Headshot of a man wearing glasses

At a glance: Astigmatism

  • Symptoms:

    Headaches, blurry vision, eye strain, trouble seeing at night

  • Diagnosis:

    Dilated eye exam

  • Treatment:

    Eyeglasses, contact lenses, surgery

What is astigmatism?

Astigmatism is a common eye problem that can make your vision blurry or distorted. It happens when your cornea (the clear front layer of your eye) or lens (an inner part of your eye that helps the eye focus) has a different shape than normal.

The only way to find out if you have astigmatism is to get an eye exam. Eyeglasses or contact lenses can help you see better — and some people can get surgery to fix their astigmatism.

What are the symptoms of astigmatism?

The most common symptoms of astigmatism are:

  • Blurry vision
  • Needing to squint to see clearly
  • Headaches
  • Eye strain
  • Trouble seeing at night

If you have mild astigmatism, you might not notice any symptoms. That’s why it’s important to get regular eye exams — your eye doctor can help you make sure you’re seeing as clearly as possible. This is especially true for children, who may be less likely to realize that their vision isn’t normal.

What causes astigmatism?

Astigmatism happens when your cornea or lens has a different shape than normal. The shape makes light bend differently as it enters your eye, causing a refractive error. 

Doctors don’t know what causes astigmatism, and there’s no way to prevent it. Some people are born with astigmatism, but many people develop it as children or young adults. Some people may also develop astigmatism after an eye injury or an eye surgery.

How will my eye doctor check for astigmatism?

Eye doctors can check for astigmatism as part of a dilated eye exam. The exam is simple and painless. 

What's the treatment for astigmatism?

The most common treatments for astigmatism are eyeglasses or contact lenses. Your eye doctor will prescribe the right lenses to help you see as clearly as possible.

Doctors can also use surgery to treat astigmatism. The surgery changes the shape of your cornea so that it can focus light correctly.

If your astigmatism is mild, you may not need treatment. Your eye doctor can help you figure out if you need to get treated, and what type of treatment is best for you.

Last updated: June 26, 2019