What Causes Short-Sightedness: Reasons for Myopia Development
Myopia, or shortsightedness, is a common condition that is increasing worldwide. The blurred distance vision associated with myopia can make driving, sports, and other daily activities difficult.
In this guide, we’ll look at how to slow myopia progression and why early treatment and intervention are crucial for managing it.
What Makes Someone Short-Sighted?
Myopia is a refractive error where light rays bend incorrectly. It causes light to focus in front of the retina rather than directly on it. This incorrect focus results from elongation of the eyeball or curvature changes in the cornea or lens.
Simply put, the eye grows too big, causing light to focus in the wrong place on it.
These changes in the eye shape make it easy to see objects close up but distant objects appear blurry.
What Causes Short-Sightedness?
The exact causes of short-sightedness are not fully understood. However, studies suggest that environmental and genetic factors affect myopia development.
Factors that may increase the risk of myopia include:
Genetics — Children are at a greater risk of developing myopia if one or both of their parents are myopic.
Eye Strain — Prolonged near vision work, excessive reading or use of digital devices, excessive screen time, and too much time spent indoors can all cause eye strain. This excessive eye strain can increase the risk of myopia.
Vision Habits — Lifestyle choices can increase an individual’s risk of myopia. For instance, poor reading habits or lack of screen breaks during work can contribute to a higher risk of myopia development.
Environmental Factors — Lack of exposure to natural light by spending too much time indoors can increase the risk of developing myopia.
Genetics
As mentioned earlier, there is a genetic component to myopia development. For instance, if one parent is nearsighted, the child has a three times higher chance of developing myopia. If both parents are myopic, the child’s chance of developing myopia is six times greater.
This study identified a significant positive association between parental myopia and a child's risk of developing myopia. Children with two myopic parents had a higher risk of developing myopia compared to those with one myopic parent. (Source: National Library of Medicine).
Lifestyle Factors
Modern lifestyle choices likely contribute to the increasing prevalence of myopia.
Some of the biggest risk factors of myopia include excessive screen time and near-vision work without adequate breaks.
Taking regular breaks has been recommended and can help manage myopia symptoms.
A commonly held rule, called the 20-20-20 rule, involves;
Every 20 minutes take a break from your near-vision activity
Look at something 20 feet away for 20 seconds
Return to work and repeat this myopia management exercise 20 minutes later
This is, however, now considered to be too conservative. That is, 3 breaks of 20 seconds, or 1 minute of distance viewing every hour, is not sufficient.
External and Environmental Factors
Environmental factors, such as limited outdoor activity, can influence myopia development. Natural light is important for healthy eyes and vision.
Spending enough time outside is a crucial way to prevent myopia development. Research shows that spending enough time outdoors in natural daylight can:
Reduce the risk of myopia development
Reduce myopia from progressing to higher levels
One of the positive benefits from natural light may result from dopamine. Exposure to sunlight stimulates the release of dopamine from the retina. Dopamine helps inhibit eye growth to help slow down the progression of myopia.
Since myopia frequently develops in school-age children, it is crucial to help your child spend more time outside. A simple way to do this is to encourage an additional hour spent outside, and away from screens, every day.
What Causes Myopia to Worsen
Early myopia detection and management can improve quality of life and potentially slow its progression.
Since myopia can worsen during childhood and adolescence, it is important to avoid habits that make myopia worse.
Excessive close-up activities, eye strain, and excessive time indoors can all worsen myopia progression.
To reduce the risk of developing myopia or possibly slow its progression, it is recommended to:
Get regular eye check-ups
Take breaks regularly during near-vision activities, such as reading or using a computer
Include regular breaks from close work
Reduce overall screen time (i.e. using a computer or laptop or staring at a smartphone)
Make sure to spend ample time outdoors enjoying natural light
How to Identify Myopia/Can You Detect Myopia Early
Early detection of myopia ensures the best outcome. Caught early, myopia control strategies can be used to slow myopia progression during peak years and lowers the risk of potentially sight threatening conditions in later life.
Children who develop myopia are at risk of developing progressive myopia and other eye conditions such as glaucoma, cataract, retinal tears, retinal detachment and myopic maculopathy.
Here are possible signs and symptoms of myopia to watch for:
Eye strain
Squinting to see objects clearer
Headaches
Noticing that distant objects look fuzzy or blurred while closer objects appear clear
Fatigue while driving, working, or playing sports
Poor performance in academics
Short attention span
Holding objects as close as possible to your face to see them clearer
If you or your child notice these myopia symptoms, schedule an eye exam. Early detection is key for better myopia management.
Not all children experience obvious symptoms of nearsightedness, it is imperative to schedule regular eye exams for children. Regular eye tests for children are the best way to detect myopia early.
We recommend that you have a routine comprehensive eye test in Perth before your child starts formal school (pre-primary) at age 4 or 5, provided there are no concerns prior to that age.
How to Manage Short-Sightedness
There are several effective options for managing myopia and slowing its development. Corrective measures for myopia include glasses, contact lenses, and potential surgical options.
Myopia progression can be slowed in children and teenagers with early detection and proper management.
One of the easiest and most important ways for young children to slow myopia progression is with plenty of outdoor time.
Along with lifestyle and environmental changes (such as reducing screen time), several effective treatment options can help manage myopia.
We offer a variety of treatments at For Eyes Optometrist to help control the progression of myopia, including:
MiyoSmart Lenses — Miyo Smart corrective lenses are excellent for enabling focus in the central and mid-peripheral vision. Learn more about corrective lenses for myopia here: Myopia Spectacle Lenses: Everything You Need to Know.
Orthokeratology (Ortho-K) — These contact lenses are moulded to fit the unique shape of your cornea to help manage myopia.
Soft Daily Disposable Contact Lenses — These comfortable, daily-wear contact lenses are specifically designed to have a myopia-controlling effect.
Eye Drops with Atropine — Low-dose atropine eye drops can be used to slow the progression of myopia with minimal side effects.
Book an Eye Test to Slow the Progression of Short-Sightedness
Spending time outside, taking regular breaks from close-vision work, and getting regular eye exams are crucial ways to slow or prevent myopia progression.
If you have concerns about your or your child’s vision, book an eye test or consult with one of our Fremantle optometrists. We offer a variety of tailored management options for myopia. Book online through our online form give us a call on (08) 9335 3433.
