What is astigmatism??
Question: well yesterday i got an eye exam. and well i've been using contact lenses for a year now but this time when i went to get my eye exam they told me that i had astigmatism and i have to use a different, a lil more expensive kind of contact lenses. so i just want to know what astigmatism is. thanx. :)
Answers: Speaking from experience here...it means you can't see very well! LOL
When you have an astigmatism, your corneas are mishapen causing different light rays that hit different points on your cornea to hit your retina at different points, which causes blurry vision. Think of light as little beams that go into your eye and are bent by your corneas. Then they hit your retina and are sent to your brain. If your cornea does its job, then the rays will be bent correctly and hit your retina on the appropriate place. When it doesn't your vision is blurry.
Astigmatism Symptoms and Signs
If you have only a small amount of astigmatism, you may not notice it or have just slightly blurred vision. But sometimes uncorrected astigmatism can give you headaches or eyestrain, and distort or blur your vision at all distances.
It's not only adults who can be astigmatic. Dr. Karla Zadnik, an optometrist at Ohio State University School of Optometry, found in a recent study of 2,523 children that more than 28 percent of them had astigmatism. Children may be even more unaware of the condition than adults, and they are unlikely to complain of the blurred or distorted vision. Unfortunately, astigmatism can affect their ability to see well in school and during sports, so it's important to have their eyes examined at regular intervals in order to detect any astigmatism early on
Astigmatism in most cases refers to the shape of the cornea (the clear part in the front of the eye). The cornea is usually round like a baseball. People with astigmatism have corneas that are shaped more like a football, or the back of a spoon. That is, the surface is more curved along one axis, and relatively flatter along the perpendicular axis.
This more expensive contact lens you refer to is a toric lens. People with up to about 1.00-1.50 diopters of astigmatism can usually get away with not using toric lenses. A small adjustment of the presription has to be made. I don't know your prescription but if you fall in this range you may still be able to use a spherical lens. You'll have to try a trial pair on at the optometrist's and see how your vision is. Ask if you can use the spherical equivalent .
Your eyes can't see as sharply because the cornea (i think, not sure, i know it begins with a c ) is slightly misshaped. I have it in my left eye and so my glasses have two differently powered lenses. no big deal, I just sometimes get headaches when I try to see without my glasses.
The lens of the eye should be smooth and even. When you have astigmatism the lens has lost the perfect shape and becomes slightly irregular. While your existing lenses might be perfect for many areas of the eye, it cannot correct for near or far sightedness in other areas.
Nothing to worry about and unless you experience poor accuity, there is not much reason to change.anything.
You only use the absolute center of the lens to see objects. Everything else around it is not really important. Try looking at a wall - What do you really see? Only the part of the wall that you are specifically looking at. The area all around that can be seen but it is not a Focal Point .
You make the decision. If normal vision is sharp, no need to worry. If it is alightly blurry then change to the new special lenses. But - contacts do not stay in the same place at all times. How can you have carrective lenses that rotate and moce slightly over the cornea?
Hmm?
its an uneveness of the eyes cornia...the contacts are just like weighted a little bit diff to compensate, no big deal...i have it too
http://en.wikipedia.org/wiki/Astigmatism
get reading!
All good answers above. I''l add a caution I've been given a couple of times by my eye doctors since I hit age 40. Those with astigmatism and over 40 are in a higher risk group for detached retina if you go on some rides at parks that involve high acceleration/deceleration. Like the ones that drop you down the side of a tower, or, at Disney World, Tower of Terror (my favourite).
Answers: Speaking from experience here...it means you can't see very well! LOL
When you have an astigmatism, your corneas are mishapen causing different light rays that hit different points on your cornea to hit your retina at different points, which causes blurry vision. Think of light as little beams that go into your eye and are bent by your corneas. Then they hit your retina and are sent to your brain. If your cornea does its job, then the rays will be bent correctly and hit your retina on the appropriate place. When it doesn't your vision is blurry.
Astigmatism Symptoms and Signs
If you have only a small amount of astigmatism, you may not notice it or have just slightly blurred vision. But sometimes uncorrected astigmatism can give you headaches or eyestrain, and distort or blur your vision at all distances.
It's not only adults who can be astigmatic. Dr. Karla Zadnik, an optometrist at Ohio State University School of Optometry, found in a recent study of 2,523 children that more than 28 percent of them had astigmatism. Children may be even more unaware of the condition than adults, and they are unlikely to complain of the blurred or distorted vision. Unfortunately, astigmatism can affect their ability to see well in school and during sports, so it's important to have their eyes examined at regular intervals in order to detect any astigmatism early on
Astigmatism in most cases refers to the shape of the cornea (the clear part in the front of the eye). The cornea is usually round like a baseball. People with astigmatism have corneas that are shaped more like a football, or the back of a spoon. That is, the surface is more curved along one axis, and relatively flatter along the perpendicular axis.
This more expensive contact lens you refer to is a toric lens. People with up to about 1.00-1.50 diopters of astigmatism can usually get away with not using toric lenses. A small adjustment of the presription has to be made. I don't know your prescription but if you fall in this range you may still be able to use a spherical lens. You'll have to try a trial pair on at the optometrist's and see how your vision is. Ask if you can use the spherical equivalent .
Your eyes can't see as sharply because the cornea (i think, not sure, i know it begins with a c ) is slightly misshaped. I have it in my left eye and so my glasses have two differently powered lenses. no big deal, I just sometimes get headaches when I try to see without my glasses.
The lens of the eye should be smooth and even. When you have astigmatism the lens has lost the perfect shape and becomes slightly irregular. While your existing lenses might be perfect for many areas of the eye, it cannot correct for near or far sightedness in other areas.
Nothing to worry about and unless you experience poor accuity, there is not much reason to change.anything.
You only use the absolute center of the lens to see objects. Everything else around it is not really important. Try looking at a wall - What do you really see? Only the part of the wall that you are specifically looking at. The area all around that can be seen but it is not a Focal Point .
You make the decision. If normal vision is sharp, no need to worry. If it is alightly blurry then change to the new special lenses. But - contacts do not stay in the same place at all times. How can you have carrective lenses that rotate and moce slightly over the cornea?
Hmm?
its an uneveness of the eyes cornia...the contacts are just like weighted a little bit diff to compensate, no big deal...i have it too
http://en.wikipedia.org/wiki/Astigmatism
get reading!
All good answers above. I''l add a caution I've been given a couple of times by my eye doctors since I hit age 40. Those with astigmatism and over 40 are in a higher risk group for detached retina if you go on some rides at parks that involve high acceleration/deceleration. Like the ones that drop you down the side of a tower, or, at Disney World, Tower of Terror (my favourite).
More questions & answers:
- Does astigmatism come and go?
- Astigmatism, will it matter?
- What is astigmatism?
- LASIK okay for astigmatism?
- Do I have astigmatism?
- About how long does astigmatism last?
- How bad is 'bad astigmatism'?
- Is it optional to get the astigmatism contacts if i have astigmatism,or do i have 2 use that special contacts?
- Colored contacts for astigmatism?
- Can you wear colored (nonperscription) contacts if you have an astigmatism?
- What's the best colored contacts for an astigmatism?
- Is it possible to check astigmatism prescription by lenses?