Eye Health Resources

Understanding high myopia and its causes

Jump to:

Myopia 101

The fundamentals of myopia

Before we get into high myopia, let’s start with what myopia is. Myopia is a chronic, progressive disease where the eye grows too long from front to back. This lengthening of the eye makes it harder to focus on things that are far away. In other words, things that aren’t up close appear blurry.¹ This lengthening of the eye also increases the chances of eye complications later in life because a longer eye means more strain on delicate structures like the retina (part of the eye that turns light into what you see). As you may have guessed, high myopia is a more severe version of myopia—meaning the eye has grown longer than is average the risks to the health of the eye are higher.

Defining high myopia and extreme nearsightedness

An eye doctor measures severity of myopia by determining your prescription (how much vision correction is needed to give you clear vision), which is measured in diopters (D). When the eye is less elongated, the prescription will be closer to zero. When the prescription goes above -5D, that’s when you’re considered to have high myopia. The more severe the myopia, the blurrier the distance vision and the higher likelihood of complications later in life. While there is no upper limit to how high a myopia can go, cases rarely go above -10D.

Symptoms

The effects of high myopia

Uncorrected high myopia can be a serious challenge

Myopia doesn’t start as high myopia, it progresses into high myopia as the eye continues to grow in childhood. That’s why it’s so important to catch early—then the eye doctor can come up with a myopia management plan and potentially slow progression. Myopia is often discovered via the most obvious symptom: Blurry distance vision such as when a child is struggling to see the board in school.

Extremely blurry distance vision

Things that are more than a few feet away may look very blurry and hard to distinguish. At high levels of myopia, simple things can become more difficult and dangerous— like avoiding tripping hazards on a nature trail or navigating to the bathroom at night.

Poor depth perception

Since things that aren’t very close by are so blurry, it can become very hard to judge exactly how far away things are. This can present problems with tasks like driving, crossing the street, hiking and more.

Headaches and frequent eye strain

People with uncorrected high myopia squint to help them see many things in their everyday life, like street signs and the faces of those around them. This squinting and difficulty focusing can cause headaches and feelings of eye strain.

Possible risk factors of high myopia

Myopia can be caused by both genetic and environmental factors, but experts often can’t predict whether a person will progress to high myopia. Typically, the earlier a child develops myopia, the more time it has to progress, and the more likely they are to develop high myopia. That's why it's so important to have yearly comprehensive eye exams—that way you can potentially catch it early on and get started with myopia management to help slow progression.

Genetics

If one or both of your parents have high myopia, there’s a greater chance you will, but you may end up with high myopia even if your parents don’t have it.

Environment and Habits

Too much time spent indoors may increase a child’s risk of developing myopia
Spending too much time doing close-up activities like reading or using computer screens can also increase your risk.

Eye Health Risks

No safe level of myopia

What happens when the eye grows too long? Well, in addition to causing blurry distance vision, the lengthening of the eye strains its delicate structures, leading to complications later in life. This is why even though high myopia has the highest eye health risks, there is no safe level of myopia. Even lower levels of myopia could pose an increased risk of eye issues. For example, every diopter increase in myopia (say, from –2D to –3D) increases the risk of myopia macular degeneration by 67%. The most common complications associated with myopia are:

The retina thinning with age, which can lead to tears, holes and/or retinal detachment
Increased eye pressure, which may lead to glaucoma
Higher likelihood of developing cataracts
Eyes injure more easily
Increased risk of permanent vision loss

Treatments

How to correct high myopia

Living with high myopia can be quite difficult if it goes untreated, because anything that isn’t very close to your eyes may be very blurry. This can make it challenging to do even the simplest tasks, like reading the board at school or seeing street signs. Some of the most common treatment options include:

Eyeglasses
Contact lenses
Laser eye surgery

While these treatments help correct the nearsightedness of myopia, those with high myopia should plan on seeing their eye doctor annually because of the increased risk of other eye complications.

Find an Eye Doctor

Slowing or preventing the progression of myopia into high myopia

While there’s no “cure” for myopia once it develops, there are things you can do that might help reduce the likelihood of developing high myopia or manage its progression.

Time outside

Research shows that spending at least two hours per day outdoors can help reduce myopia onset or slow its progression.⁴

Less “near work”

Reducing the amount of time spent on near work (e.g. reading, tablets) outside of school can help reduce myopia onset.⁵

The 20-20-20 rule

Every 20 minutes, look 20 feet away for 20 seconds when doing near-work activities like reading or homework.⁶

Orthokeratology

Orthokeratology (ortho-k) can help manage myopia and typically provides glasses-free vision correction during the day by temporarily flattening the cornea by wearing a hard contact lens overnight.

Eye drops

Low-dose atropine has been show to slow the progression of myopia in children and teens.^†

Myopia management contact lenses

These special contacts are worn during the day, and have special optics that both help correct vision and manage myopia.

_{† Low-dose atropine is currently not approved by any regulatory body for myopia control. Atropine’s use is considered off-label and is subject to local regulatory, legal and professional requirements that the ECP must understand and comply with to cover all aspects of off-label prescribing in their country.}

Have high myopia? Get your eyes checked regularly.

A person with high myopia has a higher risk of other eye conditions, so the best way to make sure your eyes are as healthy as they can be is to schedule yearly eye exams. This can help you stay proactive about any developing conditions, and help your eye doctor create an appropriate plan.

Find an Eye Doctor

FAQs

Frequently asked questions

What is the highest myopia?

Myopia is typically measured in “diopters,” which is a measurement your eye doctor takes to determine the lens power needed to correct your vision. Technically, there’s no limit to how high or low diopters can go, but anything above -10 is quite rare.

What causes myopia to get worse?

If myopia develops early in childhood, the growth of the child can be a time that also means growth of the eye and worsening myopia. This growth usually levels off around age 20. As the child grows, spending excessive time indoors and doing near work like reading or playing video games may also increase the likelihood of myopia progression. Myopia that’s diagnosed in adulthood is usually due to visual stress or diseases like diabetes and cataracts.

What should I know about managing high myopia in children?

It is critical to monitor children for myopia as they will likely progress overtime and can end up with higher levels of myopia. When myopia is identified, it's important to get them into a treatment that will help manage their progression. Though higher levels of myopia carry a higher risk for complications later in life, there is no safe level of myopia.

Does high myopia get worse with age?

Typically, high myopia continues to progress until your 20s, when the eye growth begins to level off. This is why starting a myopia management plan early on in life is so important—myopia at any level can lead to other serious eye conditions, like cataracts and retinal detachment.

Is high myopia a disability?

High myopia itself is not typically considered a disability. However, it can lead to visual impairment or complications such as retinal detachment or myopic maculopathy. In some cases, it can lead to vision loss or blindness if left unmanaged, and legal blindness is counted as a disability.

Footnotes

Consult your eye care professional for more information. Johnson & Johnson does not provide medical advice; this information is for educational purposes only.

References

Flitcroft DI. The complex interactions of retinal, optical and environmental factors in myopia aetiology. Progress in Retinal and Eye Research. 2012 31(6):622-660.
Flitcroft DI, He M, Jonas JB, et al. IMI-Defining and Classifying Myopia: A Proposed Set of Standards for Clinical and Epidemiologic Studies. Invest Ophthalmol Vis Sci 2019;60:M20-30
Impact of increasing prevalence of myopia and high myopia: Report of the Joint World Health Organization – Brien Holden Vision Institute Global Scientific Meeting on Myopia, University of New South Wales, Sydney, Australia, 16–18 March 2015
Wu PC, Chen CT, Lin KK, et al. Myopia Prevention and Outdoor Light Intensity in a School-Based Cluster Randomized Trial. Ophthalmol. 2018;125:1239-50.
Huang PC, Hsiao YC, Tsai CY, Tsai DC, Chen CW, Hsu CC, Huang SC, Lin MH, Liou YM. Protective behaviours of near work and time outdoors in myopia prevalence and progression in myopic children: a 2-year prospective population study. Br J Ophthalmol. 2020 Jul;104(7):956-961.
Johnson & Johnson Vision. Schedule an Eye Exam: Tips to Prioritize Your Eyes At Home. https://www.jjvision.com/prioritizeyoureyes.

2024PP15858