Choosing an Intraocular Lens
When your cataract is removed and a new lens placed inside your eye, patients who have been nearsighted or farsighted can now be made to have excellent vision without glasses. Twenty years ago all patients received the same type of lens during surgery requiring thick eyeglasses or special contact lenses to be able to see. In recent years, new lens technologies have been developed that give additional benefits and choices in determining your lens implant type. The multiple options can make the lens selection a frustrating process, since the IOL inserted with the surgery cannot be “tried on” before the procedure to see which one is best. The two most important things to consider when choosing the artificial lens is the type of lens and the power of the lens.
The choice of lens to use depends on many personal factors, including:
· What activities do you do during the day and which ones would you like to do without glasses if possible?
· At what distance would you like to see most clearly without glasses – near (reading), intermediate (computer screen) or far (driving)?
To determine the power of the lens implant, a series of eye measurements is performed. The measurements are then used in complex mathematical equations to calculate the power of your new lens. Because of variability in biological systems (not every eye is the same), there can be inaccuracies in the formulas.
Today there are several lens options available to patients. You and your doctor will work together to determine the perfect lens for you. These are the current lens types available:
· This high-quality, clear lens delivers excellent vision at only one distance. The focal point or distance at maximum clarity can be set to distance (driving, golfing, watching TV), intermediate (grocery store shelves, computer work, car dashboard), or near (reading, hobbies). There is no extra out-of-pocket cost with a monofocal lens. Most people choose to have their lens set to distance.
· Designed to reduce your need for eyeglasses for both distance and near vision. A series of focal zones or rings is designed into the IOL. Depending on where incoming light focuses through the zones, the person may be able to see both near and distant objects clearly. The lens allows certain eye muscles to move the IOL forward and backward changing the focus much as it would with a natural lens. The ability to read and perform other tasks without glasses varies from person to person but is generally best when multifocal IOLs are placed in both eyes. This is a special lens and it is not fully covered by insurance so there would be an extra payment for them.
· Designed to treat astigmatism and deliver excellent vision at a single distance. This special lens is also not fully covered by insurance.
· This implant technique uses a monofocal lens with a different power in each eye so that you don’t have to use glasses for most of your daily activities. Monovision patients are able to see at a distance and up close without glasses. Your dominant eye is generally set for distance, and the other eye is set for near. Many people successfully use monovision with contact lenses. Successful monovision requires cataract surgery to each eye.
IOLs include filters to protect the eye’s retina from exposure to UV and other potentially damaging light radiation. Your eye doctor selects the filters that will provide appropriate protection for the patient’s specific needs.