Article from Philip Cheng, B.Optom (Melb) Ocular Therapeutics (Australia)
With friendly permission from Philip Cheng
“We’ll take his iPad away”, says his father after learning how much worse his son’s eyes have worsened in one year.
The iPad. We all have one. Many children use it daily. Some schools even require kids have one.
The prevalence of childhood short-sightedness (myopia) around the world has skyrocketed in the past decade. The original iPad was released in 2010, some 8 years ago.
Is it a mere coincidence, or is the iPad to blame for today’s childhood vision issues?
While it’s easy to blame the iPad, and other similar electronic devices, smartphones and tablets, there’s a bit more going on than that.
Recently I saw an elderly lady in my clinic who was severely short-sighted. I asked her if myopia was something that ran in her family. She said both her parents never wore glasses. Back in her youth, there was no iPad. There were no computers, or even TVs. Then she said she was an avid reader.
Near work. Whether it’s reading, writing, playing on a tablet, tutoring sessions, learning a musical instrument, or computer games, these close-up activities increase the focusing demands on the eyes. Too much of this can cause eye discomfort. Especially for children whose eyes have a tendency to misfocus at close range or difficulties with eye teaming—the efficient use of both eyes together as a team—who are more prone to experiencing eye strain. Some of these near focusing issues, if not detected and corrected by an optometrist, can lead to increasing myopia.
And where to most people, and children, do this type of near work for extended periods of time? Indoors.
Development of myopia is closely linked to spending too much time indoors. In contrast to farther viewing distances in outdoor open spaces, a more confined indoor environments force the eyes to focus at relatively shorter distances while, at the same time, place blurred images of objects onto the peripheral parts of the back of the eye, the retina.
This blurred focusing in the peripheral retina is termed ‘hyperopic defocus’. Myopia occurs when the eye physically grows too long. Proper modulation of eye growth during childhood and adolescence can be adversely affected by signals caused by retinal hyperopic defocus. Research in recent years have found this phenomenon to be associated with an increase in eye elongation, resulting in the development and progression of myopia.
Indoor light is also many magnitudes dimmer than outdoors, even on a cloudy day. Light levels outdoors under bright sunlight is around 200 times greater than typical indoor lighting. Sunlight have been suggested to have protective effects against myopia developing in children. While the exact mechanism is not yet clear, it may be related to the stimulation by sunlight of a neurotransmitter in the brain called dopamine, which in turn keeps the growth of the eye in check.
In China, where the prevalence of childhood myopia is at 80%-90%, there are schools experimenting with glass-walled ‘Bright Classrooms’ to simulate outdoor lighting conditions inside where the students spend most of their days. It is believed that increasing children’s exposure to sunlight can help combat their myopia epidemic.
Here in Australia, parents should ensure to balance their child’s near work with spending more time outside, walking the family dog, playing sport, going to the park.
As an optometrist, I recommend that all children spend at least 90 minutes outdoors each day to take in a good dose of sunlight (remembering to use UV protection — a hat and some sunnies), and after every 30 minutes of concentrated near work they should take a short break, look outside and rest their eyes. And when they are reading, make sure they don’t hold their book right up their nose—always maintain at least an elbow’s distance between the book and their eyes.
So no, it’s not just the iPad and taking it away isn’t the magic solution. The rise in myopia appears to be linked to all the near work children are doing these days — the increase in education pressures from a younger age than in any previous generations — and not enough time spent outdoors.
We can’t remove the books, avoid technology, or tell our kids not to study. Schooling is important and near work is inevitable, but balancing the amount of time children spend inside with more time outdoors, and forming good habits when reading and studying, is a good way of helping prevent their eyes from getting worse.
And, of course, have your child’s eyes checked regularly. Children with myopia should be examined as often as every 6 months as they may progress rapidly. If your child’s level of myopia is increasing, there are now treatments that optometrists can prescribe that can effectively slow down, or even stop, their progression. So it’s worthwhile asking us how we can help.
Philip Cheng is a clinical optometrist in Melbourne, Australia. Trained at the University of Melbourne and with over 15 years of experience, he is the director of Eyecare Concepts | The Myopia Clinic (www.themyopiaclinic.com.au) where he provides comprehensive myopia care for children and teenagers. He has a keen interest in children’s vision, orthokeratology, specialty contact lenses and myopia management.
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