There are some common terms that you may hear during your visit to your optometrist and one of them may be the word “astigmatism”. This is because an astigmatism is a very common eye condition, which tends to occur in everybody to a certain amount. Most amounts of astigmatism can be corrected by either eyeglasses, contact lenses, and in many cases even eye surgery. But for many people who have an astigmatism, they don’t know what it is, why they have it, or what the options are for astigmatism correction.
What Is An Astigmatism?
An astigmatism is a commonly misunderstood vision problem. Although the term may sound serious, it is a common, fairly easily correctable eye problem. Astigmatism occurs because of an error in the shape of the eye and how the it focuses light within the eye. Many people know that they have an astigmatism, but they don’t actually know what it is, or their options for astigmatism correction. Naturally, an eye should be shaped like a round ball or a sphere. When light enters an eye which is shaped like a ball or sphere, light is focused evenly in one sharp point. If that point ends up on the back of the retina, it results in a clear image being sent to the brain. In a person’s eye who has an astigmatism, the eye is more oval shaped like a football or egg. When light goes into the eyes of a person with an astigmatism, it is refracted or bent in different directions then others. Because light is focusing in multiple points, it causes only part of the object to be in focus. For many individuals with astigmatism, their vision may be interpreted as being blurry or wavy.
What Causes An Astigmatism?
A person may have an astigmatism for many different reasons. The most common reason a person has an astigmatism results from the shape of the cornea (clear dome over the pupil) of the eyes, not being perfectly spherical or round, this is called corneal astigmatism. In other cases, astigmatism is caused because of the shape of the crystalline lens (lens behind the pupil) within the eyes, is not completely spherical, this is referred to as lenticular astigmatism. Astigmatism can also result for other reasons such as eye injury, from eye surgery, or from corneal eye diseases, such as keratoconus. Dependent on the type and amount of astigmatism, different recommendations for astigmatism correction may be made.
How To Tell If You Have An Astigmatism
Generally, an astigmatism is diagnosed by your optometrist during your eye exam. At the time of your eye exam, your optometrist will usually tell you if you are farsighted, nearsighted, or have an astigmatism. You can have a combination of astigmatism with being far sighted or nearsighted. An astigmatism is written in your eyeglass prescription in the “cylinder” and “axis” components. These numbers correspond to each other to let your optician know where the astigmatism is within the eyes, as well as how much arount of astigmatism you may have. Because the amount of astigmatism as well as where the astigmatism aligns within the eyes can change over time, it is important to have routine eye exams, or an exam sooner, if you notice a change in your vision.
Once your optometrist determines if you have an astigmatism, they will suggest the best method for astigmatism correction. There are a few different ways to correct astigmatism, such as eyeglasses, contact lenses, and even refractive surgery. Discuss with your eye doctor or optician which is the best option for you!
Article Written By: Trina Vanaalst