LASIK, or Laser-Assisted In Situ Keratomileusis, is a widely recognized refractive surgery. It uses a laser to gently reshape the cornea, the clear, dome-shaped front part of the eye. This reshaping corrects common vision problems, ultimately reducing or eliminating the need for eyeglasses or contact lenses. This improves how light focuses onto the retina, providing clearer vision.
Correcting Nearsightedness
Nearsightedness, also known as myopia, occurs when the eye focuses light in front of the retina, rather than directly on it. This typically occurs because the eyeball is too long or the cornea is excessively curved, making distant objects appear blurry. LASIK addresses myopia by precisely removing microscopic amounts of tissue from the central area of the cornea. This flattens the cornea, moving the focal point of light backward to land directly on the retina.
By altering the corneal curvature, LASIK enables light rays to focus correctly, resulting in improved distance vision. LASIK is highly effective for a wide range of myopic prescriptions, with many patients achieving excellent uncorrected distance vision. The permanent change to the cornea’s shape often provides long-lasting results for people with nearsightedness.
Correcting Farsightedness
Farsightedness, or hyperopia, is a refractive error where light focuses behind the retina, leading to blurry vision for near objects. This condition typically arises when the eyeball is too short or the cornea is too flat. To correct hyperopia, LASIK reshapes the peripheral cornea, causing the central cornea to become steeper.
Steepening the central cornea moves the focal point of light forward, ensuring it converges properly onto the retina. This reshaping allows the eye to bend light more effectively, improving the ability to see clearly at close ranges. While effective for mild to moderate hyperopia, outcomes can vary, and high hyperopia may require alternative approaches.
Addressing Age-Related Vision Changes
Presbyopia is a natural vision change that occurs with age, usually beginning around 40. It involves the gradual hardening and loss of flexibility of the eye’s natural lens, making it increasingly difficult to focus on close objects. LASIK reshapes the cornea, the outermost layer of the eye, but it does not alter the eye’s natural lens. Therefore, traditional LASIK cannot “fix” presbyopia in the same way it corrects nearsightedness or farsightedness.
Despite this, LASIK can manage presbyopia through strategies like monovision. With monovision, one eye is corrected for distance vision, while the other is left slightly nearsighted for better near vision. The brain adapts to use each eye for its optimized focal range, which can reduce or eliminate the need for reading glasses for many daily tasks.
General Candidacy for LASIK
Suitability for LASIK involves several important factors related to eye health and vision stability. Candidates should be at least 18 years old, as vision tends to stabilize by this age. A consistent eye prescription, unchanged for at least one year, is also a requirement.
Candidates should have healthy eyes free from certain diseases, such as glaucoma, cataracts, or severe dry eye. Sufficient corneal thickness is another consideration, as the procedure reshapes corneal tissue. A comprehensive eye examination by a qualified surgeon is necessary to determine individual eligibility and ensure the procedure is appropriate and safe.