near activities. On the other hand, a person whose IOLs were set to correct near vision would need glasses to see distant objects clearly. Insurance covers monofocal IOLs.
Multi-focal and accommodative lenses. These newer IOL types may reduce or eliminate the need for glasses or contact lenses. Multifocal IOLs are designed with a series of focal zones or rings. When incoming light focuses through the zones, you may be able to see both near and distant objects clearly. The design of the accommodative lens allows certain eye muscles to move the IOL forward and backward, changing the focus much as it would with a natural lens, to see both at near and distance vision. Each person's success with these IOLs may depend on the size of his or her pupils and other eye health factors. The ability to read and perform other tasks without glasses varies from person to person. However, in recent years, with improvements in technology that enable us to more accurately predict lens power, we have been able to get more and more patients independent from glasses. These premium lenses are not covered by insurance. Talk to your OCB eye doctor about your unique situation and whether these lenses are an option for you.
Toric IOL. This is a monofocal IOL, with astigmatism correction built into the lens. Astigmatism distorts or blurs the ability to see both near and distant objects. The cornea of a person with astigmatism is oval in shape and requires more optical correction. People with significant degrees of astigmatism are usually very satisfied with toric IOLs. Insurance does not cover this type of IOL. There are other alternatives to correcting astigmatism such as glasses or contact lenses after surgery that your OCB eye doctor can discuss this with you.