Astigmatism is a very common eye condition that is present in about one out of three people, but many people don’t know a lot of specifics about it and what it means to have it. Many people have some degree of Astigmatism. For some, it is so slight they don’t require treatment. However, for others, it may cause distorted or blurred vision, eye discomfort or headaches.
Astigmatism is usually caused by an irregularly shaped cornea, which is the clear covering over the iris, pupil, and lens. Our corneas are supposed to be symmetrically round, like a basketball, but in some people it is shaped more like a football. In the people with the irregularly shaped corneas, one meridian is significantly more curved than the meridian perpendicular to it. A meridian is a line that bisects a circle, or a curve that bisects a sphere (like an eyeball), either vertically or horizontally. The deformities in the curves are what cause blurred/distorted vision.
The 3 primary types of astigmatism are:
- Myopic astigmatism – One or both meridians of the eye are nearsighted.
- Hyperopic astigmatism – One or both meridians of the eye are farsighted.
- Mixed astigmatism – One meridian is nearsighted and the other is farsighted.
Astigmatism is usually present from birth, but can change from childhood to adulthood and either decrease or worsen with time. A comprehensive eye exam will include testing for Astigmatism and is one of the many reasons to have an exam done regularly. A refraction test can help detect Astigmatism by seeing how the direction of light is changed as it passes through your cornea. Astigmatism can be easily treated with glasses, contacts or laser eye surgery.
If you’re finding your vision to be a bit blurred or are having frequent headaches, it’s time to schedule your next exam. You can do that by clicking here.