Short-sightedness is a very common cause of reduced vision affecting 1 in 4 people in the UK where distant objects appear blurred and close objects are clearly visible. It usually develops from 6-13 years of age, typically worsening during teen years as the eyes grow and stabilise in early adulthood.
Often short sight is referred to by its medical term ‘myopia’. In everyday life this may mean that if you are short-sighted you will be able to read books clearly but will have problems watching television, driving or being able to visit the cinema and see the screen clearly. In the United States, this condition is referred to as near-sightedness.
If the world beyond your near vision seems foggy or blurred then it is likely you are suffering from short sight or ‘myopia’.
Short-sightedness is when light from a far object focuses at a point in front of the light-sensitive layer (retina), rather than directly on its surface (think of an arrow falling short of its target). This occurs when the eye has grown slightly too long and/or the overall focusing power of the eye is too strong. If you are short-sighted, the first number of your spectacle or contact lens prescription will be a negative number e.g. -2.00. A person has low short-sightedness if their prescription is -0.50 to -3.00, and high short-sightedness with -6.00 and higher.
Why does it happen?
Short-sightedness can run in families so you’re more likely to develop it if one or both of your parents are short-sighted. It has also been linked with doing excessive close work for long periods (e.g. reading) and a lack of time spent outdoors during the childhood development years.
Why do people develop it?
Long-sightedness can run in families so you’re more likely to develop it if one or both of your parents are long-sighted, or it can develop with age as the focusing ability of the eye reduces.
How does long-sightedness affect vision?
A short-sighted person struggles to see things far away (e.g. road signs, television screen, train signs), and have better vision in the closer range. The distance they can focus from their eyes depends on their level of short-sightedness – a person with -2.50 prescription can read at a distance of 40cm while someone with -10.00 can only see clearly 10cm from their eyes!
In some instances, an individual’s short-sightedness is very mild. They may choose to wear glasses only occasionally if they are visiting the cinema for example or wear contact lenses as and when needed. Therefore the minor inconvenience of having to put in contacts or find a pair of glasses when the occasion presents itself is something that some people choose to put up with.
An example of short sight – near objects are in focus whilst distance vision is blurred.
However, for others, the desire to see clearly at all times means they often wish to consider laser eye surgery or refractive lens exchange. Refractive eye surgery for short sight is a simple procedure that can often be life-changing. For those who have persisted with blurred vision, refractive surgery can instantly provide a ‘new world’ of clear vision and comfort.
How can it be corrected?
Short-sightedness can be treated by spectacles, contact lenses or refractive surgery (laser, lens implant or other). In recent years, there has been a lot of interest in finding ways to limit the development of short-sightedness in childhood including wearing contact lenses to re-shape the front of the eye (cornea) and wearing multifocal spectacles or lenses, where more than one prescription is built in. Research is ongoing in this area.
The term ‘myopia’ is often used to describe decisions or opinions that fail to consider anything beyond a narrow range or the present time. Anthony Marais famously wrote “From our myopia arose our dystopia”.