Ever wondered why you see beams of light coming from basically any lightbulb you come across? Well you, my friend, are likely part of the population with a very particular condition.
Whether its first thing in the morning or late at night, approximately one-third of Americans face being subject to symptoms including the need to squint to see clearly, headaches, trouble seeing at night and blurry vision.
It's this latter symptom which can might cause you to see beams spreading from a light source, just like the lights caught in this particular photo shared on Reddit:
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The image, shared on the subreddit r/InterestingAsF*ck, shows light emerging in straight lines from lights all over the room. It captures what some people would have likely seen while at the event, though not everyone.
Those who do see lights like this likely have a condition called astigmatism, which happens when when your cornea (the clear front layer on the eyeball), or your lens (inside your eye) has a different shape than normal.
While a normal eye is perfectly round, people with astigmatism have egg or oval-shaped eyes, like a football - an American one.
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A mild astigmatism likely won't result in any symptoms, but the abnormal shape of the lens or cornea caused by the condition can make light bend as it enters your eye, causing a refractive error.
"I always thought this was normal," one person wrote on Reddit after seeing the photo. "Like when it rains at night I [would] look at the street lights and they would look like big red and green stars stretching further because of the [rain] drops on the windshield. Then I found out I have astigmatism, crazy to think not everyone sees the glare."
If this sounds like something you experience, you don't need to panic.
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Astigmatism is common, with some people born with the condition while others develop it after an eye injury, disease or surgery, the Mayo Clinic explains.
Doctors don't know why the shape of the lens or cornea can vary between people, but the risk of getting it is inherited from parents.
You can find out for certain if you have astigmatism by going to the opticians for an eye exam, where testing might include reading from an eye chart or looking through a device known as a 'phoropter', where you have to relay which letters you can see better.
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Tests can also include an autorefractor, where a light is shined into the eye, and a keratometer to measure the curve of your cornea.
If you do have the condition, your doctor can treat it with glasses or contact lenses, or even with surgery which changes the shape of your cornea.
However, if your astigmatism is mild, you probably won't need treatment.
Emily Brown