What is myopia?
Myopia is blurry long-distance vision, often called “short-sighted’’ or “near-sighted”. A person with myopia can see clearly up close – when reading a book or looking at a phone – but words and objects look fuzzy on a blackboard, on television or when driving. But a pair of glasses aren’t the whole story.
The prevalence among Australian 12 year olds has doubled in 6 years. Myopia in kids tends to progress or get worse throughout childhood, and higher levels of myopia are associated with higher eye disease risks in adulthood. If your child already wears glasses, you can do something to stop their vision worsening. If they don’t you can assess their risk of developing myopia.
Myopia occurs when the eyeball grows too quickly in childhood, or starts growing again in adulthood
Childhood onset myopia is most commonly caused by the eyes growing too quickly, or continuing to grow after age 10-12 when eye growth should normally cease. Genetics, environment and the individual’s characteristics can all contribute to this excess growth
In younger children, myopia progresses more quickly because their eyes are growing at a faster rate, leading to higher levels of myopia, stronger glasses and more eye health risks
Adult onset myopia usually occurs as an adaptation to fatigued eye focusing muscles due to a significant increase in close work, such as university studies
Why should I be concerned?
Myopia is becoming more common in children around the world – the prevalence among Australian 12-year-olds doubled between 2005 and 2011
The average age for developing myopia is reducing – younger onset means faster and more eye growth, which increases likelihood of high myopia and higher risk of eye diseases such as the following:
Retinal detachment – the light sensitive ‘film’ lining the back of the eye pulls away from its base, causing distorted vision or blindness depending on its location
Myopic macular degeneration – loss of central vision clarity, like having a thick smudge permanently in the middle of your vision
Glaucoma – increased pressure in the eye which damages peripheral vision, called the ‘sneak thief of sight’ as very few people who have it notice its symptoms until it is very advanced
Cataract – a cloudy window in the middle of the eye, like looking through a foggy windscreen
The average cost of glasses or contact lenses amounts over lifetime for a myopic person is likely to be in excess of $50,000. Higher myopia reduces quality of life and is more costly to correct with glasses and contact lenses
What causes myopia?
Spending more time on close work has been linked to development of myopia, such as reading, playing computer games, drawing or using smart phones and tablets
Electronic hand held devices are easy for toddlers to use resulting in increased exposure to close work at a younger age
Myopia can be hereditary, and a person’s ethnicity and family background can increase the risk
Research suggests a link between Asian ethnicity and faster progression of myopia, with higher worldwide prevalence in this group of people
A person with one short-sighted parent has three times the risk of developing myopia – or six times the risk if both parents are short-sighted
Some studies show that children are more likely to be short-sighted if their parents finished high school or went to university
Under or over-corrected vision (incorrect glasses, or having no glasses when they are needed) has been shown to promote onset and accelerate progression of myopia
How can I prevent or slow myopia?
Catching early signs of myopia before it fully develops can help slow onset and progression
Children should not spend more than three hours a day – in addition to school time – on close work such as reading, homework or screen-time
When using a computer, ensure it is properly positioned to avoid eye strain and take breaks every 20 minutes by looking across the room for 20 seconds
Smart phones are popular for children and teenagers’ texting, social media, reading and games – but too much screen time is linked to myopia, can cause dry eyes, and increase risk of eye damage and diseases in adulthood similar to UV damage
The blue-white bright light from tablets and phones can damage long-term eye health and affect sleep – while there are no guidelines yet on how much to limit a child’s overall time spent on screens, these devices should be avoided by children and adults for three hours before bedtime
Outdoor sport and play of at least 90 minutes a day can reduce the risk of myopia – looking at your tablet or phone when outside doesn’t count!
There is evidence to suggest that exposure to outdoor light is beneficial in slowing onset and progression of myopia – but UV protection is still important so wear sunglasses and a hat
My child is already myopic!
Specialty contact lens designs and orthokeratology currently offer the best vision correction options to slow progression of myopia
Research has shown that specially designed glasses lenses are effective at slowing progression of myopia, though not to the same degree as contact lenses, and only for particular individuals with eye muscle teaming problems
Atropine eye drops have been shown to slow progression of myopia and their use is gaining popularity
