LASEK eye surgery is a variation of PRK to correct myopia (nearsightedness), hyperopia (farsightedness) and astigmatism. LASEK combines certain methods from both LASIK and PRK.

LASIK remains the most popular laser eye surgery, but for people who are not suitable LASIK candidates, PRK or LASEK may be better options and produce comparable outcomes to LASIK.

Like other types of laser refractive surgery, LASEK works by reshaping the cornea using an excimer laser, allowing light entering the eye to be properly focused onto the retina for clearer vision without eyeglasses or contact lenses.

The fundamental difference in how LASIK, PRK and LASEK are performed concerns how the eye is prepared for the laser treatment:

► During LASIK, a thin circular “flap” is created on the eye’s surface using a microkeratome or a femtosecond laser surgical tool. The surgeon then folds back the hinged flap to access the stroma and reshape the corneal tissue using an excimer laser.

The flap is then returned to its original position and serves as a natural bandage, keeping the eye comfortable as it heals. The flap adheres securely without stitches, and healing occurs relatively quickly.

► During PRK, instead of creating a corneal flap as in LASIK, the surgeon completely removes the extremely thin outer layer of the cornea (epithelium, which is like a clear “skin layer” covering the cornea), using an alcohol solution, a “buffing” device or a blunt surgical instrument. The underlying corneal stroma is then reshaped with an excimer laser. A new epithelial layer grows back within five days.

► The LASEK procedure involves a little of both LASIK and PRK. Like in PRK, the corneal epithelium is separated from the underlying stromal layer. But instead of completely removing and discarding the epithelial tissue, the LASEK surgeon pushes the ultra-thin epithelial “flap” to the side (it remains attached to the eye on one side, like the thicker corneal flap made in LASIK), exposing the corneal stroma for laser reshaping.

After the laser treatment is finished, the epithelial tissue is repositioned on the surface of the eye to cover the lasered stroma, and a bandage contact lens is placed on the eye to keep the epithelium in place as it heals.

LASEK Risks and Complications

LASEK and PRK complications are similar to LASIK complications. Side effects can include vision disturbances such as:

► Blurry vision, halos and glare ► Significant over correction, under correction or regression which may require   further surgery or reliance on eyeglasses or contact lenses for some or all activities ► Dry eyes ► Eye infection and irritation

While LASEK avoids the corneal flap-related risks of LASIK, there are some complications exclusive to LASEK surgery.

In some cases, the thin epithelial flap created during LASEK is not strong enough to be replaced over the treated area and will be removed completely as it would have been in PRK. Typically, this does not pose a risk, but if you have a very high prescription for myopia you may have a greater likelihood of experiencing hazy vision.

The alcohol solution used during LASEK causes tissue damage to epithelial cells that slows the healing process immediately after surgery. Recovery after epi-LASIK typically is faster because no alcohol is used to create the epithelial sheet.

LASEK eye surgery offers a safe and effective alternative to LASIK but typically is performed only if you are not a good candidate for LASIK eye surgery, owing to the faster visual recovery and minimal discomfort associated with LASIK.