What is an Astigmatism?
As is true with lenses in glasses or cameras, a defect in the curvature of the lens negatively affects the quality and clarity of an image. The same logic applies to the lenses in our eyes. A naturally-occurring imperfection in the curvature of the eye’s lens, called an astigmatism, can lead to blurred vision. Those with an astigmatism often suffer from either myopia or hyperopia. Astigmatism is very common and can worsen in some cases with time. It’s important to have an eye exam to identify astigmatism or any other vision problems.
CAUSES OF ASTIGMATISM
A flaw in the curvature of the cornea (the clear covering at the front of the eye structure) or the lens can occur naturally, even from birth. When the cornea is irregularly shaped, the eye does not have the capacity to focus correctly. Ideally, a lens with no defects reflects light to a single point on the back of the eye, on the retina. An unnatural curve causes a problem in the reflective process, and light is not focused to one point. This causes a variety of symptoms, including:
- Blurred vision
- Frequent squinting
- Difficulty with night vision
- Double vision
Astigmatism can occur at any age, and can sometimes worsens over time. If you are nearsighted or farsighted, it is important that your eyes are checked for astigmatism as the condition may not be corrected with your current eyeglass or contacts prescription.
DIAGNOSIS & TREATMENT
Your ophthalmologist can employ several different tests to check for astigmatism. The simplest method is a standard chart with rows of letters getting progressively smaller. Another method is called keratometry or topography. A device called a kerometer is used to measure the curvature of the cornea by reflecting a beam of light off the cornea’s surface and measuring the image. Similarly, a corneal topographer maps out the shape of the cornea and reveals defects. The Waring Vision Institute was the first in the state to offer High Definition Wavefront Custom Aberrometry, the most accurate way to identify astigmatism available. The last testing method uses a phoropter, which is a device with multiple lenses that measures how your eyes focus light. You may have had this type of test if you wear glasses or contacts for myopia or hyperopia.
Dr. Waring and his team are superb. My astigmatism was diagnosed many years ago as being caused my degenerative keratoconus. I had done research to know about a revolutionary corneal cross-linking and Intacs treatment. This led me to Dr. Warings, his process not only saved my eye from needing an eventual transplant, but also improved my vision. Thanks to all the staff at the office for making this possible.
Treatment for astigmatism is similar to that of nearsightedness or farsightedness. Eyeglasses or contacts can be effective, but your prescription may need adjustment if you already wear one or both. Finally, laser or lens or lens implants are a popular treatment option that can more permanently correct your vision. The procedure reshapes the eye by removing small layers of tissue either on the superficial or inner part of the cornea, or by replacing the internal lens to correct for astigmatism. All surgical and non-surgical options should be discussed with our doctor and be evaluated based upon your specific condition.
Clients seeking refractive cataract surgery do so with the goals of spectacle independence, seeing as well as or better than they do with their current glasses or contact lenses, and an improvement in visual quality. To meet these objectives, we surgeons must select the appropriate IOL according to the client’s ocular health and lifestyle, minimize postoperative astigmatism, and achieve the postoperative target.