Can I Have Astigmatism in Both Eyes?

Astigmatism almost always occurs in both eyes. The condition can occur in only one eye, but that is usually the result of a physical injury.

What to Know About Astigmatism - Illustration by Theresa Chiechi

Verywell / Theresa Chiechi

What Is Astigmatism?

Astigmatism is a fancy word that is used to describe a malfunction of the way vision works. Astigmatism is a common disorder of the eyes that can cause light to focus on two points instead of just one. This condition can be the result of a misshapen cornea. Astigmatism causes people to have blurry, slanted or distorted vision.

Astigmatism is a refractive error because it affects how the eye refracts, or bends light.

It is a vision disorder in which the eye focuses light on the retina at two points instead of just one. People with astigmatism sometimes complain of blurred, distorted, slanted, or double vision. Astigmatism almost always occurs in both eyes and is usually quite symmetrical between the two. Astigmatism in large amounts is often inherited. Astigmatism can occur in one eye but this is most often due to a traumatic injury.

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Causes of Astigmatism

Astigmatism is sometimes caused by an irregularly shaped cornea, the clear dome-like structure on the front part of the eye. The cornea may have areas that are flatter or steeper than others, resulting in distorted vision. The crystalline lens inside the eye may also be tilted slightly, causing astigmatism.

In addition, astigmatism can be caused by an irregular eyelid or heavy tissue pressing down on the eye.

Astigmatism is very common and usually treated or corrected by wearing glasses or contact lenses. Refractive surgery such as LASIK or astigmatic keratectomy can also be helpful in treating astigmatism.

Symptoms of Astigmatism

Astigmatism, if left untreated, can cause distressing vision problems. If you have astigmatism, you may have symptoms that alert you or your healthcare provider. Some symptoms of astigmatism may occur alone, but others might occur together.

If you notice any of the following symptoms, make an appointment with your eye care specialist as soon as possible. (It is generally recommended to have a comprehensive eye exam once per year to ensure the best possible vision as well as prevent or uncover eye disease.)

  • Blurry or distorted vision
  • Eye fatigue
  • Eyestrain
  • Headaches
  • Inability to read small print
  • Constant squinting of the eyes

When there is astigmatism in both eyes it usually isn't the same amount. This may cause or increase eye strain and contribute to headaches.

The irregular curvature of the eye leads to blurry or distorted vision for all distances and not just for things close up or far away. Astigmatism can also increase glare around lights at night in a more pronounced way than for those with normal vision. For example, people with astigmatism may say that they see halos or lines from street lights and car lights when driving at night.

Astigmatism is common in children, though they may not complain about blurry or distorted vision. They may struggle in school or even be misdiagnosed as having a learning disability when the issue is really related to their vision. Regular eye exams are a way to detect astigmatism or other vision problems in children and adolescents.

Diagnosing and Treating Astigmatism

Your eye doctor may diagnose astigmatism by conducting a variety of tests. Some of the tests used to diagnose astigmatism include a simple vision test, light refraction test, cornea measurement, or electronically mapping the surface of the eye. 

Astigmatism is corrected by focusing light rays on a single plane. This can be accomplished by prescribing eyeglasses or contacts or be performing astigmatic keratotomy.

Frequently Asked Questions

  • How common is astigmatism in both eyes?

    About 40% of adults have astigmatism and most cases are in both eyes.

  • Can a child develop astigmatism in adolescence?

    It is often present at birth but astigmatism can increase or decrease over time, so symptoms may develop or become more pronounced during adolescence. There is also a rare eye disorder called keratoconus that typically begins during puberty and causes thinning and changes in shape of the cornea that can lead to astigmatism.

  • What other eye issues are common with astigmatism?

    Other refractive errors, or those that affect how the eye bends light, are common. Astigmatism commonly occurs along with myopia (nearsightedness, or things in the distance look blurry) or hyperopia (farsightedness, or close objects look out of focus).

  • Can I go blind from astigmatism?

    Astigmatism can blur or distort vision, but it does not cause blindness.

  • Why is astigmatism worse at night?

    The pupils of your eye dilate to let in more light and this can contribute to glare and seeing halos around lights.

  • Can astigmatism lead to lazy eye?

    If the astigmatism is in just one eye, it can cause lazy eye, particularly if the astigmatism goes untreated.

  • Can Lasik correct astigmatism?

    If the astigmatism is mild to moderate, Lasik can correct vision in most cases. For more severe astigmatism, the procedure is less reliable.

  • Can astigmatism be cured naturally?

    Astigmatism is a structural issue with the curvature of the cornea or lens. There aren't natural treatments that will change the structure of your eye.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Eye Institute. Astigmatism.

  2. American Academy of Ophthalmology. If you have astigmatism in one eye do you always have it in the other eye?

  3. American Optometric Association. Astigmatism.

  4. American Academy of Ophthalmology. What is astigmatism? Symptoms, causes, diagnosis, treatment.

  5. Hashemi H, Fotouhi A, Yekta A, Pakzad R, Ostadimoghaddam H, Khabazkhoob M. Global and regional estimates of prevalence of refractive errors: Systematic review and meta-analysis. Journal of Current Ophthalmology. 2018;30(1):3-22. doi:10.1016/j.joco.2017.08.009

  6. National Organization for Rare Disorders. Keratoconus.

  7. Centers for Disease Control and Prevention. Uncorrected refractive error.

  8. National Eye Institute. Amblyopia (lazy eye).

  9. American Academy of Ophthalmology. LASIK for myopia and astigmatism: safety and efficacy.

By Troy Bedinghaus, OD
Troy L. Bedinghaus, OD, board-certified optometric physician, owns Lakewood Family Eye Care in Florida. He is an active member of the American Optometric Association.