Myopia is the most common visual disorder in the world and strikes from childhood. These constantly increasing figures can be explained in particular by the explosion in the time spent on our screens to the detriment of outdoor activities. In this article, experts from JLR eye hospital will explain everything about myopia-
Towards a myopia pandemic?
Myopia is the most common visual defect in the world and the frequency of which has been increasing for several years. Scientific studies predict that the number of myopic people should double between the years 2000 and 2050 and affect nearly 5 billion people, or 50% of the world population.
As a reminder, myopia is a visual refraction disorder which results in blurred vision from afar and clear vision up close. Myopia does not prevent presbyopia, so you can be nearsighted and presbyopia (people take off their glasses to see up close). Myopia is most often due to an eye that is too long (anteroposterior axis> 24mm), we then speak of axile myopia.
Myopia most often starts in childhood, generally detected when entering school. It is between the ages of 7 and 12 that myopia progresses the most.
The child then complains of the symptoms of this disorder:
- blurred vision from afar;
- squinting of the eyes;
- bringing books or screens closer to the face;
- untimely blinking and rubbing;
- headache ;
- eye fatigue.
Who is most at risk of becoming myopic?
The myopia epidemic is explained both by genetic factors but also by the evolution of our way of life. If one in two people will be nearsighted in 2050, it is because today some children develop this disorder for two major reasons:
- genetic predispositions : a child who has a myopic parent is twice as likely to become myopic. He is six times more likely to be if both his parents are nearsighted;
- lifestyle: children who carry out a lot of activities with near vision and artificial light (reading, work or activity on a screen) are exposed; children who stay indoors to the detriment of outdoor activities (exposed to natural light) are also at risk.
What are the solutions to slow down myopia?
Spend time outdoors
Studies have shown that spending time outdoors, exposing yourself to natural light every day, is a protective factor against the development of myopia. In addition, children who practice little outdoor activities are on average more myopic than those who practice them regularly and for a long time.
Corrective lenses
Classically, myopia is corrected by single vision and concave lenses. The corrective lens for myopia is thicker at the edge than at the center. However, with conventional single vision lenses, if the central image is well positioned on the retina, in the peripheral zone, the image is located behind the retina. The eye will then lengthen to compensate for the induced blur. This is why new generations of lenses with specific geometry provide myopic defocusing. This makes it possible to bring the peripheral images in front of the retina and to slow down the lengthening of the eye. These lenses reduce the progression of myopia and ensure clear vision.
Several other treatments are possible on the myopia correction lens. Most of the existing lenses are anti UV at 380nm thanks to their material and benefit from an anti-reflection treatment (which offers better transparency of the glasses), anti-scratch or even anti-blue light. To wear the same frame indoors but also in the event of sunshine, the myopia correcting lens can also be photochromic. A photochromic lens is a corrective lens capable of tinting depending on the amount of ultraviolet to which it is exposed.
For children, it may be advisable to wear impact resistant glasses. This is the case with organic lenses, which are compatible with all corrections and all treatments.
The optician can provide good advice in order to select the correct frame: it is adapted to the morphology of the face but also to the personality and lifestyle of the patient.
Contact lenses
Very thin and concave, they are put on the eye to correct vision defects. They are suitable in case of myopia. They are worn all day and can be taken off at bedtime. Some new generation soft lenses not only provide optical correction but also a treatment that creates myopic defocus. This type of lens can slow down both the progression of myopia and the elongation of the eye.
It is possible to equip children and even infants with contact lenses. Indeed, these have the advantage of ensuring the development of the child in the case of strong corrections, without the need for thick glass. In addition, the advantage of being a child is that lenses do not break or get lost, unlike glasses.
Conclusion
With the ever-increasing global prevalence of myopia and high myopia, it is crucial to control the onset and progression of childhood myopia. The control of myopia can therefore be obtained by slowing its onset, which now seems possible by increasing the time spent outdoors, and by slowing its progression, thanks to treatments such as low-dose atropine and orthokeratology. To date, treatment with low-dose atropine has demonstrated the most convincing efficacy in randomized, double-blind studies. There are also corrective lenses comprising a defocusing system and defocusing contact lenses which have demonstrated some effectiveness in curbing myopia and which could be combined with other treatments.
