Astigmatism (uh-STIG-muh-tiz-um) is a common and generally treatable imperfection in the curvature of your eye that causes blurred distance and near vision.

Astigmatism occurs when either the front surface of your eye (cornea) or the lens, inside your eye, has mismatched curves. Instead of having one curve like a round ball, the surface is egg shaped. This causes blurred vision at all distances.

Astigmatism is often present at birth and may occur in combination with nearsightedness or farsightedness. Often it's not pronounced enough to require corrective action. When it is, your treatment options are corrective lenses or surgery.

Aug. 10, 2017
  1. What is astigmatism? American Academy of Ophthalmology. http://www.geteyesmart.org/eyesmart/diseases/astigmatism.cfm. Accessed July 5, 2016.
  2. Mian SI. Visual impairment in adults: Refractive disorders and presbyopia. http://www.uptodate.com/home. Accessed July 5, 2016.
  3. Astigmatism. American Optometric Association. http://www.aoa.org/x4698.xml. Accessed July 5, 2016.
  4. Astigmatism symptoms. American Academy of Ophthalmology. http://www.geteyesmart.org/eyesmart/diseases/astigmatism-symptoms.cfm. Accessed July 5, 2016.
  5. AskMayoExpert. Refractive laser surgery. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2016.
  6. What causes astigmatism? American Academy of Ophthalmology. http://www.geteyesmart.org/eyesmart/diseases/astigmatism-cause.cfm. Accessed July 5, 2016.
  7. Barbara Woodward Lips Patient Education Center. Surgery to improve your vision: PRK and LASIK. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2008.
  8. Yanoff M, ed., et al., eds. LASIK. In: Ophthalmology. 4th ed. Edinburgh, U.K.: Mosby Elsevier; 2014. https://www.clinicalkey.com. Accessed July 5, 2016.
  9. Astigmatism treatment. American Academy of Ophthalmology. http://www.geteyesmart.org/eyesmart/diseases/astigmatism-treatment.cfm. Accessed July 5, 2016.
  10. Preferred practice pattern guidelines: Refractive errors and refractive surgery PPP — 2013. American Academy of Ophthalmology. http://www.aao.org/preferred-practice-pattern/refractive-errors--surgery-ppp-2013. Accessed July 5, 2016.
  11. Bower KS. Laser refractive surgery. http://www.uptodate.com/home. Accessed July 5, 2016.
  12. Softing Hataye AL (expert opinion). Mayo Clinic, Rochester, Minn. July 20, 2016.
  13. Frequency of ocular examinations — 2015. American Academy of Ophthalmology. http://one.aao.org/clinical-statement/frequency-of-ocular-examinations--november-2009. Accessed July 6, 2016.
  14. Opticians, dispensing. U.S. Department of Labor. http://www.bls.gov/ooh/healthcare/print/opticians-dispensing.htm. Accessed Jan. 19, 2015.
  15. Astigmatism. National Eye Institute. https://nei.nih.gov/healthyeyes/astigmatism. Accessed July 20, 2016.