Definition: what is myopia?
Myopia is when objects that are far away appear blurry and those that are close up are clear. People with myopia don’t need glasses to read but will need them in everyday life such as for driving a car. The stronger the myopia is, the further the person will need to hold their book away from their eyes in order to see it clearly.
Myopia is often due to an eye that is long distanced. Vision is a little like a video camera, in the way that images have to be developed by the cornea and the lenses and projected onto the retina in order to be correctly transmitted to the brain. For someone with myopia, when the object is far away, the focus of the object’s image is formed in front of the retina.
In Europe, it is estimated that around 30% of the population are affected by myopia. Myopia isn’t considered an illness, but a visual disturbance.
Myopia: what are the symptoms and how does it progress
The first signs of myopia are quite easy to spot, especially in adults. Whilst driving a car, the person will find it difficult to distinguish between traffic signals or will see them at the last minute and will find it difficult to recognise people that they meet in the street. One of the most common signs is squinting your eyes in order to see far away properly.
In children, myopia can be spotted when children bring their books closer to their eyes to read or when they move closer to the television. Sometimes it is their teachers that notice these first signs and inform the parents.
Myopia generally begins to show itself around the age of 6 and develops until the age of 25 when it then stabilises. Myopia that starts really early will be more significant than that which starts later. Myopia can also appear later on, even after the age of 20 and can also develop progressively until the age of 60.
Myopia: what are the causes?
In the majority of cases, myopia is genetic. A child is more at risk of being affected if one of their parents is also affected. It is not uncommon to find many people with myopia in the same family. Many genes have been identified by researchers, but the transmission of myopia isn’t very well known.
However, environmental factors seem to be responsible for many years for the rise in the cases of myopia. Outdoor activities in natural light have decreased in favour of indoor activities and time spent in front of the television, video games or computers. Several studies have recently brought to light that the more people are exposed to natural light, the less they are likely to be affected by myopia.
Studies have also shown that myopia increases in countries that are industrialised, with a socio-economic level and a long duration of studies. Reading and detailed work at school is very straining on the eyes and contributes to myopia.
Myopia: how to correct it
Myopia is corrected with glasses or contact lenses. They are used to lower the sharp-focus on the retina and to reestablish a good long distance.
Myopia can also be corrected by surgery, a method which is more and more common nowadays. This surgical correction of myopia can be subtractive or additive. The subtractive method, which is done with a laser, aims to modify the curvature of the cornea, whereas the additive method aims to add an implant to the inside of the eye.