When your eyes are exactly round, they can focus light evenly and clearly. With astigmatism, the cornea is slightly misshaped. This results in blurry vision because the light is unable to bend the way it should when it enters your eye. Research suggests that those with astigmatism are typically born with it or get it due to any eye injury. No one knows for certain what causes it. To determine if you have astigmatism, you will need to arrange an eye exam with your eye care professional. During this exam, a series of tests will be conducted to determine if you have astigmatism and the overall health of your eye.
Your doctor may choose to use one or more of these tests to ascertain if you have astigmatism and decide the severity of your specific situation.
- Vision test: This test involves reading letters, symbols, or numbers from a chart 20 feet away. If you are capable of reading from 20 feet what a normal eye can read from 20feet, your vision is 20/20. If you need to be 20 feet away to read what a normal eye can see from 80 feet away, you have 20/80 vision.
- Refraction: This test uses a lens machine called a phoropter. Your doctor will have you look through it and tell him which lens choice allows you to see best. This is used to determine your prescription.
- Keratometry: This test is capable of measuring the bend of the center of your cornea by ascertaining the steepest and flattest curves. These measurements will reveal to your doctor how well your cornea can focus.
- Cornea topography: This test can generate the most detailed information about the shape of your cornea. The doctor will ask you to look at a specific object, during which the machine will gather thousands of little measurements.
Schedule an eye exam
If you have blurry vision and do not know the cause, schedule an eye exam with the Eye Institute.