Nearsightedness, or myopia, is a very common problem that makes it hard to see things across the room and far away. Usually, myopia occurs because the eyeball grows too long during childhood. But there are other causes, too.
Why is my child nearsighted?
Heredity is a factor for myopia, but not the only one. If both parents are nearsighted, there is a greater risk that their kids will be nearsighted, too. Children who spend a lot of time engaged in near activities (reading, using hand-held electronics, etc.) appear to have a greater risk of becoming nearsighted. Research also shows spending more time outdoors lowers the risk of childhood myopia.
More people are becoming nearsighted.
In the early 1970s, only 25% of Americans were nearsighted. Today, the prevalence of myopia in the U.S. is about 42%. Myopia is even more prevalent in Asia. In some countries, up to 80% of the population is myopic.
The severity of nearsightedness is often categorized as: mild (-0.25 to – 3.00 D), moderate (-3.25 to -6.00 D) or high (-6.25 or higher). The power of prescription lenses is measured is diopters (D). Lenses that correct myopia have a minus sign (-) before the power number. For most nearsighted children, myopia gradually worsens, so they need stronger glasses with thicker, heavier lenses year after year.
Cataracts: Most cataracts are associated with the aging process, so nearly everyone who lives long is at risk. But cataracts tend to develop sooner in nearsighted eyes.
Glaucoma: Nearsighted people have a two to three times greater risk of glaucoma, according to an Australian study. Glaucoma is usually due to high pressure in the eye, which damages the optic nerve and causes vision loss.
Detached retina: Nearsightedness increases the risk of retinal detachment – and the higher the myopia, the greater the risk. If the retina pulls away from the eye’s supportive tissue, permanent vision loss can occur.
What you can do.
Fortunately, new research is showing there may be ways to slow the progression of myopia in children. Ask your eye doctor for details – you might be able to keep your child’s eyes from getting worse!