Monovision is a treatment technique used to treat presbyopia that usually requires a corrective contact lens being worn so that one eye is used for distance vision and the other is used for near vision.
If you are over the age of 40 and suddenly find yourself holding objects at arm’s length in order to see them clearly, then you may be suffering from presbyopia, which inhibits the zoom function or accommodative power of the eye.
When the eye is relaxed and accommodation is at its peak, your eye can see any object in the distance quite clearly. On the other hand, when you need to see an object up close, the eye has to increase its accommodative power and effectively zoom in by altering the shape of the lens.
Everyone has a dominant and non-dominant eye and the brain is constantly processing visual information it receives from both eyes via the optic nerve.
However, the brain tends to rely on your dominant eye for the majority of your vision while the weaker, non-dominant eye acts more like a back-up option.
When it comes to treating presbyopia with more advanced technology, like the Presbia corneal inlay, monovision is induced by placing a clear microlens into the middle layer of the cornea of your non-dominant eye.
What’s more is that the Presbia inlay is a reversible procedure so that if your presbyopia gets worse and you need a higher prescription, a new microlens can be implanted in place of your existing one.
When it comes to distance vision, your pupil will dilate as normal and you use the surrounding corneal tissue not covered by the lens as well as the centre point of the lens that hold zero refractive power.
For near vision, your pupil gets smaller and the outer zone of the inlay that contains refractive power bends light correctly so that it focuses on the retina and images appear clear.
By producing a bifocal optical system, the brain learns to adapt to the Presbia microlens and within a few days you feel more comfortable and soon forget that you have the inlay.