Eye tests for ageing drivers will do far more than make roads safer

• Drivers over 70 who fail eye tests face ban in road safety overhaul

Estimates vary as to just how many drivers can’t see well enough to meet the legal requirements, but a recent roadside survey carried out by police forces across England, Scotland and Wales involving the testing of 900 motorists found that 1 in 45 of them failed the number plate test, suggesting there are close to one million people on our roads who cannot see well enough to drive safely. And, because eye health deteriorates with age, most of them will be older people (the average age of those who failed in the survey was 69).

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The sort of gradual loss that occurs in some eye conditions, such as glaucoma or cataracts, can be surprisingly easy to miss, and failing the test would have come as a surprise to some. However, I suspect others would have known that their vision was marginal, not least those who required glasses or contact lenses to reach the DVLA standard, but were driving without them. Not wearing your specs when you need them to drive is little different to jumping behind the wheel after drinking too much alcohol and, in my opinion, should be treated just as harshly.

However, it’s not all about road safety. Regular eye tests not only help you optimise your vision for everyday life but they can also detect worrying health problems before they would otherwise come to light. Some of these are rare, like the patient of mine whose optometrist spotted an early melanoma on her retina, but others are really quite common and can be broadly divided into eye conditions that can lead to visual loss, and changes that reflect problems elsewhere in your body.

Eye problems that can have an insidious onset and are often only picked up in routine eye checks include early cataracts (clouding of the lenses), macular degeneration (retinal damage that can lead to loss of central vision) and, perhaps most worrying of all for drivers, glaucoma, as it is common, easily missed and can lead to irreversible visual loss. It is a leading cause of blindness in the UK.

The term glaucoma embraces a number of conditions that are typically associated with raised pressure within the eyeball and damage to the delicate optic nerve that takes signals from the retina to the brain. According to the National Institute for Health and Care Excellence, as many as 1 in 20 people over 40 in the UK will have abnormally high pressure in their eyes, normally only detectable by measurements during an eye test. Most won’t go on to develop glaucoma, but in those that do, the earlier treatment (like pressure-lowering eye drops) is started, the greater the chance of preserving vision.

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The back of the eye allows direct visualisation of both nerves and tiny blood vessels, and changes in the appearance of either can give clues to more distant problems including high blood pressure, abnormal cholesterol levels, diabetes (type 1 and 2) and even brain tumours.

So regular eye checks — for everyone, not just older drivers — could improve road safety, help to prevent and treat some common types of visual loss, and pick up silent threats to your health. And they are often free. Eligibility varies slightly depending on where you live, but as a rough guide adults should be eligible for a free check if over 60 (40 if you have a close relative with glaucoma) or you have existing visual impairment (registered partially sighted or blind), diabetes or glaucoma. Two-yearly tests are free for all adults in Scotland.

I had my last check a few months ago and all was fine. However, while my long-range vision is good, my near vision is getting worse. Or to put it another way, the road ahead of me may be crystal clear, but my dash is starting to become blurred. And if I were to use my readers to get a clear view of the dash, the road ahead would be fuzzy. All easily fixed with varifocals, albeit not free of charge …

DVLA standards of vision for a normal UK driving licence

• You must be able to read (with glasses or contact lenses, if necessary) a current standard car number plate from 20m.
• You must meet the minimum eyesight standard for driving by having a visual acuity of at least 6/12 — that is being able to read the 5th line down on a standard Snellen eye chart test (normal vision 6/6 or “20/20” would be the 7th line down) — again, with glasses or contact lenses if necessary, using both eyes together or, if you have sight in one eye only, in that eye.
• You must also have an adequate field of vision — your optometrist can tell you more about this and do a test.