“With monovision, the eye that sees well for distance vision will be slightly blurred up close and the eye that sees well up close will be slightly blurred when looking at distant objects. With both eyes open, typically vision seems clear at all distances.”
Monovision (sometimes called blended vision) is a visual outcome rather than an actual procedure. It involves an eye surgeon adjusting one eye (usually the dominant eye) for distance vision and the other eye for reading vision. It may at first sound like a strange concept, but the brain plays an important role. Most people who have monovision find that they adjust within a matter of days.
However, monovision is not for everyone and an ophthalmologist, before proceeding with surgery, will usually ‘trial’ patients with a set of contact lenses. There are several ways to achieve monovision, including the same laser eye surgery technique that is used in LASIK laser eye surgery or ASLA laser eye surgery. It can also involve the surgeon implanting intraocular lenses (IOLs), where the power of the implanted lenses is chosen to create monovision.
Correcting one eye for distance and the other for reading creates monovision. When looking into the distance, the brain pays more attention to the eye that is focussed for the distance, and when looking up close, the brain pays more attention to the eye that is focussed for near distances. With monovision, the eye that sees well for distance vision will be slightly blurred up close and the eye that sees well up close will be slightly blurred when looking at distant objects. With both eyes open, typically vision seems clear at all distances.
Not everyone is suitable for monovision, but if you need reading glasses, it may be a viable option to provide good functional vision at distance and near, This will depend on a number of factors, including your age, the type of work you do, and any distance visual error you may have.
The best way to find out if monovision is the right choice for you, the first step is to have an assessment. This includes tests to determine the dominant eye, prescription, thickness of the cornea and the general eye health. If found suitable for monovision, a trial using a set of appropriate contact lenses will most likely be undertaken to ensure that the candidate is comfortable with the concept.
Achieving monovision or blended vision can be done in a number of ways. The most common way is to perform LASIK or an ASLA procedure, where one eye is focussed for distance, and one for near vision. If monovision is being achieved via a surgical lens procedure, one IOL set for distance vision will be implanted, while the other IOL will be set for near vision. In some cases, only one eye will need to be adjusted to create monovision/blended vision.
Not everyone can adjust to the concept of monovision. But for the right people, it is very a successful solution. In fact, several Vision Eye Institute ophthalmologists have had monovision performed with a laser eye surgery procedure.