Around the age of forty, most people experience a change in vision in which they are no longer able to focus on near objects, such as restaurant menus, medicine bottles, and computer screens. This condition is called presbyopia.
Presbyopia occurs when the crystalline lens inside the eye begins to thicken, and lose its flexibility. This is a natural part of the aging process, but can be quite frustrating.
Many times presbyopia is corrected by bifocal or multi-focal spectacles, or multi-focal contact lenses. Both of these options can be expensive, and do not work for every patient. If a person does not want to wear glasses, and doesn’t want to incur the costs of multi-focal contact lenses, there is another, typically far less expensive option, called monovision correction.
Cheaper Than Multifocal Lenses
Monovision contact lens correction works by correcting one eye for distance viewing, and the other eye for near viewing. Your eye doctor or technician will help you determine which of your eyes is more dominant, and in most cases, this will be the eye that is corrected for distance.
After both contact lenses are inserted, the eye corrected for distance will experience a slight blur when viewing objects or print that are close, and the eye corrected for near will experience some blur when viewing objects at a distance. However, with both eyes open, this blur is normally minimal. Over time, this blur becomes less noticable, because the brain adapts to the new correction.
Monovision Lenses Are Not For Everyone
There are a few possible downsides to monovision correction. Some patients find that even with extended wear, they are not able to adjust to the eyes being corrected for different distances, and that both distance and near acuity are not acceptable. At this point, they will either have to purchase multi-focal glasses or contact lenses in order to correct their vision for both distance and near viewing.
Monovision correction can also affect depth perception slightly. Only a small percentage of patients experience enough of a change in their depth perception to discontinue wear.