Astigmatism is a common refractive error of the eye, meaning the eye doesn’t focus light evenly onto the retina. It occurs when the cornea (the clear front surface of the eye) or the lens inside the eye is not perfectly spherical. Instead of being shaped like a round ball, it may be more oval or football-shaped. This irregular shape causes light to be focused at multiple points, either in front of or behind the retina, which results in blurry or distorted vision.
Types of Astigmatism:
- Corneal astigmatism: The shape of the cornea is irregular, which is the most common type.
- Lenticular astigmatism: The lens inside the eye is irregularly shaped.
Astigmatism often occurs along with other refractive errors, like nearsightedness (myopia) or farsightedness (hyperopia).
Symptoms of Astigmatism:
- Blurry or distorted vision at all distances.
- Eyestrain or headaches (especially after reading or other close-up tasks).
- Difficulty seeing clearly at night or in low-light conditions.
- Squinting to see better or feeling like you need to tilt your head to see clearly.
Causes:
- Genetics: Astigmatism is often inherited, meaning it can run in families.
- Eye injury or surgery: In some cases, injury or surgery can change the shape of the cornea or lens.
- Keratoconus: A condition where the cornea gradually becomes thinner and more cone-shaped, which can lead to severe astigmatism.
Treatment:
Astigmatism can be corrected with several methods:
- Eyeglasses: The most common and simplest way to correct Lenses are shaped to compensate for the irregular curvature of the cornea or lens.
- Contact lenses: Special toric contact lenses are designed to correct astigmatism.
- Refractive surgery: Procedures like LASIK (Laser-Assisted in Situ Keratomileusis) or PRK (Photorefractive Keratectomy) reshape the cornea to correct the irregular curvature, improving vision.
If you have astigmatism, it's often discovered during a routine eye exam. It can vary in severity, so some people might need correction, while others may have only mild effects.
