Blended Vision - Laser Eye Surgery Guide

Blended vision (or monovision) is a surgical method of treating the issue of long-sightedness (hypermyopia) in one eye and short-sightedness (myopia) in the other eye. This procedure is also used in the correction of presbyopia, which is the long-sightedness that affected everyone as we age. This is especially an issue after middle age.

Presbyopia occurs because at middle age, the muscles in our eyes harden and become less elastic. This means that their focussing power is lost so it becomes more difficult to see objects that are near to us. It is especially noticeable when trying to read or use a computer.

The most common form of treatment for presbyopia is by purchasing glasses or contact lenses. The types of lenses available for the issue are varifocal (or bifocal) as well as monovision (where the lenses are different – one helps resolve long-sightedness whereas the other resolves short-sightedness).

Blended vision

If glasses or contact lenses do not appeal to you, then you may wish to consider the more innovative solution of Blended Vision or LASIK Monovision surgery. This procedure employs the use of a laser to correct your vision defects.

The first step of the surgery involves the surgeon determining which of your eyes is dominant and which on is weaker. Once this has been discovered, the surgeon will proceed to operate on the weaker eye. They will force this eye into becoming short-sighted so that you can see near objects more clearly.

Your dominant (or strong) eye will be left alone so that you maintain the ability to see objects that are far away. However, the eye may be worked on if you also have a problem with your distance vision.

The result of the blended vision procedure is that one of your eyes now has the ability to see nearby objects, whereas the other is able to view things that are further away. Your brain can quickly adjust to blend the two images together so that you are able to see the full picture clearly, explaining the name "blended vision".

The new adjustment required can take some people a while to get used to. However, it will happen so you just have to persevere. If you have any concerns then contact your doctor or surgeon.

Am I a suitable candidate for the blended vision procedure?

You will be required to attend a consultation prior to undergoing the procedure. Here, the surgeon will assess you and they will conclude with whether they feel that you are a suitable candidate for the surgery.

A number of factors will be concerned when determining your suitability including your health, lifestyle, expectations and justification for wanting the surgery.

Generally speaking, if you have healthy eyes and you vision is good when wearing your glasses, then this surgery will probably be a beneficial option for you.


Presbyopia is a condition that affects you at middle aged. It tends to confer the requirement for reading glasses, although your distance vision will usually remain intact.

If, up until middle age, you vision has been completely normal, then you will most likely only need to have one eye worked on during the blended vision surgery.


If you are short-sighted then you will have problems with seeing objects that are quite a distance away, however visualising nearby things will not be an issue. You will probably also find that you are perfectly capable of reading without wearing your glasses.

If you suffer from being short-sighted, then this procedure could produce good results for you.


If you suffer from being long-sighted then you will see objects far away absolutely fine, however you will struggle to see things that are near to your eyes. This is often a problem with trying to read.

If you are long-sighted then you will require treatment of both of your eyes. During the procedure, the surgeon will make your stronger eye better for distance vision and will treat your weaker eye so it becomes short-sighted. This will create a vision balance that can be resolved by the brain.


If you suffer from astigmatism then you will notice that your vision is blurry regardless of whether you are long- or short-sighted. To correct this, you will require treatment for both of your eyes.

The results of the procedure

The surgery is aimed at eliminating the requirement for glasses in order to read and perform other 'close up' tasks. In general, this procedure is successful although some patients discover that they still require glasses for some activities, such as night driving.