Multifocal Lens Implants
Advancement in intraocular lens (IOL) technology is ongoing and rapid. Whereas in the past the goal of cataract surgery was to improve the best vision attainable with glasses, now we strive to reduce dependence on glasses or eliminate them altogether. There is, however, still no guarantee of being spectacle-free after cataract surgery.
The ability of the eye to see clearly at both distance and near requires the lens of the eye to slightly change shape and position. This is called accommodation. We are born with a generous accommodative power that gradually decreases throughout life. Between the ages of 40 and 50 most people have lost enough accommodative power to require some assistance with reading in the form of reading glasses or bifocals.
Once the lens of the eye is removed in cataract surgery, the ability to accommodate is lost. Based on calculations made prior to surgery, an IOL of the appropriate power is placed to correct either distance or near vision. This requires that patients still wear glasses either to read or to drive. One way around this problem is to correct one eye for distance and one eye for near. This is called monovision, and although it takes some getting used to, many patients are happy with this option.
The latest tools in combating this problem are the multifocal lens implants. These IOL's have the ability to correct both distance and near vision in a single lens. These lenses are not suited for everyone, however. For example, pre-existing corneal or retinal problems may prevent a patient from being a good candidate for a multifocal lens implant. After proper consultation, you and your ophthalmologist should be able to choose the most appropriate type of IOL for your needs.