LASIK (Laser-Assisted In Situ Keratomileusis) is a surgical procedure that reshapes the eye’s cornea to correct common vision problems, aiming to reduce or eliminate the need for glasses or contact lenses. Astigmatism is a prevalent refractive error that causes blurred or distorted vision at all distances. This condition arises from an irregularly shaped cornea or, less commonly, an irregularly shaped lens inside the eye.
Understanding How LASIK Corrects Astigmatism
Astigmatism occurs when the cornea, the clear front surface of the eye, has an oblong or football-like shape instead of a perfectly spherical one. This irregular curvature causes light entering the eye to focus on multiple points on the retina, leading to blurry or distorted vision.
LASIK addresses this by using a precise excimer laser to reshape the corneal tissue. The procedure involves creating a thin, hinged flap on the cornea’s surface. This flap is then gently lifted, exposing the underlying corneal tissue. The excimer laser is then used to remove microscopic amounts of tissue, smoothing out the irregular curves of the cornea to create a more spherical shape. Once the reshaping is complete, the corneal flap is repositioned, where it naturally adheres without stitches. This precise reshaping allows light to focus correctly on a single point on the retina, improving visual clarity for individuals with astigmatism.
The Safety and Efficacy of LASIK for Astigmatism
LASIK has a long history and a strong safety record, with millions of procedures performed globally. Research consistently supports its effectiveness and safety for correcting various refractive errors, including astigmatism.
A significant number of patients achieve visual outcomes, with many reaching 20/20 vision or better. For instance, some studies indicate that up to 95% of patients achieve 20/20 vision or better, and 99.5% achieve 20/40 vision or better. Patient satisfaction rates are also high, with approximately 95% of LASIK patients reporting satisfaction with their post-surgery vision. The overall complication rate for LASIK is low, often reported as less than 1%.
Potential Risks and Complications
While LASIK is generally considered safe, potential risks and side effects exist. One common side effect is dry eyes, which can persist for weeks to months after surgery but typically resolve with time and can be managed with eye drops.
Some individuals may experience temporary vision disturbances such as glare, halos, or starbursts around lights, particularly at night. These visual effects usually improve as the eyes heal.
Other potential complications include undercorrection or overcorrection, where the laser removes too little or too much tissue, potentially requiring additional surgery or the continued need for glasses or contact lenses. Flap complications, such as the flap folding or becoming dislodged, are uncommon due to advancements in technology and surgical techniques. Although extremely rare, more serious complications like infection or corneal ectasia, a weakening and bulging of the cornea, can occur.
Determining if LASIK is Right for You
Deciding if LASIK is appropriate requires a thorough eye examination by a qualified eye care professional. This assessment determines if a patient is a suitable candidate.
Several factors are considered during this evaluation:
Individuals should have stable vision with no significant prescription changes for at least a year.
Corneal thickness is another important criterion, as the cornea must be thick enough to allow for the necessary reshaping.
Overall eye health is also assessed to ensure the absence of conditions like glaucoma, severe dry eyes, or other eye diseases that could affect healing or outcomes.
Certain medical conditions, such as autoimmune diseases, or life stages like pregnancy or breastfeeding, can also influence candidacy.