Contact Lenses for Presbyopia

Multifocal soft contact lenses are a fairly recent development and have been designed to solve a very difficult conundrum. Unlike glasses multifocal lenses it is not possible look towards the bottom of the lens for increased reading vision due to the tracking effect of the lens, the lens will follow your eye wherever it is.

As such the design philosophy is completely different. Each lens brand is designed slightly differently, however, the majority use a concentric ring pattern to correct the varying focal distances required (see opposite).

Concentric ring patterns alternate distance and near focus and in this specific design, shown opposite, the dominant eye wears a "centre distance" lens and the non-dominant eye wears a "centre near" lens. This means that both eyes receive some near vision and some distance vision but one eye is biased to one or the other focus giving a form of modified monovision. (see below for details of monovision).

This system works very well the majority of the time, however, there are some points to bear in mind. Due to the concentric ring pattern some glare can be seen initially, however this should be easily overcome with continued wear. The vision will never be as good as with spectacles. It is important to understand that there is a compromise to be made with these lenses. While they will allow you to view most things most of the time you still may struggle with intricate tasks. Reading spectacles may still be required for sustained reading of for reading very small print in poor light.

How to determine your dominant eye.
Make a small triangular shape by overlapping your hands in front of you and outstretch your arms so that the shape made is in front of your face at arms length. Focus through the shape at a target in the distance and slowly bring your  hands towards hour head until they touch your face, all the time keeping the target in view through the shape. You will find that your will automatically draw your hands towards your dominant eye covering the non-dominant one.

Monovison

Monovision is the system of using a distance singe vision contact lens in your dominant eye and a single vision reading lens in your non-dominant eye. This will give relatively good distance and reading vision but won't necessarily be perfect for intermediate, computer screen vision. Because only one eye is used for each task it is worth noting that the vision is slightly reduced when compared to spectacle wear, it also can take a short while to become accustomed to this unique type of wear. However, in the majority of cases it works really well.