Astigmatism

Astigmatism is a common refractive error of the eye that causes blurred or distorted vision due to an irregular shape of the cornea.

Astigmatism can occur alongside other refractive errors like nearsightedness (myopia) or farsightedness (hyperopia). Normally, the cornea is smooth and evenly curved, allowing light to focus sharply on the retina. In someone with astigmatism, the cornea is shaped more like a football or an egg (oval), rather than being perfectly round, which prevents light from focusing properly on the retina and results in blurry or distorted vision. 

We measure Astigmatism at every comprehensive eye exam. We use a test called keratometry or corneal topography to measure the curvature of the cornea. Also, we can determine the degree of astigmatism during the refraction. 

Symptoms: 

• Blurry or distorted vision at all distances, but especially at near or far distances. 

• Eye strain or discomfort, particularly when reading, using a computer, or driving. 

• Headaches from prolonged visual strain. 

• Squinting to see clearly. 

• Double vision or halos around lights in some cases.  

Causes: 

• Genetics: If one or both parents have astigmatism, there’s a higher chance that their children will develop hyperopia.  

• Environmental: Rubbing the eyes can cause the cornea to loosen and bow out, which can make astigmatism worse. Worse for patients with systemic allergies.  

Treatment: 

• Glasses: Special lenses are prescribed to compensate for astigmatism and allow light to focus properly on the retina. 

• Contact lenses: Toric contact lenses are designed for people with astigmatism. They are shaped in a way that corrects the uneven curvature of the cornea. 

• Sclerals: Lenses that vault over the cornea from the white of the eye.  

• Refractive surgery: Procedures like LASIK or PRK can reshape the cornea to correct the irregular curvature and reduce or eliminate the need for glasses or contact lenses. 

*Hyperlink Contact lenses and Sclerals to Types of Contacts 

Masqueraders of Astigmatism: 

There are certain corneal dystrophies, such as Keratoconus and Pellucid Marginal Dystrophy, that cause a high steepening of the cornea but are not considered a form of Astigmatism. We evaluate our patients at every routine eye examination for these different types of conditions.