Can LASIK Help My Astigmatism?

Photo: BestPhotoStudio

Photo: BestPhotoStudio

At Eye Care Specialists, we perform laser vision correction to treat all kinds of refractive errors caused by irregularly shaped corneas that don’t focus light properly. A refractive error can cause nearsightedness, farsightedness, or astigmatism. Let’s take a closer look at astigmatism, including what causes it, and whether or not it can be treated by LASIK surgery.

What is Astigmatism?

If you were to examine a normally shaped cornea, it would kind of look like a baseball.  However, the cornea of a person with astigmatism is shaped more like a football. Because of this irregular shape, light that enters the eye is not focused correctly, which skews the person’s vision. Instead of being able to focus on a single point on the retina to generate clear vision, it is focused onto multiple points, often leading to blurred or distorted vision. You may notice that some people with astigmatism frequently squint in an effort to see clearly. This is because astigmatism can make it very difficult to focus on fine details or objects. Many times, suffers of astigmatism squint so much it can cause headaches from the strain of trying to focus.

Types of Astigmatism

There are three primary types of astigmatism:

  • Hyperopic astigmatism, in which one or both principal meridians are farsighted. If both meridians are farsighted, they are hyperopic.
  • Myopic astigmatism, in which one or both principal meridians of the eye are nearsighted. If both meridians are nearsighted, they are myopic.
  • Hyperopic astigmatism, in which one or both principal meridians are farsighted. If both meridians are farsighted, they are hyperopic.

Astigmatism is also classified as regular or irregular:

  • In regular astigmatism, the principal meridians are 90 degrees apart, perpendicular to each other.
  • In irregular astigmatism, the principal meridians are not perpendicular.

Most cases of astigmatism are regular astigmatism, which gives the front surface of the eye a football shape. Irregular astigmatism can result from eye injuries or certain types of eye surgeries that scar the cornea, or from keratoconus, a disease that gradually thins the cornea of the eye.

Also, certain patients may suffer from lenticular astigmatism, caused by an irregularly shaped eye lens rather than an irregularly shaped cornea.

Can LASIK Correct Astigmatism?

Yes, but your ophthalmologist will have to examine your eyes to determine the type and severity of your astigmatism. Astigmatism is assessed during a routine eye exam with the very same instruments and techniques used to detect nearsightedness and farsightedness. Usually this is done through a test called retinoscopy, which is performed by shinning a light into your eye. Some doctors may use automated instruments that provide a faster preliminary test for astigmatism and other refractive errors.

Once a diagnosis has been made, astigmatism like nearsightedness and farsightedness, can be corrected with either eyeglasses, contact lenses, or refractive surgery. If you decide to go the LASIK route for a more permanent fix, it can work by reshaping the cornea or clear the front part of the eye so that light traveling through it properly focuses onto the retina located in the back of the eye.

If you would like to schedule an appointment to find out if you are a candidate for LASIK eye surgery, simply fill out the form on the Norwood Eye Care Specialists website, or called Norwood Eye Care Specialists at 781-769-8880.