What is astigmatism?
Astigmatism may sound scary, and is often confused as an eye disease, but it is simply a type of refractive error that causes blurry or distorted vision at all ranges. Astigmatism may occur on its own or may be present in conjunction with other refractive errors, such as myopia (nearsightedness) or hyperopia (farsightedness).
“Normal” vision, or seeing clearly without corrective lenses, requires light to focus directly on the retinal tissue in the back of your eye. In astigmatic eyes, either the cornea or the lens (or both) are irregularly shaped, which causes light to scatter onto multiple points on the retina. This creates multiple images which can overlap or combine, resulting in blurry or distorted vision.
You may hear astigmatism be described as the eye being “shaped like a football.” This is simply a way of explaining that the ocular surface is not as round and smooth as it should be, and one of the two corneal axes is steeper than the other, creating an elongated shape.
Who develops astigmatism?
Astigmatism can be present at birth or may develop over time. A 2018 study showed that globally, 1 in 10 children or teenagers and 4 in 10 adults have astigmatism.
It is unknown why astigmatism develops, however, there is a strong genetic component that indicates a 50% increased risk of developing astigmatism when one parent or one sibling has it. In addition to natural occurrence, astigmatism may also occur as a result of an eye injury, disease or surgery.
What are the symptoms of astigmatism?
Low levels of astigmatism may go undetected until discovered during a comprehensive eye exam. Patients with higher levels of astigmatism may experience the following symptoms:
- Blurry or distorted vision that is noticed both far away and at near
- Double vision (or a shadow type effect when looking at letters)
- Squinting in order to see clearly
- Headaches or eye strain, especially after reading (some children may not be able to verbalize this feeling but it may be noticed as rubbing their eyes, short attention span, or excessive blinking)
- Difficulty with nighttime vision (blurred vision, glare, halos/starburst appearance)
How do you treat astigmatism?
Astigmatism is most commonly treated with glasses or contact lenses, but surgical correction is also available for certain levels of astigmatism.
Contact lens companies are frequently developing new contact lens parameters to accommodate more patients and prescriptions. If you were told in the past that you could not wear contact lenses due to your astigmatism, it may still be worthwhile to ask our doctors if you might be a candidate now.
If you suspect that you or your child may be struggling with undiagnosed astigmatism, please contact our office or schedule an eye exam online! Our doctors can discuss your best treatment options at your visit!