The Back of a Spoon

Hypnoteyes · #1 (**permalink**) 06-17-2008, 11:48 AM

When trying to explain what astigmatism is, many people say that it's due to the cornea being shaped more like a football than a baseball.
Then I read the description that said that an astigmatic cornea is shaped like the back of a spoon.
Do we have any experts here that can agree with that analogy?

guru · #2 (**permalink**) 07-07-2008, 01:14 PM

I don't know too much about astigmatism.

Hypnoteyes · #3 (**permalink**) 10-08-2009, 12:09 PM

Quote:

Originally Posted by guru

I don't know too much about astigmatism.

Okay . . . thanks for playing. I'm afraid I don't have any lovely parting gifts for you.

Okay, is there anyone out there who DOES know about astigmatism and can tell me about this spoon thing?

#4 (**permalink**) 10-08-2009, 12:31 PM

Quote:

Originally Posted by Hypnoteyes

When trying to explain what astigmatism is, many people say that it's due to the cornea being shaped more like a football than a baseball.
Then I read the description that said that an astigmatic cornea is shaped like the back of a spoon.
Do we have any experts here that can agree with that analogy?

I am by no means an expert on astigmatism (although I am proported to have a slight case of it), but, I did post this test somewhere here on the board yesterday. It's fairly self-explanatory.

Quote:

If you want to know whether you have astigmatism, try taking this test. Then see your O.D. to confirm it.

The Astigmatism test
What is it?
An astigmatism chart helps determine whether the curvature of your cornea or lens is normal. An abnormal curvature, usually more football-shaped than round, will sharply focus some portions of an image onto the retina while blurring others.

How do I do it?
1.If you have contacts or glasses, wear them.
2.Sit about 14 inches away from your computer screen.
3.Cover one eye.
4.Note how the lines and squares appear (for example, wavy or blurred).
5.Test the other eye in the same manner.

What do my results mean?
To a normal eye, the lines will appear sharply focused and equally dark. If some sets of lines appear sharply focused and dark while others are blurred and less dark, you may have astigmatism. Regardless of your result, see your eye doctor on a regular basis for a complete eye exam.

dragongirl81 · #5 (**permalink**) 10-08-2009, 01:42 PM

Hmmm . . .

According to my last check up in May, I do have astigmatism, but when I look at the test pattern with one eye covered, the lines look fine. I must be doing something wrong. Do you have a demonstration of what a person with astigmatism would see? Maybe I'm just not seeing what I'm seeing.

Now I'm starting to sound like Yogi Berra. "When you get to a fork in the road, take it."

Hypnoteyes · #6 (**permalink**) 10-22-2009, 03:21 PM

Quote:

Originally Posted by dragongirl81

Hmmm . . .

According to my last check up in May, I do have astigmatism, but when I look at the test pattern with one eye covered, the lines look fine. I must be doing something wrong. Do you have a demonstration of what a person with astigmatism would see? Maybe I'm just not seeing what I'm seeing.

Now I'm starting to sound like Yogi Berra. "When you get to a fork in the road, take it."

"Fork in the road." I get it!

Anyway, here's a picture of that test pattern that has been "fudged" (in the words of the website) to show what what a person with astigmatism would see.

This site also defines astigmatism in a unique way: "Astigmatism occurs when the surface of the cornea or of the lens is not perfectly smooth. If, for example, there is a small flat spot on your cornea the image in a certain direction on your retina will not be in perfect focus."