Astigmatism is one of the common disorders of vision that causes blurred vision due to the irregular shape of the cornea or the lens in the eye. Normally, the cornea and lens are smooth and evenly curved equally in all directions, helping to focus light rays clearly onto the retina at the back of the eye. Astigmatism happens when the cornea or lens is shaped more like a football or the back of a spoon, rather than a round, smooth surface. As a result, light entering the eye is not focused equally on the retina, leading to distorted or blurred vision at any distance. Astigmatism can also be present with refractive errors (myopia and hyperopia). Common astigmatism symptoms are blurred vision, distorted vision, eyestrain, headache, and problem vision at night. Correcting astigmatism is by the use of eyeglasses, contact lenses, or refractive eye surgery in some patient settings.

Corrective lenses, such as glasses or contact lenses, can usually correct vision for those who suffer from astigmatism; another possible solution, derived through advanced medical technology is refractive eye surgery.

What is Refractive Eye Surgery?

Refractive eye surgery definitions are all those general terms that denote the umbrella of various procedures taken to correct refraction errors of the eye. It is the re-shaping of the cornea to change its power of focus. Therefore, by altering its curvature, one can make the eye have better-focusing power on the retina of the light rays, thereby reducing or eliminating eyeglasses or contact lens use.

Types of Astigmatism Refractive Eye Surgery

Several types of refractive surgeries can treat astigmatism:

1. LASIK (Laser-Assisted In Situ Keratomileusis): This is perhaps the most widely known and performed refractive eye surgery. A laser reshapes the curvature of the cornea while creating a thin flap on the cornea to correct your refractive error. LASIK is effective for the treatment of mild to moderate astigmatism.

2. PRK (Photorefractive Keratectomy): Another form of laser surgery, this one is akin to the mechanics of a LASIK but without the creation of a flap. In a PRK procedure, the outer layer of the cornea (the epithelium) is removed fully before the underlying tissue is shaped with the laser. PRK is good for the treatment of astigmatism, and in some instances, can even be a better option than LASIK.

3. Laser Epithelial Keratomileusis (LASEK): There is a mixture of LASIK and PRK features. The procedure includes creating an epithelium flap, like in LASIK, but the flap is much thinner and, following reshaping the cornea with the laser, replaced.

Is Refractive Surgery Suitable for Everyone with Astigmatism?

If the treatment is appropriate, refractive surgery works for almost everyone with astigmatism. Whether an individual can undergo the particular surgery depends on a couple of factors, which include:

1. Severity of Astigmatism—Mild to moderate astigmatism is correctable via refractive surgery, but this is in contrast to severe astigmatism.

2. Corneal Thickness: The corneal thickness is significant since some of the refractive surgeries, for example, through LASIK, may have to reshape this cornea into one that is quite thick. If this thickness is less, then some of the procedures will not be relevant.

3. Stability of prescription: The prescription (degree of astigmatism) has to be the same throughout. If one is still changing prescriptions, probably it is not the right time for surgery.

4. They may also have an impact on whether surgery is appropriate – eye health in general if you are afflicted with dry eye syndrome or have keratoconus.

5. General Health and Age: Most patients are at least 18 years old and have healthy immune systems. Being pregnant or nursing is a contraindication for consideration.

6. Expectations, and lifestyle: Candidates understand the surgical outcomes, including the necessary time requirements for participating in check-up care, and aftercare recommendations.

Before Refractive Surgery

You need a thorough eye examination before refractive surgery for this purpose. An examination will include testing refraction, the shape and health of your corneas, and other eye conditions that may affect the outcome of the surgery.

It also is important to have realistic expectations when looking at the outcome of refractive surgery. While many people end up with a significant improvement — even a 20/20 vision in many cases — perfect results are not a realistic goal for everyone.

In summary, corneal reshaping surgery is a reasonable approach to astigmatism correction and reduces the need for glasses or contact lenses. Innovations for both general and surgical technology enhance outcomes and broaden the options for patient selection.

If at the back of your mind, you think that refractive surgery for astigmatism is for you, then consult with a qualified eye care specialist, measure your candidacy, and understand this procedure. Thus, you have informed your process of decision-making and, at the same time, obtained clear visions unsurpassed in attaining a better quality of life.

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Written and Verified by:

DR. HIMANSHU SHEKHAR

MBBS, MD (AIIMS, NEW DELHI) & DNB

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