
08/01/2025
Hi Everyone! Did you know that of the three numbers on your contacts or glasses prescription, the last two refer to astigmatism:
Spherical indicates whether you are nearsighted or farsighted. A plus sign indicates you are farsighted, a minus sign indicates you are nearsighted. The higher the number, the stronger your prescription.
Cylinder measures what degree of astigmatism you have, or how flat or irregular the shape of your cornea is. The more your eye looks like a football (instead of a basketball), the more astigmatism you have.
Axis is measured in degrees, and refers to where on the cornea the astigmatism is located. Axis numbers go from 0 to 180. If you think of the eye as a map hanging on a wall, the 90 degree axis or line, runs up and down (or north to south) on the eye. The 180 degree line runs across the eye, east to west.