Stephen J Manton B.Sc.(Hons.), F.C.Optom.

PRESBYOPIA - THE OVER 40's EYESIGHT PROBLEM

When you are young, the tiny lenses inside your eyes are wonderfully flexible. If a youngster holds a wrist watch even six inches from his nose, he will be able to see the time at a glance. However, when one becomes middle-aged, the lenses in ones eyes begin to harden (this is the start of presbyopia), which means that if one holds ones watch nearer than a foot or so to ones eyes then it is difficult to tell the time by it. As the years go by this hardening progresses until it becomes impossible to tell the time at all even when holding the wrist watch at full arms length.

What is the solution to this problem?

There are several solutions, as follows:-

READING SPECTACLES  

Whenever you wish to see anything clearly within arms range, you will have to put on your reading spectacles. However, when you look up through them, all is not clear. The television is blurred and you certainly cannot walk about with them on. The result is that you will have to keep putting them on and off. This can be solved by wearing half-spectacles or bifocals.

BIFOCALS  

If you require both a distance and a near prescription then bifocals are an alternative to having two pairs. These lenses have a top part for distance seeing and a bottom segment for reading. They are available in many styles and sizes, the best type for you will be discussed following your eye examination. As your presbyopia increases you may find that at certain distances, for example shopping or reading music, your vision is not clear through the top or the bottom part of the bifocal. This can be remedied by wearing trifocals or varifocals.

TRIFOCALS   

These lenses have three parts, distance, intermediate, and near, thus solving the problem. This is important in the office where one has to read small print within arms length, read beyond arms length on a desk and also see clearly at a distance. However, with bifocals and trifocals there are dividing lines between the different parts of the prescription. Some people find these lines annoying and more especially many people find them unattractive to wear - which brings me on to varifocal lenses.

VARIFOCALS  

These lenses have no dividing lines at all. The power gradually changes from distance sight at the top through the intermediate stages to the near vision at the lower part of the lens. They may take a little while to get used to, but are considered specially by women to be much better looking than bifocals or trifocals.