Myopia, or short-sightedness, occurs when the eye is too long for its focusing apparatus. In a normal eye, the cornea, then the lens, should focus light onto the retina, which converts the light image to electrical signals which get passed to the brain. Below, we discuss various methods of myopia control.
In myopia, light from far away is focused to a point in front of the retina, which results in blurred vision – only light from nearby objects are focused on the retina properly, and therefore appears sharp and in focus. The issue is myopia – particularly high myopia – can cause problems in the eye, later in life, even if the vision is corrected with spectacles, lenses or refractive surgery. One example is people with high myopia have a 5-6 times greater risk of retinal detachment than people with low myopia.
Need more info? The links on this page refer to ELZA pages (in English) with more detailed information on the topic.
Myopia is increasing massively. In 2010, 2 billion people were short-sighted. By 2050, according to the World Health Organization (WHO), 5 billion people will already be short-sighted, or 50% of the world’s population.
Nowadays, we spend much more time reading distance than our ancestors. Computers, but also smartphones and tablets cause our optics to be constantly focused at a distance of 20 to 60 cm. This constantly activates the process of so-called accommodation: we make an effort to focus in the vicinity. This stimulates our brain to make the eye short-sighted, because myopia means that you can see close up without any effort.
Another reason for the strong increase in myopia is probably also the artificial light that accompanies us over long stretches of our everyday life. The composition of the artificial light, in contrast to natural sunlight, does not release the messenger substance dopamine. And it is precisely the dopamine that can slow down a progression of myopia.
Contact lenses, spectacles, and in adults, refractive surgery, can change how the light is focused so it lands on the retina correctly. However, these people are still myopic; their vision has simply been corrected, but they still carry all of the risks associated with being myopic.
It’s important to understand that myopia is a disorder that forms during childhood. Myopia occurs if the eye grows too long to focus light from far away onto the retina. Childhood is therefore the only opportunity to influence the progression of myopia.
There are two types of childhood myopia, stable and progressive, and it is the latter we can influence, with either eyedrops or special contact lenses. As mentioned above, it is worth trying to slow the progression of myopia, not because of the requirement for thicker spectacles, but to try to improve your child’s depth of focus with spectacles, and to reduce the risks of developing myopia-caused retinal detachments in later life.
Highly diluted atropine solutions (0.01%) have been shown in a large study performed in adolescents in Asia to slow the development of myopia. The eyedrops are taken once a day in the evening, and the child needs to take the drops for a prolonged period – potentially several years.
Ortho-K lenses are worn at night and flatten the cornea in the center and the periphery. Multifocal contact lenses are worn during the day and contain various optical zones. The eye grows in length (becoming myopic) in response to how blurred peripheral vision is on the retina. These contact lenses attempt to address this by better focusing peripheral images onto the retina.
A new generation of eye glasses also is able to prevent myopia progression, working with mechanisms similar to the ones described above.
All three approaches slow myopia progression; the choice will depend on the individual circumstances of your child.
As ELZA is a world-leading refractive center, we have highly experienced doctors and optometrists with access to the most sophisticated instruments to examine your child’s eyes. These include ray-tracing technology to measure the total length of the eye, as well as corneal tomography and epithelial maps to fully understand if there are any other pathologies in the cornea that might cause myopia.