Mono-vision Treatments

Monovision is a compromise and not everybody likes it. Some people will take to it quickly while others will take a considerable amount of time before they get used to it. Acquiescence is necessary and Monovision or Mini-Monovision will not suit the impatient, the depressive or the perfectionist person. Those who can relax and wait for their brain to adjust to Monovision can reap the rewards and will be delighted with their new found vision. You need the right attitude to get used to Monovision and as you will read later, it is a compromise which works wonderfully for most patients.

It can take one to three months for your vision to stabilize. In general, the greater your pre-procedure prescription, the longer it will take to stabilize. You should not be concerned if in the days following your surgery, you do not have the reading ability that you thought you would. The procedure, by design, will often give a little bit more correction and then slip back to the intended prescription in the days and weeks following surgery. You may therefore require a temporary pair of reading glasses to work.

Monovision or Mini-Monovision in contemporary laser eye surgery reduces spectacle dependence and is well tolerated, but involves compromises for the quality of distance vision. Remember, Mono-vision is not perfect. Mono-vision is a compromise that will enable you to have distance near vision without correction, but the quality of the vision will likely not be as sharp as with your glasses or contact lenses. It requires adaptation, which may require several weeks, up to several months to fully adjust. During this adjustment period, each eye may sometimes interfere with the other, and depth perception may sometimes seem off, but these problems gradually resolve. If after three months you feel mono-vision is not working for you, the nearsighted eye may be enhanced for distance correction. You will then need reading glasses for all near tasks.

A: Mono-vision LASIK/PRK (-1.00D to -2.00D)

Spectacle independence for distance vision is the central aim in modern laser eye surgery. This leads to high levels of patient satisfaction, but spectacle dependence for reading and other near vision tasks is the usual result in clients in the 40-45 year age group and beyond.

It is important that you understand that refractive surgery DOES NOT PREVENT aging of the eyes which causes the loss of the eye’s ability to focus on near objects (to see objects clearly which are closer than arm’s length away from you). This process is called PRESBYOPIA (literally it means ‘old vision’). So, if you are over 40 and have both of your eyes fully corrected for distance vision (Driving and watching TV), you will eventually become more and more dependent upon reading glasses for near vision.

One technique available to surgeons to reduce spectacle dependence for near vision is to target a spread of focus (good far sight in 1 eye along with some degree of low myopia in the other eye) after refractive laser eye surgery. This is known as monovision.

Monovision can also be created by using contact lenses. In contact lens wearers, a review of the literature reports patient satisfaction at 76%. Several studies reported the outcomes of monovision following laser refractive surgery where -1.25-2.0D of myopia was targeted. They report satisfaction rates of 88%. Only 2.4% of patients requested reversal of their monovision following refractive surgery.

Our Aim in creating Monovision:

• To leave patients with corneal astigmatism <1D in the monovision eye
• Perform monovision on the dominant eye where possible
• We aim for -0.5 – 2.0 D myopia (Monovision)

Also, if you are nearsighted, over the age of 40, and accustomed to removing your glasses for close work, you need to give extra thought to vision correction surgery.

Those patients who do not use monovision will simply wear reading glasses for near work when the time comes. It may take 3 to 4 weeks for patients who are first exposed to MONOVISION to get used to it, however some can never adapt.

One should consider that presbyopia is a progressive condition that starts at around age 40 and continues into the mid-60’s. Every few years, the ability to focus on close objects lessens, requiring an increase in the amount of near vision correction. So, while at age 45, -1.50 may be perfect for reading, it may be inadequate by age 55 when -2.25 may be needed. There is still a great benefit to having some amount of under-correction since patients with -1.50 will continue to have good mid-range vision in later years. Consider that many of the things that you do like looking at your dashboard, seeing the food on your plate, reading a menu in a restaurant or a label on a can are all mid-range tasks.

B: Mini-Monovision (-0.50D to -0.75D)

If you are approaching the age of 40, or are older, we would like to recommend MINI-MONOVISION as an option.

Instead of leaving one eye undercorrected to the full correction needed to be able to see close objects sharply, only a slight undercorrection is left (about -0.50 to -0.75D of power or 20/30-40 vision up close). Most patients will tolerate the small discrepancy between eyes without noticing it. This is easily demonstrated at the time of your pre-operative evaluation.

One advantage to MINI-MONOVISION is that it delays the age at which an individual becomes dependent upon reading glasses until later in the 40.s. It is also designed to make all of the mid-range tasks easier as well.