Astigmatism

Astigmatism refers to a common vision condition that causes blurred or distorted vision. It occurs when the cornea or lens of the eye has an irregular shape, resulting in light not being evenly focused onto the retina, the light-sensitive tissue at the back of the eye.

Causes

Astigmatism can be caused by several factors:

  • Corneal shape: A normal cornea is spherical in shape, but in astigmatism, it is more oval or football-shaped.
  • Lens shape: An irregularly shaped lens can also contribute to astigmatism.
  • Genetics: Astigmatism can be inherited from parents or may develop due to certain genetic conditions.
  • Eye injury or surgery: Any damage to the eye or previous eye surgery can cause irregularities in the cornea or lens, leading to astigmatism.

Symptoms

Common symptoms of astigmatism include:

  • Blurred or distorted vision: Objects may appear blurry or stretched out in different directions.
  • Eyestrain: Increased fatigue or discomfort in the eyes after focusing on tasks for a prolonged period.
  • Headaches: Recurring headaches, especially after visually demanding activities.
  • Squinting: Squinting or closing one eye to see more clearly.

Diagnosis

Diagnosing astigmatism involves a comprehensive eye examination, which includes:

  • Visual acuity test: Reading an eye chart to assess the clarity and sharpness of vision.
  • Refraction test: Utilizing a phoropter to determine the exact prescription for corrective lenses.
  • Keratometry: Measuring the curvature of the cornea using a keratometer.

Treatment

Astigmatism can be corrected through various methods, including:

  • Eyeglasses: Prescription glasses with cylindrical lenses can compensate for the irregularities in the shape of the cornea or lens, providing clearer vision.
  • Contact lenses: Specially designed toric lenses can help correct astigmatism by conforming to the shape of the eye.
  • Orthokeratology: Also known as ortho-k or corneal reshaping, this involves wearing rigid contact lenses overnight to temporarily correct astigmatism.
  • Refractive surgery: Procedures such as LASIK or PRK can surgically reshape the cornea to correct astigmatism.

It is important to consult an eye care professional to determine the most suitable treatment option based on the severity of astigmatism and individual needs.