Monovision for Presbyopia
Many people use reading glasses to correct presbyopia, the age-related loss of close-up focusing ability. They use their eyeglasses for reading and other close work, taking them off when looking at objects that are farther away, or they use bifocals for clear distance and near vision.
Standard refractive surgery procedures do not correct presbyopia. Monovision is a specialized refractive surgery technique that enables one eye to focus at close proximity, while the other eye is left untreated or, if needed, treated for clear distance vision. Having each eye focus at different distances can reduce or eliminate the need for eyeglasses or contacts. It may seem difficult to get used to this, but about six to eight weeks after the monovision procedure, the brain is able to adjust to the two eyes’ different focusing ability. Usually, this surgery is performed only after a successful trial of monovision using glasses or contact lenses.
The refractive procedures most commonly used to treat presbyopia are laser-assisted in situ keratomileusis (LASIK) and conductive keratoplasty (CK).
With LASIK, your ophthalmologist (Eye M.D.) will use an excimer laser to reshape your cornea to correct your dominant eye for distance vision and will leave your other eye slightly nearsighted, so that you can use that eye for close-up vision.
Conductive keratoplasty is a minimally invasive thermal refractive procedure. Your ophthalmologist uses a tiny probe that releases controlled amounts of radio frequency (RF) energy to apply heat to the peripheral portion of the cornea. The heat then causes the sides of the cornea to shrink and to tighten like a belt, increasing the steepness of the central cornea and its optical power. This refocuses light rays on the retina and improves vision. Your ophthalmologist will use CK to correct your dominant eye for distance vision and leave your other eye slightly nearsighted.
In addition to these procedures, other refractive procedures may be used to correct presbyopia, including the following:
• laser thermal keratoplasty (LTK);
• scleral expansion bands (SEBs);
• refractive lens exchange (RLE); and
• multifocal LASIK (presby-LASIK).
Be sure to discuss your options with your ophthalmologist to choose the best refractive procedure for your needs, if surgery is a good option to correct your presbyopia. It may be best to test monovision with contact lenses before you opt for refractive surgery to be sure you will be comfortable with the adjustment following surgery and will achieve the results you desire.
As with any surgery, there are certain risks associated with LASIK, CK, and other refractive procedures. Be sure to discuss these possible risks with your ophthalmologist.