EYESIGHT – MYOPIA; PRESBYOPIA; ASTIGMATISM
In myopia, or short-sightedness, the person cannot see well at a distance, but his near-vision is usually good.
Simple myopia does not give rise to headaches.
Presbyopia results from the weakening of the ability to focus the lens.
This starts in the earliest years, but usually doesn’t give rise to any symptoms until the forties.
Then it tends to get worse as the person continues to age.
In presbyopia, increasing the amount of light available may make it easier to see.
Or he can have bifocal glasses which have an upper part for distance and a lower part for near-vision.
In astigmatism the cornea has irregularities and does not form a smooth rounded part of a sphere.
It is common in mild degrees but usually does not give rise to trouble.
In more severe cases, it is likely to interfere with distant and near-vision.
Astigmatism is usually easily corrected by the wearing of glasses.
*344/71/1*
