Presbyopia

This is a condition of vision in which the individual has difficulties in focusing on near objects and in reading fine print. The condition is commonly seen after the middle forties due to the diminished power of accommodation from impaired elasticity of the crystalline lens. 

The signs of presbyopia include blurred vision at the reading distance and a need to hold reading material further away. Other symptoms include headache, fatigue, or difficulty concentrating when doing close work. Extra plus power is needed to correct presbyopia. 

 This can be in the form of reading glasses, or bifocals, or progressive lenses. Early myopic presbyopes can be slightly undercorrected at distance to give them some more time before they need a full reading correction. As the focusing ability of the eyes is reduced gradually over time, the near correction must be made stronger periodically. 

 The already hyperopic patient will have earlier trouble with near vision as he becomes presbyopic. If you have just the right amount of nearsightedness, you may be able to simply take off your regular glasses to read. It is like having built-in reading glasses. 

Mono-vision is recommended by many LASIK surgeons for their patients aged 35 years and above who are presbyopic, or who are likely to become so in the near future. The aim of mono-vision correction is to enable the patient to have a close to full range of vision with much reduced dependence on glasses for both distance and near vision. This is achieved by aiming at full or close to full correction in the dominant eye and mild under-correction in the other, non-dominant eye.