Myopia: Signs You Are Nearsighted and Treatment Options
This article describes myopia symptoms, causes, and treatments. It also discusses the diagnosis of myopia and ways to slow its progression, including information about low dose atropine eye drops.
To understand myopia, you need to know a little about vision. Light passes through the cornea, and the lens focuses it before it reaches the retina at the back of the eye. The brain processes the signals from the light into what you see.
With myopia, the slope of the cornea or shape of the lens is different than in someone without a refractive error. As a result, light rays entering the eye do not bend correctly before they interact with the retina. People with myopia may have eyes that are longer from front to back. This makes light passing through the lens land in front of the retina instead of on it, which makes distant objects out of focus (blurry).
Eye doctors typically gauge myopia using a standard unit of lens power known as a diopter. Negative powered prescription lenses can help correct myopia. People who need less than -6 diopters have common myopia. People who need more than -6 diopters have high myopia.
It is not clear why the eyeball grows differently in some people. There is some evidence to suggest that nearsightedness is genetic. Indeed, many people who are nearsighted have parents who are also nearsighted. Myopia most likely results from slight variations in many different genes combined with lifestyle and environmental factors.
Approximately 41.6% of people in the United States are nearsighted, according to the National Eye Institute (NEI). The prevalence is even higher in other parts of the world — namely, in the resource-rich countries of Asia and Southeast Asia.
Nearsightedness typically begins in children between the ages of 6 and 14 years. The refractive error can worsen until they are in their early 20s, when it tends to stabilize.
Children who spend a lot of time outside are less likely to be nearsighted than children who spend more time inside, according to an NEI-funded research study published in 2012. The reason for this correlation is not clear, but it could be related to the amount of light that reaches the eye when outside versus inside.
Other factors and conditions that may increase the chance of myopia include:
- long periods of work requiring overuse of the eyes to focus on close objects
- poor lighting
While myopia is nearsightedness, hyperopia is farsightedness. With hyperopia, objects up close are blurry, and distant objects are clear. With significant hyperopia, vision may be blurry regardless of how far away the items are. This is not to be confused with presbyopia, which is an age-related loss of close-up vision. Like myopia, hyperopia is a refractive error.
Some people have anisometropia, wherein each eye has a different refractive error. Specifically, one eye is nearsighted, and the other is farsighted.
Some common symptoms of myopia include:
- squinting to see clearly
- difficulty seeing distant objects
People can become nearsighted at any age, though individuals who become nearsighted early in life may notice symptoms when they are between 8 and 12 years old.
When to contact a doctor
Contact a doctor for any changes in your or your child’s vision. Myopia usually develops slowly, so it may take some time to notice symptoms. Annual eye exams are essential so that your eye doctor can detect any signs of myopia and treat it as soon as possible.
Since high myopia increases the chance of retinal detachment, glaucoma, and cataracts, people of all ages with high myopia may need more frequent visits to their eye care professional.
Diagnosis starts with your primary care doctor, pediatrician, or optometrist conducting a visual exam that includes reading letters on the standard eye chart. If they suspect myopia, an optometrist uses additional diagnostic measures, including:
- retinoscope to check the reflection of light off the retina
- phoropter to measure the amount of refractive error
The doctor may use eye drops to keep the eye’s focus static during testing.
Treatments for myopia and high myopia focus on correcting the refractive error. Typically, this is done using prescription eyeglasses or contact lenses. There are also other types of treatment for myopia, some of which help slow the progression of nearsightedness.
With refractive surgery, the eye doctor uses a laser to reshape the cornea. This makes the light bend, or refract, properly to reach the retina.
Common types of refractive surgery for myopia are:
- refractive lens exchange
Slowing the progression of myopia
Slowing myopia in children may help prevent high myopia and its complications. The following treatments can help slow the progression of nearsightedness in children:
- Orthokeratology (Ortho-K): This treatment involves sleeping with hard contact lenses in order to flatten the cornea. The drawback to this procedure is that the effects last only as long as the person wears the hard contact lenses. When the contacts are no longer worn while sleeping, the cornea returns to its initial form.
- Multifocal soft contact lenses: These lenses combine several refractive prescriptions into one lens and have been shown to slow the progression of myopia.
- Dual-focus contact lenses: These lenses can also slow the progression of nearsightedness in children. The brand, MiSight, was the first Food and Drug Administration (FDA)-approved product of its kind. The 1-day disposable lenses correct the current refractive error while also redirecting how light enters the retina, which signals the eye to slow its growth.
- Low dose atropine: In eye care, doctors use atropine to dilate the pupils. This helps them see the retina at the back of the eye. For myopia, low dose atropine eye drops can slow myopia progression in children ages 6–12 years. This is based on numerous clinical trials in many countries, including a large 5-year clinical trial in Asia and a 2019 study in the U.S.
What happens if you do not treat myopia?
Untreated myopia could progress to high myopia, which increases the chance of eye problems such as developing cataracts or glaucoma or having a retina tear or detach.
High myopia also carries an increased chance of blindness.
You cannot change your genetic predisposition for developing myopia, but you may be able to slow the progression or severity of myopia by:
- using appropriate lighting for reading and other activities
- increasing time spent outdoors, which is associated with a lower incidence of myopia
- reducing screen time
- treating the condition with specialty contact lenses, such as MiSight and Ortho-K
There is considerable interest in low dose atropine eye drops as a method of slowing the progression of myopia in children. The goal of so-called myopic control is to slow myopic growth during the most active years of eye growth. By managing myopia, you may help prevent high myopia and its potential complications, such as glaucoma.
The FDA has not approved the use of low dose atropine for myopic control in children. However, some eye doctors may prescribe atropine off-label.
Myopia, or nearsightedness, is when you can focus clearly on items near you but not on items far away. This typically occurs because of an irregularly shaped cornea or lens. As a result, light cannot properly reach the retina to focus it correctly on objects. The farther away the object, the blurrier it is.
Treatment options include prescription eyeglasses or contact lenses, refractive surgery, and nonsurgical solutions, such as MiSight or Ortho-K. Low dose atropine can slow the progression of myopia in children and prevent high myopia, which can lead to serious eye problems.