Astigmatism symptoms and signs: How does astigmatism affect vision?

Astigmatism is one of the most common types of refractive error, and its most obvious symptom is blurry vision at more than one distance. However, people who have very mild astigmatism might not experience noticeable vision problems. 

Symptoms of astigmatism include: 

• Blurry vision at multiple distances

• Distorted vision

• Double vision

• Poor depth perception

• Poor night vision

• Headaches and eye strain

• Squinting

Squinting and headaches are important signs to look for in young children, who might not realize their vision is blurred if they’ve never experienced clear vision. [Read more about squinting in children and teens.]

So how do you know if you have astigmatism? The only way to know for sure is to have a comprehensive eye exam. Understanding the symptoms and signs can help you talk to your eye doctor about why you suspect you or your child may have astigmatism.

Blurry vision at multiple distances

All refractive errors cause blurry vision, but not all of them cause blurry vision at more than one distance. For example, myopia (nearsightedness) blurs distant vision, and hyperopia (farsightedness) blurs near vision.

Astigmatism occurs when the eye’s cornea or natural lens has an asymmetrical shape. The asymmetry means that light entering the eye from different angles gets refracted (or bent) onto multiple focal points inside the eye instead of only one.

This is why astigmatism can affect near, intermediate and distance vision at the same time. Though vision is blurred at more than one distance, it’s common for one distance to be blurrier than another.

Distorted or double vision

Distorted or wavy vision is another problem that may be caused by astigmatism. The asymmetry in the shape of the cornea or lens can refract light in such a way that objects seem bent or warped, like how things look in a fun-house mirror. 

High degrees of astigmatism can also cause double vision, or seeing two images of one object. Objects may also look larger or smaller than they really are.

Poor depth perception

Vision distortion with astigmatism can also take the form of poor depth perception. This means it’s harder to judge how near or far away an object is. Vision distortion and poor depth perception can sometimes cause non-visual symptoms, such as dizziness or nausea.

Poor night vision

In dim lighting or darkness, the pupils automatically widen to let in more light. For eyes with evenly rounded corneas and lenses, the extra light improves vision. But if the cornea and lens are asymmetric, the widening of the pupil just increases the amount of uneven surface area the light passes through.

This can make blurring and depth-perception problems worse. It can also create halos and extra glare around lights. These symptoms can make it difficult or even unsafe to drive at night without corrective lenses.  

SEE RELATED: Astigmatism: Effects on light and night driving

Headaches and eye strain

People with very mild astigmatism might not ever notice any blurry vision, but that may be because the eye muscles that help with focus are working overtime. The result is eyes that feel tired, sore or strained, and eye strain can sometimes lead to headaches. Eye strain from uncorrected astigmatism can feel very similar to digital eye strain.

Squinting

Frequent or constant squinting can also be a sign of astigmatism or a factor in eye strain; it’s common for people to be unaware of how often they squint every day to improve focus.

Squinting, eye strain and headaches may also be signs that it’s time to have your glasses or contact lens prescription updated or checked for accuracy. Contact lenses for astigmatism are especially difficult to fit, and if they don’t sit properly on the eye, they won’t help vision as much as they should.

Astigmatism in children

Very young children who were born with astigmatism may squint throughout the day, whether they are reading, watching TV or playing outside. But even if they don’t squint, and they say they can see clearly, headaches or achy eyes could be signs of astigmatism.

Many children may experience these symptoms and not recognize or report them. In fact, they may not even know their vision is blurry until they have an opportunity to see through corrective lenses.

HAVE MORE QUESTIONS ABOUT ASTIGMATISM? Check out our Astigmatism FAQs.

Astigmatism treatment options

People with astigmatism have a wide range of treatment options. It is usually easy to correct with eyeglasses, contact lenses or laser vision surgery. There are also great lens and surgical options for people who have astigmatism and presbyopia or astigmatism and cataracts.  

If you’d like to learn even more about contact lenses for astigmatism, we have a lot of helpful information in this eye doctor Q&A.

For more information about laser surgery for astigmatism, our LASIK Surgeon Q&A and LASIK FAQs are great resources as well.

Page published on Monday, August 10, 2020