What is myopia or nearsightedness?
Nearsightedness or myopia (Mai-ow-pee-uh) is a common vision condition that affects your kid's distance vision. Near objects can be seen well, but distant objects may look blurry. It usually starts at school age and stabilizes when your kid develops into an adult.
It occurs when light rays are focused in front of your kid’s retina instead of on the retina. This is usually due to abnormal elongation of the eyes during growth, leading to focal length mismatch.
How to pronounce myopia? Listen to the audio.
What are the symptoms of myopia or nearsightedness?
You may notice the following behavior if your kid has myopia.
- Persistently squint, especially looking at distant objects
- Blink excessively or rub their eyes frequently
- Consistently moving close to the television
- Reading books or doing homework abnormally close to the face (closer than 25 cm)
Your kid may also tell you:
- Things or texts seemed blurred or fuzzy
- They couldn’t see what was on the whiteboard
- Their eyes felt sore from time to time
- They may complain of having headaches
Younger children may not express difficulty seeing. In addition to the above behaviors, the following behaviors in school may also be signs of myopia.
- Your kids couldn’t stay still in their seats. (To get closer to the whiteboard)
- They seemed disinterested or having trouble focusing in class
- A lot of misspellings in schoolwork or notes
- Worsening of school grades compared to prior years
What is the cause of myopia or nearsightedness?
In myopia or nearsightedness, near objects can be seen well, but distant objects may look blurry. For kids with myopia, the shape of their eyes becomes too long from front to back (oval-shaped). This leads to light being refracted to focus in front of the retina, instead of on the retina when it passes through the cornea into the eyes. And it results in light signals translated by photoreceptor cells to the brain being perceived as blurry.
What are the risk factors for myopia or nearsightedness?
The following risk factors may increase the likelihood of developing nearsightedness.
- Genetics: Research indicated that if you have myopia, your kid's chance of having myopia is 1.5 to 2.1 times higher. If both parents have myopia, the likelihood increases to up to 3.0 times.
- Prolonged close-up activities: Prolonged close-up activities are associated with an increased risk of myopia. Activities include reading, studying, or even playing with Legos. Research showed that was also a causal association between more education and myopia.
- Smart device screen time: Studies indicated that children who use computers or smart devices for a prolonged period of time are more likely to develop myopia and see myopia worsening.
- Lack of time spent outdoors: Strong evidence showed that time outdoors is an important risk factor in the development of myopia and its progression.
Can myopia or nearsightedness cause blindness?
Myopia or nearsightedness is an inconvenience that can be easily corrected with eyeglasses, contact lenses, or surgery. However, myopia increases the likelihood of uncommon but serious sight-threatening complications, such as myopic macular degeneration (MMD), retina detachment (RD), cataracts, and glaucoma. These complications may lead to legal blindness if not timely treated.
Overall, myopic patients had 100 fold higher risk of MMD, a three-fold higher risk of RD, a three-fold high risk of cataracts, and an almost two-fold increase in the risk of glaucoma. Studies indicated that the higher the spherical errors (in diopters), the higher the risks of these complications.
Learn more about how myopia may lead to vision-threatening complications.
When does myopia or nearsightedness stop worsening?
In a normal eye, babies are born hyperopic or farsighted. And within the first year, then slower later, their eyes' axial length growth matches the focal length of the cornea to the retina, which is called emmetropization. In children with myopia, the growth of the eyes, or the elongation of the axial, doesn’t match the focal length and overshoots emmetropization.
Myopia can begin at any age, but most start at the school age of 6 to 14. Even though there is no firm consensus on when myopia stops progressing, a key myopia study in 2013 found that the mean age at myopia stabilization was 16 years, with the following breakdown:
- Age 15 years, 48% had stable myopia
- Age 18 years, 77% had stable myopia
- Age 21 years, 90% had stable myopia
- Age 24 years, 96% had stable myopia
It’s also possible for older kids or teenagers to be diagnosed with myopia, which may be due to increased constant visual stress such as time spent studying. Eye experts believe that your focusing muscles in the eye may get stuck in “near gear” from overusing them this way.
Spending more years in full-time education is associated with a greater risk of developing myopia.
How is myopia or nearsightedness diagnosed?
Your eye care specialist will begin by asking about your child’s medical history, reading/study habits, and if you or your spouse have myopia. They will then do some basic eye tests.
Eye chart tests
Your child’s eye doctor or healthcare professional is likely to start with an eye chart or visual acuity test. An eye chart test is to check how sharp your vision is at a distance. Letters and symbols of different sizes will be shown, and your kid will be asked to read them.
If your kid needs vision correction, it's important to find out how much correction is needed for each eye. This is called measuring your "refraction."
Your kid’s doctor may start off using a machine to measure refractive errors using an autorefractor. Then, the doctor can objectively assess how the light acts as it enters the eye and onto the retina.
B) Phoropter test
Your kid will be asked to read an eye chart again. But he will be looking through a device with different lenses called a phoropter this time. By having them look through the phoropter at an eye chart, your eye doctor could find out the correction needed for their myopia by switching lenses on the instrument rapidly. This will help your eye doctor accurately determine the prescription from your kid’s input.
Your kid’s eye doctor may also conduct additional tests to examine the condition of the eye structure, response to light, eye movement, side vision, eye pressure, retina, and optic nerves.
Can myopia or nearsightedness be cured?
There is no cure for myopia. The goal of treating myopia in children is to improve vision by using corrective lenses and prevent abnormal eye elongation from worsening. Wearing prescription eyeglasses or contact lenses helps the eye to focus light correctly, so your kid can see clearly. Having myopia control treatments reduce the likelihood of vision-threatening complications.
Surgical treatments, such as LASIK or even intraocular lenses, are not recommended for kids since they are still growing. However, they can be effective treatment options after reaching their 20s and when their myopia is no longer progressing.
What treatments are available to prevent myopia or nearsightedness from worsening?
You can slow or stop your child's myopia from worsening with the following interventions.
Medication and corrective lenses
Atropine is one of the most effective treatments for preventing myopia from progressing. However, because the concentrations commonly used for myopia control are not commercially available, parents need to purchase the low-dose atropine from the prescribing doctor’s clinic or a compounding pharmacy.
Contact lenses. Dual focus soft contact lenses, e.g., MiSight daily disposable contact lenses, were shown to have a moderate effect slowing myopia from progressing while correcting the refractive errors.
Glasses. Several myopia control glasses are available outside of the US, e.g. Miyosight, Stellest, and MyoVision. They were shown to be effective and are great options for younger kids.
Orthokeratology. Through the use of specially-designed hard contact lenses that are worn overnight, your kid’s corneas are temporarily reshaped throughout the day. This means that their vision will return to normal during the day. Further, studies indicated that this therapy is effective in slowing the progression of myopia.
Go outdoors in the daylight. Get two (2) hours of daylight every day. Some appropriate activities include sports, gardening, a walk around the neighborhood, trail hiking, or even a picnic. (Download an outdoor activity tracker)
Take a break. Myopia worsens if your kid keeps near focus for too long. For every 20 minutes looking at a screen or near work/reading, relax for 20 seconds by looking at an object 20 feet away. This is also known as the 20-20-20 rule.
Use digital devices appropriately. Limit device screen time to less than two (2) hours, including television, smartphones, and tablets. Furthermore, hand-held device's viewing distance should be about 12” (30 cm) from the eyes.
Potential questions to ask your eye care professional
a. First-time myopia control contact lens wearer
- How long should my son wear his myopia-control contact lenses each day?
- How many days per week should my son wear his contact lenses?
- What should my son do if he accidentally falls asleep while wearing his contact lenses?
- What should my son do if he accidentally drops a contact lens? how to clean it?
- What should my son do if he experiences redness or irritation while wearing his contact lenses?
- What should my son do if he experiences dryness, discomfort or other complications while wearing his contact lenses?
- How and where should we store the contact lenses?
- How many months of supply would you recommend I purchase at this time considering kids' prescription does change? Can I exchange the unused ones?
- How often should my son come back for check-ups?
- What discount do you have for the contact lenses?