As an eye specialist in Japan, I often encounter children at risk of developing high myopia, a condition that significantly impairs vision. I diligently advise parents on methods to curb the progression of myopia in their children. Unfortunately, I frequently observe a lack of awareness among parents about the control of myopia and its potential risks to their child’s eye health.
What is high myopia
The degree of myopia is classified as follows:
- Mild Myopia: Less than -3.00 diopters
- Moderate Myopia: -3.00 to -6.00 diopters
- Severe Myopia: -6.00 to -9.00 diopters
- Extreme Myopia: More than -9.00 diopters
High myopia typically encompasses both severe and extreme myopia. This classification highlights the increasing severity and potential impact on vision and overall eye health.
Risks of High Myopia
High myopia is problematic for two main reasons. Firstly, it significantly impacts daily life – for example, individuals with high myopia often struggle to locate their glasses. They require thick lenses, leading to discomforts such as heavy glasses, distorted peripheral vision, and appearance changes. These issues often drive individuals towards excessive contact lens use, which can cause corneal problems.
Secondly, high myopia increases the risk of serious eye diseases like glaucoma, retinal detachment, myopic traction maculopathy, choroidal neovascularization, and macular atrophy.* These conditions can lead to vision loss and often manifest at a younger age in highly myopic individuals, profoundly affecting their quality of life.
The other reason is that individuals with high myopia are at a greater risk of developing vision threatening diseases, such as glaucoma, retinal detachment, myopic traction maculopathy, choroidal neovascularization, and macular degeneration*. They also sometimes develop cataract in younger age. I think progression to high myopia during adolescence influence life.
The Myopia boom in EAST Asia
Myopia is on the rise globally, especially in East Asia. About 30% of the world’s population is now myopic. In East Asia, the increase has reached epidemic levels – for instance, 90% of teenagers and young adults in China and 96.5% of 19-year-old men in Seoul are myopic. Among Japanese school children, the prevalence of myopia is 76.5% in elementary and 94.9% in junior high schools, with high myopia (based on an axial length of 26.0 mm or longer) at 15.2% among junior high students.
Suppressing Myopia Onset and Progression
Life Style Improvement
Daily lifestyle changes can significantly impact myopia progression. Reduced outdoor time and increased near activities, like using smartphones and digital devices, contribute to the myopia boom. Increasing outdoor activities to two hours a day can help prevent myopia onset and progression. Additionally, maintaining a reading distance of more than 30 cm and taking breaks every 30 minutes can mitigate risk.
Protective Treatments
Various protective treatments are available to slow down the progression of myopia, and their usage varies by region. Here are some of the promising methods:
- Low-dose atropine eye drops: Atropine is a medication that dilates the pupil and temporarily relaxes the eye’s focusing mechanism. Low-dose atropine eye drops have been shown to slow down myopia progression. In Japan, these drops are frequently used as an “off-label” treatment.
- Orthokeratology: This involves wearing gas permeable contact lenses overnight to temporarily flatten the cornea, which corrects myopia. This treatment not only allows clear vision during the day without glasses but also is expected to slow down myopia progression.
- Myopia-controlling spectacles: These glasses are designed to create a “myopic defocus” by making peripheral light focus in front of the retina. They have been shown to slow down myopia progression in children by up to 50%.
- Myopic defocus contact lenses: There are two types of these lenses; one provides myopic defocus in the peripheral retina, while the other creates this effect in the central retina. Both types have been effective in slowing down myopia progression in children.
It’s important to note that the choice of treatment can vary greatly depending on the country and its medical practices. In Japan, low-dose atropine eye drops and orthokeratology are commonly preferred methods for controlling myopia progression.
My experiences
In Japan, I frequently examine elementary school students identified with low uncorrected visual acuity during school medical checkups. Some as young as 7 or 8 already have moderate myopia. I assess their lifestyles, such as outdoor time, screen time, and reading distances, and passionately explain myopia control to their parents. However, many parents lack knowledge about myopia control, and some show little interest even after my explanation. This gap in awareness reflects a broader issue in Japan’s conventional wisdom.
Government’s Role
In contrast to countries like China, Taiwan, and Singapore, where national programs address both life-threatening and vision-threatening diseases, Japan’s medical policy appears to focus primarily on the prevention of life-threatening diseases such as hypertension, diabetes, cardiovascular diseases, and stroke. This focus has unfortunately led to a notable absence of a national strategy for the prevention of vision-threatening diseases like myopia. The lack of proactive measures in this area is evident in the insufficient myopia prevention initiatives in schools. It is imperative for Japan to expand its medical policy to include comprehensive strategies for preventing both life-threatening and vision-threatening diseases, thereby ensuring a more holistic approach to public health.
Parental Action for Myopia Control:
Given Japan’s national policy, educating parents about myopia control is crucial. Merely explaining the control measures in a doctor’s office is insufficient. Collaboration among parents, teachers, and ophthalmologists in a grassroots movement is necessary. It is vital for adults to understand the importance of myopia control and take proactive steps.