Monovision

Monovision entails using LASIK or surface treatment (PRK/LASEK/ EPi-LASIK) to correct one eye for distance vision and the other eye for near vision. Many refractive surgery patients are in the presbyopic age group, and these patients often experience difficulties with near vision after their myopia is corrected. Preoperatively, many of these patients are able to read by taking off their glasses; postoperatively, they may find they are no longer able to do so. Most patients choose to undergo refractive surgery to decrease their dependence on glasses and are therefore not happy with the prospect of needing reading glasses.

Monovision is one way of addressing the presbyopia problem by fully correcting one eye for distance (usually the dominant eye) and undercorrecting the other eye by 1 to 2 diopters. The near-vision eye may be placed in focus at a reading distance (33 cm) or at an intermediate distance (for example, at 50 cm for computer use). This approach has been used to address the presbyopia problem, where patients in the presbyopic age group experience difficulties with near vision after their myopia (distance vision) is corrected. Patient satsifaction rate with monovision was estimated to be 88% (Jain, 2001).
However, not every patient is a good candidate for monovision. Some patients might not be able to adapt to it and accept that the image, at any given distance, will be blurred in one eye and in focus in the other eye.

References and additional reading:

Jain S, Ou R, Azar DT. Monovision outcomes in presbyopic individuals after refractive surgery. Ophthalmology. 2001;108(8):1430-3.

Sippel KC, Jain S, Azar DT. Monovision achieved with excimer laser refractive surgery.
Int Ophthalmol Clin. 2001;41(2):91-101.  

Jain S, Arora I, Azar DT. Success of monovision in presbyopes: review of the literature and potential applications to refractive surgery. Surv Ophthalmol. 1996;40(6):491-9.