LASEK - Laser-Assisted Sub-Epithelial Keratectomy, is the laser procedure intended to correct a person's vision, reducing dependency on glasses or contact lenses without deeper corneal tissue injury. LASEK permanently change the shape of the corneal surface using an eximeer laser to ablate (remove by vaporization) a small amount of tissue. The outer layer of the cornea is removed prior to the ablation. The outer layer of the cornea, or epithelium, is a soft, rapidly regrowing layer in contact with the tear film that can completely replace itself from limbal stem cells within a few days with no loss of clarity.
The use of the anti-metabolite Mitomycin C (MMC), which is referred as M-LASEK, can minimize the risk of post-operative haze in persons requiring larger LASEK corrections (more then -5,0D or +4,0D).
Unlike LASIK, LASEK does not involve a knife, microtome, or cutting laser, but there may be more postop pain and slower visual recovery to maximal result (up to 4-6 weeks).
Unlike LASIK, LASEK does not have an increased risk of dislocated corneal flap, which may occur with trauma after LASIK.
Up to 80% of the myopic population may be as potential LASEK candidates (for M-LASEK even more)
LASEK is more reccomended for persons with increased risk of eye injury (builders, welders, policemens, soldiers, prof. sportsmens and etc.)
There are a number of basic criteria which a potential candidate should satisfy:
- Normal ocular health
- Age 18 years or older
- Stable refraction error (no noticeable change in the last year) correctable to 20/40 or better
- Between −1.00 to −12.00D of Myopia (from -5,0D recommended M-LASEK)
- Not pregnant at the time of surgery
- Realistic expectations of the final results (with a complete understanding of the benefits, as well as the possible risks)
- Pupil size may be bigger than in LASIK patients
There are also some pre-existing conditions that may complicate or preclude the treatment.
- Collagen/vascular diseases
- Ocular disease (e.g.,keratoconus, glaucoma)
- Systemic disorders (e.g. diabetes, rheumathoid arthritis)