5 ways to control Myopia
Myopia, commonly referred to as short-sightedness or near-sightedness, is a refractive error that is increasing in prevalence. Here a person can’t see distant objects clearly. Myopia is a very common problem that can be corrected and even managed.
Affecting 21.15% of school-going children (aged between 5-15 years) in urban India, myopia (short-sightedness) is a condition of concern as compared to hypermetropia (long-sightedness). In fact, WHO has estimated that by 2050, half of the world’s population would be myopic, if not addressed appropriately.
Certain studies conducted post-pandemic have reported a sudden surge in the cases of myopia in children globally, due to home confinements which lead to increased screen time. Usually, the onset of myopia is in childhood when the eyeball lengthens excessively, resulting in blurry vision for far. Additionally, because children’s eyes continue their axial elongation as they age, the minus number tends to keep increasing if no intervention is made. This can significantly affect a child’s daily life and occasionally cause long-term eye health issues like retinal detachment.
Can myopia be cured?
– Myopia occurs when the eyeball is longer than normal
– The eyeball cannot shorten in length.
– Thus, Myopia cannot be cured. But it can be treated and controlled. Treatment is by wearing glasses of the correct prescription. Control is adopting strategies mentioned below to reduce the risk of progression.
Fortunately, fresh research is illuminating the way to better methods for managing myopia. How? Read on:
5 Myopia Management Methods
1. Environmental factors and Lifestyle Modifications
Myopia progression has been linked with an increased amount of screen time or near work. This is why we have seen a sudden surge in the progression of myopia post-pandemic. The more the near work the greater the chance of myopic progression in children. Near work thus is the most significant risk factor for myopic progression. Thus reducing screen time would result in slowing of myopia progression. Furthermore, the American Academy of Ophthalmology has recommended the amount of screen time for each age group of children
Additionally, research has shown that a certain level of UV exposure in natural light is necessary to reduce the risk of myopia progression. Thus, it is recommended that parents increase the outdoor time their children spend. Outdoor activities also allow us to look far away more than our time indoors. , which is said to reduce the rate of myopia progression. The following graph summarises the three most important lifestyle modifications needed to control myopia.
2. Special types of Myopia control Spectacle lenses
Lenses for myopia control can correct and control myopia. Given that wearing glasses is probably easier, this is a good option for myopia management to begin with. Spectacle lenses with DIMS and H.A.L.T. technology go beyond conventional spectacle lenses to control myopia. Imagine DIMS (Defocus Incorporated Multiple Segments) and H.A.L.T. (Highly Aspherical Lenslet Target) technologies as myopia-correcting single-vision lenses with an additional “treatment zone” on top of the regular lenses.
How do spectacle lenses with the DIMS and H.A.L.T. technologies function?
Based on available studies, we describe, how they help in slowing myopia progression.
Following are the features of DIMS and H.A.L.T spectacle lenses (Figure 1):
– Each lens has a distinct central zone like the regular single-vision lens and a “background” of single-vision correction lenses which is different from the regular single-vision lenses.
– This peripheral zone has a number of lenslets within it to produce varying degrees of myopia across the retina, and there are spaces between them for a single vision correction. Producing varying degrees of myopia means the rays of light start meeting in front of the retina because of these lenslets and not behind them as it happens in single-vision lenses. This is also known as Myopic Defocus.
– As opposed to a progressive addition or bifocal spectacle lens, each function like a single-vision lens in that it does not affect accommodation or binocular vision.
Two-year randomised clinical research was conducted by Hong Kong Polytechnic on children aged 8 to 13 with myopia of -1.00 to -5.00D and no more than 1.50D astigmatism. They made half of the children wear DIMS design and the other half wear single vision (SV) lenses. After two years, the average increase of myopia in children in DIMS and SV, respectively, was -0.41D vs. -0.85D and 0.21mm vs. 0.55mm, indicating a 50–60% control effect. The paper reported that 21.5% of children who wore DIMS had no myopia progression over two years, compared to only 7% of those who wore SV lenses.
Thus they showed that these myopia-correcting lenses slow down myopic progression.
3. Low Dose atropine eye drops for myopia (0.01%)
Atropine is used for controlling myopia progression for a few decades, however, there wasn’t a long-term study available as concrete evidence. But recently a study known as ATOM (Atropine in the Treatment of Myopia) had done a 2-year-long assessment of myopia progression where they had given a set of myopic children low-concentration atropine 0.01% and a set of myopic children nothing and found that children who were given 0.01% atropine had reduced rate of myopia progression as compared to the normal no intervention group. With the lockdown imposed during the COVID-19 pandemic, there was suddenly a surge in myopia and interestingly even 0.01% atropine was found to be less effective. Thus, atropine 0.05% was then compared with 0.01% atropine to compare the efficacy and also the side effects which showed that 0.05% atropine slows myopic progression with better efficacy with minimal side effects in the children. Thus, along with 0.01% atropine, gradually 0.05% atropine is also getting into clinical practice to reduce progression in children. It’s important not to use regular atropine eye drops which are 1% in concentration.
4. Contact Lenses for Myopia
Multifocal Contact Lenses: Multifocal soft contact lenses can correct myopia in youngsters while also halting the progression of myopia by delaying pathological eye growth. They are primarily used to improve near vision in persons over the age of 40. The soft multifocal contact lenses are shaped like a bullseye and have two basic light-focusing regions. For clear distance vision, the centre of the lens corrects near-sightedness and directs light onto the retina. To focus the stray light rays in front of the retina, more plus power is added to the lens’ outer section. According to studies, focusing light in front of the retina signals the eye to restrict its growth. Peripheral light is focused farther in front of the retina with higher additional power or in other words a myopic defocus. Contrarily, regular contact lenses and single-vision glasses concentrate peripheral light at a location behind the retina, which causes the eye to continue developing. The researchers looked at whether high-add-power contact lenses slowed myopia development and eye growth more effectively than medium-add-power lenses. They discovered that the only contact lenses that significantly slowed eye growth were those with a high addition power.
5. Orthokeratology Contact Lenses:
Orthokeratology is the process of designing stiff gas-permeable contact lenses specifically to temporarily reduce or eliminate the refractive error by reshaping the corneal curvature. It is based on the idea of reverse geometry. OrthoK lenses press against the central corneal surface, reshaping the cornea. This flattens the cornea, i.e., the front part of the eye which decreases the eye’s axial length and focusing power. According to research, corneal reshaping, the lenses create a plus-powered ring in the periphery because of increased cell count and thus creating the plus-powered defocus like soft multifocal contact lenses and DIMS spectacles. OrthoK lenses are supposed to be worn by the child at night before sleeping and get a good night’s sleep with the lenses on. Best results are found in patients having myopia up to -5.00 dioptres. For refractive errors beyond -5.00, a customized OrthoK lens has to be designed. A major concern as a parent is about infections, thus Prof. Mark Bullimore had done a study to investigate the risk of infection in children due to overnight OrthoK lens wear and found the risk to be less than 1%, provided the care and maintenance regime of the lenses are followed appropriately as prescribed.
Summary
– Effective myopia control is important for us parents to think about.
– Increased near work is a risk factor for axial myopia progression.
– The following are the interventions for myopia control
– Reduce near-work or screen time
– Increase outdoor playtime
– Start using low does atropine
– Can consider using myopia-control spectacles
– Alternative to spectacles is multifocal soft contact lenses or orthokeratology.
Pro Tip – These myopia control spectacle lenses are usually not available at optical shops. Please speak to your eye care provider and confirm if they can fit these lenses for you.