LASIK eye surgery for treat refractive errors

What Is Refractive Surgery?

If you have a refractive error, such as nearsightedness (myopia), farsightedness (hyperopia), astigmatism or presbyopia, refractive surgery is a method for correcting or improving your vision. There are various surgical procedures for correcting or adjusting your eye’s focusing ability by reshaping the cornea, or clear, round dome at the front of your eye. Other procedures involve implanting a lens inside your eye. The most widely performed type of refractive surgery is LASIK (laser-assisted in situ keratomileusis), where a laser is used to reshape the cornea.

Laser in-situ keratomileusis (LASIK)

Laser in-situ keratomileusis (LASIK) is surgery to correct myopia, hyperopia, or astigmatism. The procedure reshapes the cornea with an excimer laser. LASIK has replaced many of the other refractive eye surgery methods.

LASIK surgery is done using a computer-controlled excimer cold laser, and a tool called a microkeratome or a femtosecond laser. With these tools, the surgeon cuts a flap in the center of the cornea to remove a thin layer of tissue. This causes the cornea to flatten. The flap is replaced without stitches and reattaches to the cornea within minutes.

Wavefront-guided LASIK is an advanced method for measuring optical distortions in the eye. The technology can be used to evaluate the eye before surgery. It measures how light is distorted as it passes into the eye and is reflected back. This creates an optical map of the eye and shows problem areas. The wavefront technology lets a LASIK surgeon adjust the laser beam settings for a more precise procedure. This can give sharper vision and reduce nighttime vision problems.

Correct refractive errors with LASIK eye surgery

For people who are nearsighted, certain refractive surgery techniques will reduce the curvature of a cornea that is too steep so that the eye’s focusing power is lessened. Images that are focused in front of the retina, due to a longer eye or steep corneal curve, are pushed closer to or directly onto the retina following surgery.

Farsighted people will have refractive surgery procedures that achieve a steeper cornea to increase the eye’s focusing power. Images that are focused beyond the retina, due to a short eye or flat cornea, will be pulled closer to or directly onto the retina after surgery.

Astigmatism can be corrected with refractive surgery techniques that selectively reshape portions of an irregular cornea to make it smooth and symmetrical. The result is that images focus clearly on the retina rather than being distorted due to light scattering through an irregularly shaped cornea.

Good candidate for LASIK eye surgery

Refractive surgery might be a good option for you if you:

• Want to decrease your dependence on glasses or contact lenses;
• Are free of eye disease;
• Accept the inherent risks and potential side effects of the procedure;
• Understand that you could still need glasses or contacts after the procedure to achieve your best vision;
• Have an appropriate refractive error.

There is no universally-accepted, best method for correcting refractive errors. The best option for you should be decided after a thorough examination and discussion with your ophthalmologist. If you are considering refractive surgery, you and your ophthalmologist can discuss your lifestyle and vision needs to determine the most appropriate procedure for you.

References

https://www.aao.org/eye-health/treatments/what-is-refractive-surgery

https://www.hopkinsmedicine.org/healthlibrary/conditions/eye_care/corrective_eye_surgery_for_refractive_errors_85,P00515