What is Astigmatism?

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Astigmatism is a condition of the human eye which causes either blurred vision or a sense that each eye is seeing objects slightly differently. Sometimes astigmatism can be detected by an individual if he covers one eye to look at an object, and then changes to cover the other eye. By switching back and forth between covering each eye while looking at the single object or in one direction, it will become apparent with astigmatism that the object seems to move, as though each eye is seeing it in a slightly different location.

Astigmatism is not a vision problem, but a structural problem with the eye. The human eye is usually shaped in a sphere, like a ball, but with astigmatism, the cornea of the eye is curved instead into an oval shape, more like a football. When the eye is not curved properly, or has uneven curves like a football, light will not travel in and out of the eye normally. Astigmatism causes light to bounce unevenly off the flat and steep curves of the oval shaped eye, thus allowing light to more than one point in the eye. This impairs focusing ability, causing blurred vision.

There are several ophthalmological tests to determine the presence and level of astigmatism. A keratometer and a corneal topographer measure the curvature of the cornea. An autorefractor can give an estimate of the eye's ability to focus light properly. Most ophthalmologists and optometrists are able to detect even slight cases of astigmatism with just a simple eye exam.

Glasses or contact lenses can be presecribed to treat astigmatism, but they generally do not correct the condition. Often, two different lenses will help the eyes focus together, thus offsetting the uneven focusing caused by astigmatism. Astigmatism, however, can be corrected with surgery. Lasik and astigmatic keratotomy are two commonly used surgeries for astigmatism. The object of surgery is to reshape the cornea of the eye and make it more spherical.

Astigmatism is quite common, with thirty percent of the population having some level of cornea curvature. Often, mild astigmatism goes largely unnoticed, but severe astigmatism may cause, in addition to blurred vision, headaches, squinting and fatigue. Most people with astigmatism are born with it, but the awareness of it increases with age.

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16
I am a teacher and am often glancing over students' shoulders as they write or take notes or a test. I can't read anything they have on their papers and they get very frustrated when I often stop them and ask to see their papers.

When I drive at night I am petrified! The headlights coming at me seem to be everywhere and blinding me. I have not driven at night since I was 28 years old.

I am 31 and was told I had astigmatism in both eyes it was moderate but since it was the first time I had been to the eye doctor and had never worn glasses they gave me a lesser prescription than I really needed.

They give me a headache and I hate wearing them. I have a student who also hates his glasses and won't wear them so I now wear them during his class.

I will suffer for him!

- anon60211
15
i have astigmatism and i wear glasses. i hope they can cure it before it gets worse.
- anon60197
14
I was required to wear eyeglasses when I was 10 because I've been having bad headaches and the doc said I have astigmatism. But I don't wear glasses anymore right now.

I am just wondering if this is a sign of astigmatism like I can control my eyesight to get blurry and make it very bad and then back to normal but it doesn't hurt my eyes.

I learned to do this since childhood till now. I have told my parents about this but they can't relate and forgot to ask about this to my past doctors. Or is it just normal?

- anon58235
13
i discovered i had astigmatism just a few years ago (i am 31 now). it is in my right eye and moderate. i wear a special contact in my one eye, but my vision often seems "misaligned" (other times, it is not really a bother)because one eye seems to overpower the other.

i haven't had serious problems, but I'm beginning to seriously consider LASIK surgery, as i anticipate the problem getting worse. my advice to anyone with vision problems is make sure you see a qualified ophthalmologist, they will help you diagnose your problem accurately.

- anon55931
12
I suspected that i might have astigmatism when I started to read a financial statement and thought that the lines where misaligned.

So I drew two lines with a ruler with a half inch gap in between and stared at them. To me, the lines looked like they were misaligned. I showed it to my roommate and he didn't see a problem. The eye doctors never caught it when I was a kid. Too bad, I could have been a star athlete but my hand-eye coordination was always off. Now I know why.

- anon55220
11
I have a reading glass which was issued me by an opthamologist couple of years ago. Now I have been diagnosed of astigmatism. Please where are my eyes heading to? I want to know. Can I cope with two eye glasses for the two defects? My head aches, my vision is blurred and I cannot grasp an object easily. Thank you for this medium.
- anon48054
10
I thought it was normal to see things jump when you close one eye at a time.I used to have this magic book that said that if you could do that, it was a trick to show all your friends or something. but now i have a bit of astigmatism! Stupid magic book.
- anon41652
9
I have just been diagnosed with mild astigmatism and found this page so helpful - thanks! My last optometrist was really rude to me when i said that sometimes i can't read things close up or from a distance. She obviously hadn't picked up on the fact that i don't have problems with eye sight, just fine details! Was so relieved when i got a second opinion - proof i wasn't going nuts! My left eye is 'zoomed out' while my right eye is 'zoomed in' and i have since noticed that i tilt my head a lot, and i have read that people with this condition can see walls tilting - does anyone else notice this?
- anon41370
8
i have mild astigmatism, and i have a pair of glasses, one lens "normal", the other slightly different.
- anon40298
7
I didn't know what astigmatism was or what caused it. I only knew it was blurry vision & headaches. You mention that with the years it increases with age. I was told I have astigmatism at the age of 15 now and 26. My optometrist told me that it will not advance. Is it true? Or as I get older my vision will be very poor? Thanks Nay
- anon37175
6
im using air optix contact lenses and these dont seem to treat it. are there special contacts that will help to treat it?
- anon36922
5
Thanks heaps for this page. I have very poor vision (short sighted) so I've been wearing glasses for a few years now, and even though my optometrist told me I have astigmatism on top of that, I've never been too sure what astigmatism was apart from blurry vision.

My astigmatism has worsened, but I've only been short sighted until I was about 13, so this explains why I have memories from when I was only six of objects jumping from different positions when I covered one eye (something which I thought happened to everyone) but my parents could never relate. It also explains why now I've noticed a considerable difference in colours from either of my eyes - I never knew these were symptoms.

Thanks again, I'll be sure to browse your site at my next chance.

-Mary

- anon34077
4
Yes lolamom that is a symptom of it. Astigmatism increase with age and if untreated they get worse.
- anon33556
3
actually, i astigmatism in my left eye and i can use acuvue2 lenses that only cost 22usd a box. that is for me a 6 month supply.
- anon22630
2
Hi there,

I have an astigmatism in my left eye, and I have a very slight colour change in either eye, its unnoticeable unless I really concentrate on the colour of something and cover each eye individually, etc. My point is, I think astigmatisms can affect the eyes in many ways, not just blurry vision, but colour change, and as you say, focusing and zoom problems. I'd ask your optician about it if I were you. You'd need a high prescription for astigmatism so its really important you get it checked out, as not having the correct prescription can damage your eyes and make them worse. Some people use contact lenses as this gives them better vision than glasses, but I warn you now, if it is an astigmatism, you'll get Toric contact lenses, which are considerably more expensive than normal lenses. I'm paying £240 a year, and I only get 2 pairs of contacts a year (£50 to replace ONE lens if i lose it). Thats not including the £100 I paid for my specs!

goodness eye care is an expensive thing!

Anyway, hope this helps! :D

- lucychandler
1
can a symptom of astigmatism be when you cover one eye the object looks zoomed in on and when you cover the other eye the object looks like you zoomed out so with one eye covered the picture looked really big and when i covered the other eye the picture was smaller. I am wondering because I have glasses and the doc. said my eyes needed strengthened and they don't help at all i have very blurry vision and it's cause it takes me awhile to focus on stuff can you give me an opinion please?
- lolamom

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Written by Paulla Estes
Last Modified: 12 January 2010

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