What causes astigmatisms?

I have to go to the eye doctor very soon because my vision is getting a little blurry. My friend tells me that I may have an astigmatism.

I would like to know what causes astigmatisms? Was it something that I did? I have allergies so I tend to have itchy red eyes and I rub them a lot. Is that how I got an astigmatism (or whatever it might be)?


Most Helpful Guy

  • An astigmatism occurs when the surface of the cornea (the lens in your eye which covers the pupil and filters light rays into your eye) is not spherical. This means it will refract the light rays differently than a normal, spherical eye. You may notice that you have trouble seeing horizontal lines and vertical lines at the same time. This is because of the deformation of your cornea, as the vertical spherical plane is offset from the horizontal spherical plane.

    Sorry if that was a bit confusing, I'm a physics major and we're studying light. The eye happens to be a incredible optical device, but when it's malformed it can cause difficulties with sight.

    It's unlikely that you yourself caused your astigmatism, although it is possible. If you were to rub your eyes hard enough to bend the cornea you could induce an astigmatism. I would suggest not rubbing your eyes so much, even if they do itch (sorry about that, I have allergies too and they suck).

    If you do have an astigmatism, whatever the cause, you will need to have some sort of vision correction in order to see properly. This means glasses, contacts, or laser surgery. (I can give you a run-down of how the glasses will correct your vision, too, if you'd like to hear it :P)

    • I don't rub my eyes very hard but I tend to rub them a lot. Should I use eye drops for itchy eyes?

      Sometimes 6's look like 8's if I'm looking at them from a far distance or if they're not bold enough.

      Yes, tell me how the glasses will correct my vision, and could you please tell me what the doctor will do to my eyes? I'm afraid they're going to poke me in the eyes or something T_T

    • If your cornea is malformed, it's probably in only one direction/plane (vertical/horizontal/etc). The glasses/contacts will then be curved in such a way as to not affect the light that you can see and to refract the light that your cornea is unable to refract properly. The doctor will test your eyes with a variety of lenses in order to determine how your eyes are actually shaped. From that, any conditions can be diagnosed. I don't think they'll poke you, that would just be rude :P haha

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What Guys Said 1

  • an astigmatism just means that your eyeball isn't round so light doesn't focus on your retina like it should. There is nothing that you did to cause it, so don't worry about that. If yours is the type were your eye is squished from the top to the bottom (as opposed to squished from side to side) your it'll tend to reverse itself as you get older and your vision can better. I have astigmatism and that's what my eye doctor told me.


What Girls Said 1

  • I'm pretty sure that's what I have too; I just got glasses recently because I couldn't see the street signs very well when I was driving. I would venture to say that it's genetic, because my dad has the same thing. I tend to have the same problems as him haha.

    When I went for the eye exam, they didn't poke at my eyes or anything. They did this one thing where they blow air into your eye, which is really awkward lol, but not painful or anything. Then just the regular thing where you read the letters, and they have you look through different lenses to see which one helps you see best. It's really no big deal. :]