LASIK (Laser-Assisted In Situ Keratomileusis) is a refractive eye surgery that corrects common vision problems like nearsightedness, farsightedness, and astigmatism. It aims to reduce or eliminate the need for glasses or contact lenses. While LASIK permanently alters the eye’s structure, understanding its long-term results requires considering eye health and aging.
How LASIK Permanently Reshapes the Cornea
LASIK permanently changes the shape of the cornea, the clear, dome-shaped front surface of the eye. During the procedure, an ophthalmologist first creates a thin, hinged flap on the cornea’s surface using either a microkeratome blade or a femtosecond laser. This flap is then lifted to expose the underlying corneal tissue.
An excimer laser, which uses a cool ultraviolet beam, precisely removes microscopic amounts of this exposed tissue. This reshaping corrects the eye’s refractive error, allowing light to focus properly on the retina. Once the laser treatment is complete, the corneal flap is repositioned, adhering naturally without stitches. The physical change to the cornea from the tissue removal is permanent, meaning the corrected refractive error is structurally addressed.
Reasons Vision Can Change After LASIK
While LASIK’s corneal reshaping is permanent, natural processes and conditions can lead to vision changes over time, giving the impression that LASIK has “worn off.” One common cause is the natural aging of the eye, particularly presbyopia. This age-related farsightedness typically begins around age 40, affecting the eye’s natural lens, not the cornea reshaped by LASIK, making near vision difficult.
Another age-related condition affecting vision after LASIK is cataracts. Cataracts involve the clouding of the eye’s natural lens and are a common part of the aging process, affecting almost everyone who lives long enough, regardless of whether they had LASIK. Additionally, in a small percentage of individuals, the eye’s original refractive error, such as nearsightedness, can continue to progress after surgery. This progression, sometimes called regression, means the eye’s shape changes slightly, leading to a return of some blurriness. This is more common in patients with very high prescriptions before surgery.
Other eye conditions, unrelated to the LASIK procedure itself, can also impact vision. These include conditions like glaucoma or other diseases that can affect overall eye health and clarity of sight. Systemic health conditions like diabetes can also influence eye health and vision, potentially leading to changes in visual acuity over time.
Options for Vision Changes Post-LASIK
When vision changes occur after LASIK, several options are available to regain clarity. For some patients, a LASIK enhancement might be considered. This procedure refines vision if there is residual refractive error or slight regression. The enhancement typically involves re-lifting the existing corneal flap and applying the laser for small adjustments. Not all patients are candidates for an enhancement, as it depends on factors like corneal thickness and overall eye health.
If a LASIK enhancement is not suitable, or if vision changes are due to presbyopia or cataracts, alternative corrective measures are available. Glasses or contact lenses can address new refractive errors or age-related changes. For presbyopia, specialized contact lenses or other surgical options like refractive lens exchange, which replaces the eye’s natural lens with an artificial one, can be considered.
Protecting Your Vision After LASIK
Maintaining overall eye health after LASIK involves proactive steps. Regular comprehensive eye exams are important for monitoring eye health and detecting any changes or new conditions early. Protecting the eyes from harmful ultraviolet (UV) rays by wearing sunglasses that block 100% of UV-A and UV-B radiation is recommended as a lifelong habit.
Adopting a healthy lifestyle, including a balanced diet and regular exercise, supports overall well-being and eye health. Managing underlying health conditions, such as diabetes or hypertension, is also important, as these can affect ocular health and vision. Being mindful of eye strain and taking breaks during prolonged visual tasks can contribute to eye comfort and health.