Myopia

What Is Myopia (Nearsightedness)? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Sara Altshul
By Medically Reviewed by 
Reviewed:
Medically Reviewed
Myopia, or nearsightedness, is one of the most common eyesight problems. People with this condition can’t focus their eyesight on far-away objects, which makes distant objects appear blurry, while close objects still appear sharp, according to the Mayo Clinic.

According to research, it’s estimated that nearsightedness affects 40 percent of all people in the United States.

Signs and Symptoms of Nearsightedness

Nearsightedness may develop gradually or quickly. Nearsightedness usually starts between ages 6 and 14 and gets worse until your early twenties, when it often levels off, according to the National Eye Institute.

Symptoms of nearsightedness may include:

  • Distant objects appearing blurry
  • Needing to squint in order to see clearly
  • Headaches
  • Eye strain

Causes and Risk Factors for Nearsightedness

Most commonly, nearsightedness is an anatomical issue, resulting from an eyeball that’s too long, which prevents light from focusing directly on the retina (the “screen” at the back of your eye). Nearsightedness can also be caused by a cornea (the clear layer at the front of the eye) that’s not shaped correctly.

These two problems prevent light from focusing directly on the retina. Instead, light focuses in front of the retina, which makes distant objects appear blurry.

Although researchers still don’t know exactly why some people develop nearsightedness while others don’t, it’s possible that the condition may be genetic. If one or both of your parents is nearsighted, your chances of having the problem are higher than those of someone whose parents aren’t nearsighted, notes the American Optometric Association (AOA).

Some research suggests that spending too much time indoors may be a cause of increasing myopia rates among children.

The condition may also emerge in adulthood, due to factors such as visual stress (which can be caused by close-up activities such as reading or computer work).

How Is Nearsightedness Diagnosed?

A complete eye exam by an optometrist can easily detect nearsightedness.

Often, school vision tests will be the first time a parent learns about a child’s nearsightedness.

Occasionally, parents or teachers will detect nearsightedness after seeing a child squint in order to see distant objects.

Adults may begin to realize they have the condition when they have trouble watching movies, can’t see distant objects clearly while driving, or participate in other activities that involve looking at faraway objects.

If you’re having trouble seeing things that are far away, it’s a good idea to get an eye exam.

According to Mayo Clinic, even if you have no symptoms of nearsightedness, nor a high risk of developing more serious eye diseases, it’s a good idea to get an eye exam:

  • Every 5 to 10 years between ages 20 and 40
  • Every two to four years between ages 40 and 54
  • Every one to three years between ages 55 and 64
  • Every one to two years starting at age 65

But if you’re at high risk for certain eye diseases such as glaucoma, or if you have diabetes, you should have an eye exam every one to two years starting at age 40.

Prognosis of Nearsightedness

There’s no cure for myopia, but wearing glasses or contact lenses can correct simple myopia.

Regular eye exams can lead to better outcomes by allowing ophthalmologists (eye doctors) to find and treat any complications that may develop. And certain lifestyle modifications can keep myopia from getting worse, including limiting screen time, taking screen breaks, spending time outdoors, and quitting smoking.

Duration of Nearsightedness

Myopia tends to emerge in school-age children, according to the AOA, and continues progressing as the eye grows, until around the age of 20.

For most people with myopia, the condition stabilizes by age 20, but in some cases, it continues advancing as people age.

Treatment and Medication Options for Nearsightedness

The simplest treatment for nearsightedness is wearing corrective lenses, either eyeglasses or contact lenses. Another treatment option is surgery. Three common surgeries include:

LASIK (Laser-Assisted In-Situ Keratomileusis) In this procedure, an ophthalmologist first cuts a round, hinged flap in your cornea.

Using an excimer laser (which, unlike other lasers, produces no heat), the doctor will remove layers from the center of your cornea to change its shape and improve your vision.

LASEK (Laser-Assisted Subepithelial Keratectomy) In this procedure, the doctor works only on the cornea’s thin outer layer (epithelium).

After creating a flap, the doctor then uses an excimer laser to reshape the outer layer of the cornea.

PRK (Photorefractive Keratectomy) In this procedure, which is similar to LASEK, the epithelium is completely removed by the doctor.

After using the laser to reshape the cornea, the doctor does not replace the epithelium, which grows back and conforms to the new shape of the cornea.

Complications from these surgeries may include:

  • Under- or overcorrection of your original vision problem
  • Vision problems, such as halos or other effects around bright lights
  • Dry eye
  • Infection
  • Corneal scarring
  • Vision loss (in rare cases)

Medication Options

A study published in 2017 revealed that daily doses of low concentration atropine eye drops can effectively prevent the onset of nearsightedness, without causing significant side effects.

The researchers aren’t sure exactly how atropine affects myopia, but they hypothesize that the medication may stimulate the release of dopamine in the eye.

Clinical trials are currently looking at the effectiveness and safety of atropine drops for children. Research is ongoing but it appears that low-dose drops may help slow the progression of myopia in kids.

Nonmedical Therapies

Orthokeratology is a nonsurgical option for treating myopia. Also known as Ortho-k or corneal refractive therapy (CRT), it consists of wearing rigid contact lenses designed to gradually flatten the curvature of the cornea. As a result, the eye changes how it focuses light. The contacts are worn for brief periods of several hours — when you’re sleeping, for example. During the day, the contacts are removed, and vision may be temporarily clear.

People with myopia due to visual stress can also use vision therapy, reports the AOA. Through various eye exercises, a poor ability to focus can be improved, and clearer distance vision regained.

Prevention of Nearsightedness 

The AOA notes that children who are at high risk of progressive myopia (due to family history, early age of onset, and long periods of close-up work) may be able to slow the progression with bifocal glasses or contact lenses, orthokeratology, eye drops, or a combination of these.

Results of a clinical trial funded by the National Eye Institute and published in 2020 found that myopia progression was slower in children who wore multifocal contact lenses.

Clinicians in Taiwan have identified spending time outdoors as a preventive measure for myopia in children.

You can maintain your eye health by avoiding or limiting activities that lead to eye strain, such as time spent on digital devices.

Complications of Nearsightedness

Possible complications include:

  • Retinal Detachment Compared with people with hyperopia (farsightedness), people who have myopia are considered to be at higher risk for experiencing a retinal detachment, and the risk is greater with increasing degree of myopia.
  • Glaucoma Patients who are nearsighted are also more likely to have most types of glaucoma than those who are farsighted.
  • Blindness The link between myopia and both retinal detachment and glaucoma also makes degenerative myopia a leading cause of blindness in the United States.
  • Cataracts Having high myopia (see Related Conditions below), an increasingly prevalent condition, also ups someone’s risk of glaucoma and retinal detachment, as well as premature development of cataracts, according to the National Eye Institute.

Research and Statistics: Who Has Myopia?

A widening body of research indicates that myopia is becoming increasingly prevalent in the United States and around the world, according to the National Eye Institute. In the coming decades, the upward trend is projected to continue.

According to the AOA, the number of children with myopia is increasing: One-quarter of parents have a nearsighted child, and about 75 percent of nearsighted children were diagnosed between ages 3 and 12.

BIPOC and Nearsightedness

Black Americans represent 7 percent of U.S. myopia cases, an increase of 1 percent between 2000 and 2010, according to the National Eye Institute.

Hispanic Americans represent 8 percent of U.S. myopia cases, a 3 percent increase between 2000 and 2010.

Of those on Medicare, Black and Hispanic Americans are less likely than white, non-Hispanic Americans to have had an eye exam recently, according to the Centers for Disease Control and Prevention (CDC). In 2018, the latest year for which CDC data is available, both Black and Hispanic Americans were about 35 percent likely to have had an eye exam, compared with 44 percent of Asian Americans and 47 percent of the white, non-Hispanic population.

The progression of myopia appears to be a specific concern for people of East or Southeast Asian descent. A study published in 2020 looked at data from 11,000 children with myopia and found that of the following groups — white, Black, Hispanic, South Asian, East or Southeast Asian, Other Asian, and other or unknown — Asian American children were at significantly higher risk for progression of myopia than any other group.


Related Conditions of Nearsightedness

High Myopia This rare, inherited type of high-degree nearsightedness occurs when a child’s eyeballs grow longer than they should or the cornea is too steep. Depending on the severity, high myopia can be corrected with eyeglasses or contact lenses, and in some cases, surgery. It may raise the risk for cataracts, detached retinas, and glaucoma later in life.

Degenerative Myopia This form of myopia is relatively rare but, as noted above, it’s a leading cause of legal blindness, as it damages the retina.

Resources We Love

Favorite Orgs for Essential Myopia Info

National Eye Institute (NEI)

The NEI gives readers detailed background information on myopia, from risk factors to prevention including a description of what exactly goes wrong in eye development to cause the condition. The site also presents current research around myopia, including its own National Institutes of Health–funded studies and clinical trials.

Mayo Clinic

A nonprofit with a broad reach into clinical practice, education, and research, the Mayo Clinic provides extensive, patient-friendly background on myopia. Treatments for nearsightedness are presented clearly and are regularly updated, so readers will find actionable guidance. Those who have upcoming ophthalmologist visits can also read advice on how to prepare and what questions to ask the doctor.

American Optometric Association (AOA)

The AOA represents more than 44,000 doctors of optometry in the United States and is an authority on eye care and optometry. The website covers the essentials of myopia, such as diagnosis and various treatments.

Additional reporting by Sarah Amandolare.

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