Healthy vision

Deteriorating eyesight? It's only natural

Research shows that most people over the age of 40 wear spectacles all or part of the time. Vision, like hearing, is something most of us have from birth and take for granted. Yet eyesight can begin to deteriorate at any time of life, which is why it is important to have regular eye examinations with a qualified optician.

The age when people first notice this deterioration varies enormously, but it happens to everyone sooner or later. Perhaps it gradually becomes more difficult to read small print in poor light. Or you find that you have to hold newspapers or telephone directories further away from your eyes in order to focus properly on the words.

This is because as we get older, the lens of the eye thickens and slowly loses its flexibility, leading to a gradual decline in our ability to focus on close objects. This is called presbyopia. It is not a disease but a normal and expected change which sooner or later affects everyone, even people who have previously had perfect eyesight.

What is presbyopia?

Presbyopia is a natural condition that affects the flexible crystalline lens within the eye, causing it to lose its flexibility and become more rigid. This makes it less able to focus clearly at all distances.

The lens also becomes thicker, altering its focal length. People usually start to notice the effects of presbyopia during their 40s. As soon as you begin to notice these changes you should visit an optician for a full eye examination.

The eye examination

Your optician will carry out a series of painless tests on your eyes using special equipment to measure the accuracy of your vision.

They will also shine a light in through your pupils using an instrument called an ophthalmoscope, which allows them to examine closely the inside of your eye without causing you unnecessary discomfort. This procedure is important because it enables the optometrist to check the health of your eyes and helps to detect several conditions which affect the blood pressure.

Another condition which could be detected is glaucoma.

What is glaucoma?

Glaucoma is a condition in which the optic nerve is damaged, often due to increased fluid pressure within the eye, making it feel harder. If untreated, the area you can see becomes smaller and smaller (commonly known as tunnel vision), eventually leading to severely impaired vision and even blindness.

But, if discovered and treated early enough, the condition can be slowed or halted altogether, resulting in satisfactory vision that is retained for life. A test is routinely carried out for glaucoma in people aged over 40, using an instrument called a tonometer. The optometrist is also likely to use a non-contact tonometer to blow a puff of air at the eye to measure internal pressure. Some people are more at risk of developing glaucoma than others, including people who are diabetic or anaemic, or have hardening of the arteries.

It is almost impossible for anyone to know that they have glaucoma without being tested because deterioration is very gradual. The eye also has the ability to adjust to some degree of raised eye pressure so you will not notice any immediate changes in your vision. The only way to be sure is to have regular check-ups, preferably every two years, or more frequently if your optician believes you may be at risk.

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