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Print this definitionPresbyopia (age related near vision loss)

Presbyopia develops during middle age causing vision to blur at near. The effects of presbyopia are usually felt around 44 years of age, but that will vary depending on whether there are other pre existing eye conditions and what visual demands the eyes are normally under each day.

Although the onset of presbyopia is relatively slow, once the effects are noticed it can seem as if the condition has suddenly developed and this occasionally creates anxiety. What has actually happened is the protein fibres in the lenses of the eyes have changed over time, making them harder and less elastic, such that the lens cannot as readily change shape when required to alter focus between varying distances. This change reduces the amount of near focussing that was once achievable. Everyone will eventually experience presbyopia.

The most common way presbyopia is corrected is by wearing glasses.

As modern visual demands such as using a computer require more than one focusing point in a pair of glasses, single vision lenses are no longer the best option for correcting presbyopia. Extended focus lenses, which provide a full reading prescription in the bottom half of the lenses and a weakened prescription at the top (for viewing a monitor), provide a preferred solution.

Another option for people with presbyopia is to use progressive addition lenses (PALs), otherwise known as Multifocals. They provide distance, intermediate and near vision in one set of lenses. PALs may be the perfect solution for someone that requires a distance prescription also, or for people with good distance vision but have a constant requirement for clear distant and near vision throughout their working day.

PALs may not be the most appropriate option for someone using a computer for extended periods of time; this is because, in a workplace monitors often sit too high for viewing comfortably through the intermediate or near sections of the progressive addition lens. In this situation the only way to achieve clear vision for all situations would be to have two pairs of glasses; one fitted with PALs for general use and another with extended focus lenses which could be left by the computer.

Contact lenses may also provide a solution for someone with presbyopia. Although there are contact lenses available for correcting Presbyopia, there is a trade off in clarity of vision when using them. Another option is using contact lenses to correct distance vision in one eye and near vision in the other (mono vision).

Correcting the effects of presbyopia through refractive eye surgery is also possible, however the outcome and options are similar to those presented with contact lenses. For this reason, surgery is rarely prescribed as a typical option for people with presbyopia.

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