Myopia Control and Prevention

Myopia, also known as nearsightedness, occurs when the eyeball is longer than normal or when the cornea is steeper than average. Nearsightedness causes light to focus in front of the retina instead of directly on its surface.

Someone with nearsightedness may squint noticeably when trying to view objects in the distance. They may also sit very close to the television or bring books very close to their eyes when reading. Myopia requires visual correction, usually in the form of eyeglasses or contact lenses. Refractive surgery, such as LASIK, can also correct nearsightedness.

Myopia is receiving much more attention lately because the prevalence appears to be increasing significantly. Some countries view nearsightedness as either an epidemic or a public health crisis. In the United States, the prevalence of myopia increased from about 25% in 1971 to more than 40% by 2004. In some regions of the world, such as urb

an areas in China, the prevalence of myopia may be as much as 80% of the population.

Dangers of Myopia

Myopia has become a hot topic because of the possible risks associated with it. The severity of myopia is expressed in diopters, a unit used to describe the focusing power of a lens to correct vision.

Research findings vary, but a 2021 study estimates that each additional diopter of myopia increases the risk of:

• open-angle glaucoma by 20%
• cataract by 21%
• retinal detachment by 30%
• myopic maculopathy by 58%

Causes of Myopia

No one knows for sure what causes myopia. Genetics appears to play a big role. For instance, a 2020 study found that if one parent is nearsighted, the child has a 42% higher risk of becoming nearsighted by the age of 6. If both parents are nearsighted, that risk is more than 270%.

Historically, there has been a long history of an association of the increase in nearsightedness in people who are actively involved in doing more near work. Even as far back as the 1800s, scientists showed a relationship that people that had higher education or worked in an occupation that included a lot of near work, were much more nearsighted than those that did not have higher education or worked outside.

However, what is still not clear is the fact that personalities that are drawn to higher intellectual occupation or ones that involve much more near work (activities that involve a short working distance) may be made up of people who are drawn to those types of jobs or scholarly studies. This area is currently being investigated by many researchers.

Most of us are exposed to an inordinate amount of near stimuli with smartphones, tablets, computers and a host of other digital devices. The jury is still out on whether this is really something we as a society need to be concerned about or not.

There are just as many studies that show that near work does not cause nearsightedness as there are studies that show that it does. It is probably a more complex algorithm that includes genetics and the amount of time spent outdoors.

Environment seems to also play a role. There is evidence that shows that time spent outdoors seems to have a protective effect. Children who spend more time outdoors are much less likely to be nearsighted. Researchers are not exactly sure why, although it is thought to have something to do with exposure to daylight or perhaps being in a larger distance-oriented environment.

Can We Prevent Myopia?

Scientists and doctors promote the idea that if the progression of myopia can be cut to approximately 50%, the incidence of serious complications can be cut by a significant amount. Obviously, it would be even better if we could reduce any progression at all, but the current methods to reduce the progression of myopia have limited efficacy. Following is a list of possible ways to prevent or control myopia.

Visual correction

Many parents are concerned that if a doctor prescribes glasses to be worn most of the time, their child will become dependent on them or that the glasses themselves will cause more nearsightedness to occur. Some parents may feel that it is best to not correct the condition at all.

However, research shows that not correcting a child’s nearsightedness could actually cause the nearsightedness to worsen. In addition, under-correcting nearsightedness was once thought to have an impact on reducing the progression. However, current thought is that under-correction is associated with a higher rate of myopia progression.

Outdoor activities

Important studies have shown that time spent outdoors can delay the onset or even reduce the progression of nearsightedness. More research needs to be performed but the amount of time spent outside appears to at least be an important risk factor.

The reason why this is true may be related to a reduction in obesity, an increase in vitamin D production, socialized games that occur outside or may even be related to dopamine levels in the body. One of the strongest mechanisms of action currently being studied is the amount of sun exposure or the amount of illumination or simply brightness that you receive while outside.

Low Dose Atropine

Atropine ophthalmic solution has been shown to be quite effective in reducing the progression of myopia but not in slowing the rate of an increase in the length of the eyeball. However, many studies have shown a high rate of success at various concentrations (from 0.01% to 1%).

Atropine is given in eye drop form daily, usually at bedtime. The exact mechanism is not known. Studies have shown low dose atropine to be safe, though at high concentrations atropine can cause some undesirable side effects, such as sensitivity to light (photophobia).

Orthokeratology

Orthokeratology, also known as corneal refractive therapy (CRT) or corneal reshaping, involves wearing special contact lenses at night. They flatten the center of the cornea but steepen it at the edges, causing a change in the shape of the cornea that redirects incoming peripheral light in front of the retina (peripheral myopic defocus) rather than behind the retina (peripheral hyperopic defocus). This appears to slow the elongation of the eyeball, which slows the progression of myopia.

Even though the lenses are only used at night, their effect continues throughout the following day.

Multifocal Soft Contact Lenses

Children wearing soft multifocal lenses had 25% less myopia progression and 31% less axial elongation than those wearing single-vision lenses over two years, according to a 2014 study in Hong Kong children. Doctors believe it works by the same mechanism as orthokeratology.

The “center-distance” multifocals focus light in front of the peripheral retina, and they focus light right on the central retina, which provides people with clear vision.

A Word From Verywell

Preliminary projections based on real population data indicate that myopia will affect over 50% of the world’s population by 2050. Ten percent will have high myopia, which greatly increases one’s risk for glaucoma, cataracts, retinal detachment, and myopic maculopathy. Myopia is a real public health concern. Research shows that myopia control can decrease the progression of nearsightedness by 50%. As a result, it is worthwhile for parents to begin learning about the different options currently available.