What is Astigmatism?
Astigmatism is a common refractive error that causes blurred or distorted vision at all distances due to an irregularly shaped cornea or lens. Instead of being perfectly round, the cornea or lens is more oval-shaped, causing light to focus unevenly on the retina.
Causes of Astigmatism
- Irregular Corneal Shape – A cornea that is not perfectly spherical leads to uneven focusing of light.
- Irregular Lens Shape – Sometimes, the lens inside the eye has an abnormal curvature, leading to astigmatism.
- Genetics – Often inherited and may be present from birth.
- Eye Surgery or Injury – Scarring or changes in corneal shape can result in astigmatism.
- Keratoconus – A rare condition where the cornea thins and bulges into a cone shape, causing severe astigmatism.
Symptoms of Astigmatism
- Blurry or distorted vision at all distances
- Eye strain and discomfort
- Headaches
- Difficulty seeing at night
- Squinting to see more clearly
Diagnosis of Astigmatism
An eye doctor can diagnose astigmatism through:
- Visual Acuity Test – Measures how well a person can see letters at different distances.
- Keratometry – Measures the curvature of the cornea.
- Refraction Test – Determines the correct prescription for glasses or contact lenses.
Treatment Options for Astigmatism
- Eyeglasses – Most common and simple way to correct mild to moderate astigmatism.
- Toric Contact Lenses – Specially designed contact lenses that correct uneven corneal curvature.
- Orthokeratology (Ortho-K) – Special rigid contact lenses worn overnight to reshape the cornea temporarily.
- Refractive Surgery (LASIK, PRK, SMILE) – Reshapes the cornea permanently for vision correction.
Importance of Regular Eye Examinations
Astigmatism can worsen over time, and regular eye exams help detect changes early, ensuring proper vision correction and preventing discomfort.
