The rate of myopia in children is increasing, both here in Hong Kong and elsewhere. We hear the details – and some ways to combat the problem – from Optometrist ANDY MEAU, founder and director of iSight Optometric Eye Care Center.
One of your specialties is controlling myopia in children; what is myopia?
It’s a physical elongation of the eyeball, where light is focused in front of the retina rather than directly on it. Typically, babies are born with short eyeballs, which grow to normal adult size by age six or seven. Sometimes, this growth can become too fast, and the eyeball can become too long, leading to the onset of childhood myopia. If left uncontrolled, there is an increased risk of developing vision-threatening eye diseases in the future, such as glaucoma and macular degeneration.
Who gets myopia?
We know that children of different ethnicity have a different risk of developing myopia; the risk is higher among Asians, for example. Myopia onset also correlates with the amount of time spent indoors and the amount of “near work”, which includes screens, books and so on. Poor posture and poor environmental lighting are also risk factors.
Genetically, a person with a myopic parent has three times the risk of developing myopia – six times if both parents are myopic. The prevalence of childhood myopia has nearly doubled in the last 10 years; in Hong Kong, the rate is around 20 percent in six year-olds, 60 percent in 12-year-olds, and nearly 85 percent in university students. I’ve definitely seen exponential growth of myopia in children year on year for the past 15 years – no surprise, in view of how much more time is spent on screens.
We do a lot more preventive coaching these days, even when a child doesn’t have any signs of myopia. This allows us to set up goals to reduce the risk. Here are tips I offer the parents to slow down progression and delay the onset of myopia.
- Spend more time outdoors; at least one hour per day is recommended.
- Reduce screen time; ideally, children under three years shouldn’t be exposed to screens. Between three and five years, a child should be exposed to less than an hour of combined screen time per day. In primary school, less than an hour a day is not realistic, so we recommend the “20-20-20” rule. For every 20 minutes of near work, the eyes should be rested for 20 seconds by looking at something more than 20 feet away. The idea is to relax the focusing muscles in the eyes, so they don’t become overly tense.
- Posture is important. When a child is doing homework, they should be properly seated and at an appropriate height – not leaning down to read, for example.
- Ensure the lighting environment in a room is bright and diffuse, so as to provide even lighting over the reading material.
Have you noticed changes in your patient profiles as a result of COVID-19?
Before COVID, about half of my patients were kids; but because of the change to online learning, I’ve definitely noticed a significant increase in vision problems among children. These aren’t just confined to eyesight problems; there’s also been an increase in visual function problems, including “accommodative function” (accuracy of focusing) and “binocular function” (whether the two eyes work as a team).
In order for a person to see or read properly, these two systems need to work seamlessly without conscious effort. When they’re out of sync, a child can struggle to focus on books or screens, or to maintain focus on near objects long enough to complete homework.
I’m seeing more and more cases where a child has 20/20 vision, but cannot adequately adjust their focus. Symptoms can include headaches from eye strain, words “swimming” on the screen, skipping words when reading, or a general reluctance toward reading. These problems can go undetected if not examined properly; sometimes parents may even think their child is lazy or lacking attention.
One example I’ve seen is an eight-year-old girl who couldn’t read small print properly, not because of an eyesight issue, but because the accommodative muscles weren’t functioning properly. Contrary to her parents’ thinking, glasses weren’t the solution. We prescribed a three-month course of vision training to retrain the muscles to work properly; she’s now able to read properly and can change focus quickly. Her parents even told me she’s become an avid reader.
What are “blue” glasses and are they effective?
Recently, there has been a lot of interest in glasses that block blue light. Blue light is part of the visible light spectrum, and many modern digital devices such as tablets, smartphones and flatscreen TVs emit a lot of this type of light. Our eyes aren’t good at filtering out blue light, and ongoing research shows that it could potentially cause changes to the macular area of the retina. Digital eye strain is another issue.
For this reason, eyeglass lenses with blue light filters are recommended for children or adults who need to spend excessive amount of time on screens. These filters are available for both prescription or non-prescription lenses; however, I’d caution against buying off-the-shelf blue-light-filter glasses as they’re not all manufactured using optical lenses.
What are some general things we can do to keep our eyes in good condition?
A balanced diet, less screen time and more outdoor time (using UV protection) are all beneficial to maintaining the health of our eyes. Routine eye examinations are essential to prevent our eyes from developing eye diseases, too. In general, I recommend children to have an eye examination at least once a year from age four. In our 20s and 30s, every two years is recommended. And, since our eyes experience most changes in our 40s, I’d recommend an annual examination from then.
What do you like to do when you’re not working?
Any spare time that my wife and I get is 100 percent occupied by our five-year-old son! We enjoy riding our bikes, swimming or generally spending time outdoors, picnicking and visiting far-flung places in HK. I was an avid scuba diver in my BC (“before child”) days, and enjoyed dive trips to different parts of Asia. And I’m always a sucker for a game of bar pool, and generally just enjoy good food and drinks with friends.
About Andy and iSight
Hong Kong-born Andy grew up in the US, completing high school in Massachusetts and college in Pittsburgh. After moving back to HK, he enrolled in a five-year course at Hong Kong Polytechnic University School of Optometry, then worked at a private optical shop in Central. He opened iSight in 2011. The clinic offers comprehensive eye exams, myopia control treatment for children, dry eye assessment and treatment, normal and advanced contact lens fitting, glaucoma screening, diabetic retinopathy screening, marine and transport department vision certificates, and more.
This article first appeared in the Spring 2021 issue of Expat Living magazine. Subscribe now so you never miss an issue.