What is an Astigmatism

Astigmatism is a common vision condition that causes blurred vision. It occurs when the cornea — the clear front cover of the eye — is irregularly shaped or sometimes due to the curvature of the lens inside the eye. This irregular shape prevents light from focusing properly on the retina, the light-sensitive surface at the back of the eye, leading to distorted or blurred vision.

Causes of Astigmatism

There are two main types of astigmatism:

1. Corneal Astigmatism: This occurs when the cornea is not evenly curved. It's the most common type of astigmatism.

2. Lenticular Astigmatism: This type occurs when the lens inside the eye has an irregular shape.

The exact cause of astigmatism is not entirely understood, but it is often present from birth and can run in families. It can also develop after an eye injury, eye surgery, or due to eye diseases.

Symptoms

Symptoms of astigmatism may include:

• Blurry or distorted vision at any distance

• Headaches

• Eye strain or discomfort

• Difficulty seeing at night

• Squinting

Diagnosis

Astigmatism is diagnosed through a comprehensive eye exam. The eye care professional might perform tests such as:

• Visual Acuity Test: Reading letters on a distance chart to measure clarity of vision.

• Keratometry: Measuring the curvature of the cornea.

• Refraction: Determining the correct prescription for eyeglasses or contact lenses.

Treatment Options

Astigmatism can usually be corrected with:

• Eyeglasses: Lenses that compensate for the uneven curvature of the cornea or lens.

• Contact Lenses: Special toric lenses designed to correct astigmatism.

• Refractive Surgery: Procedures like LASIK or PRK reshape the cornea for improved vision.

Living with Astigmatism

While astigmatism can affect quality of life, it is manageable with proper diagnosis and treatment. Regular eye exams are important to monitor changes in vision and ensure that corrective measures remain effective.