Understanding your eye prescription

If you’ve stumbled across this blog, that probably means you’re looking to better understand your eyesight and any issues you may currently be experiencing.

Well, first things first then, are you reading this up close with the text enlarged and face pressed to the screen? Or perhaps you’re holding the screen away from your face and squinting to focus on the letters?

Either of these methods are both very clear signs that you need glasses.

Often hereditary, short-sightedness and long-sightedness are common conditions which diminish a person's eyesight. Although easy to treat, people - especially young people - can often delay an appointment at their local opticians, but we can’t stress how important it is to get your eyes tested and find a solution to your eyesight problem. Some visual problems can lead to further eye problems for children including eye squints or lazy eye or result in later life eye conditions such as glaucoma, cataracts or retinal detachment.

We’ve explained a little more below about how to better understand your sight, including what does long sighted and short sighted mean, and ways to treat this.

Who’s that waving at me?

Constantly finding yourself squinting into the distance as your try and work out who that friendly looking blurred shape is?

If you’re nodding your head along as you recount the number of times you’ve waved back without a clue who that is by the traffic lights, or you’re cringing at the memory of not recognising your wife until she was at least a foot away from you – you might find that you are short-sighted and in need of some specs!

That is because short-sighted people (myopic) have difficulty seeing objects at a distance. Their vision is clear when looking at things up closely, but further away objects become out of focus or blurred.

This can be a real issue when out and about. Imagine the mild panic when your small child disappears out-of-focus as they set loose amongst the aisles during the weekly shop, or the sinking feeling when you lose sight of the ball, during the final minutes of a rugby match.

However, short-sightedness can be easily treated. The vision condition is in fact, the most common eyesight problem in the world, with many experts believing that by 2050, half the world’s population will be short-sighted. You’re not alone, so don’t continue to squint in silence!

Short-sightedness occurs when the distance from the front to the back of the cornea’s curve is too steep, or the eyes grow slightly too long. This forces the light to focus in front of the retina, making objects in the distance appear blurred.

To treat this, negatively powered lenses are required to improve distance vision. So that’ll be why you often hear of prescriptions that are -5.00 or similar. You may also notice that the lenses in your glasses might look ‘thinner’ at the middle and ‘thicker’ at the edges.

Essentially by adopting a minus prescription, you’re reducing the eyes’ focusing power to improve clarity for distance, and in turn avoiding running into anyone you don’t want because you didn’t recognise them from afar…

Patients with short-sightedness may also opt to use contact lenses depending on their lifestyle.

Whichever solution you opt for you may need to wear glasses or contact lenses all the time, or just when you need them for clear distance vision like when you’re driving or watching a film.

What’s that line say?

Is your partner fed up with reading the restaurant menu to you?

Well, give your extended arm a rest and get an eye test booked instead as it sounds like you’re probably long-sighted.

The opposite to short-sightedness, long-sightedness (hyperopia) allows people to see objects clearly at a distance but find it hard to focus on things close to them. That means that everyday tasks like reading the paper or trying to work off a computer screen can be more difficult, and result in eye strain and blurred vision. This in turn can lead to further fatigue and headaches.

It’s often found that children and young adults with long-sightedness don’t need any treatment, as their eyes are often able to adapt to the problem with the help of the muscles in their eye, and their vision may not be significantly affected. However, treatment is usually required in older adults, particularly those over 40, as your eyes become less able to adapt as you get older.

Long-sightedness occurs when the light coming into the eye isn’t able to focus properly at the back of the eye. This can be caused by the eyeball being too short, the cornea being too flat or the lens inside the eye being unable to focus properly.

But just as with short-sightedness, this common complaint can be easily treated with either glasses or contact lenses.

Sufferers will be prescribed glasses that have a prescription that contains plus lens power, e.g. +2.50D with lenses that are made specifically for you, which ensure light is focused onto the back of your eyes correctly. As long-sightedness can increase with age, the strength or the prescription of your glasses may need to be increased as you get older.

In much the same way your vision is the opposite to that of short-sighted people, you may also notice that the lenses in your glasses are also the opposite, looking ‘thicker’ in the middle and ‘thinner’ on the edges.

Similarly, long-sighted sufferers usually wear contact lenses which are ‘plus’ or convex in shape to achieve normal vision.

A 20 20 outlook

Prescriptions are designed to get you as close to ‘perfect’ vision as possible. But throughout your life, it’s likely that your prescription will change over time. There’s nothing to worry about, and most likely, you’ll just need to alter the strength of your lenses.

The rate of change in your prescription usually depends on your age. Short-sightedness often develops in childhood, while presbyopia (age-related loss of near-focus) affects everyone around the age of 45, while general changes in eyesight will often plateau and stabilise around 60.

Changes in your eyesight may also result in reading glasses or varifocals. Varifocals are incredibly clever lenses that allow you to focus on near objects and into the distance, while reading glasses, add a magnifying lens or ‘plus eye power’ as a solution for age-related loss.

All these changes can be picked up by your optician during regular eye tests, where the health of your eye can also be examined.

If you are concerned about changes in your prescription, all our branches across Scotland are now open and operating as usual.

All our branches across Scotland are now open and operating as usual. For more information on what to expect at an eye appointment, click here.