LASIK eye surgery
What is LASIK eye surgery?
LASIK surgery meaning: any refractive eye surgery involving the cornea or lens. Primary uses are LASIK for astigmatism, LASIK for myopia , hypermetropia and presbyopia.
Refractive defects can be corrected using various types of LASIK eye surgery procedures: the primary classification is between corneal and intraocular surgery. Normally, these sight defects can be corrected by wearing glasses or contact lenses.
Is LASIK worth it? Surgery is generally advised or can be a solution when sight aids are problematic, as in cases of intolerance to lenses, work activities where contact lenses cannot be used, or simply to free oneself from such aids during daily life. The defect’s value must be measured by an ophthalmologist, who must acquire a series of data before LASIK surgery.
The most important data are measuring the sight defect, corneal topography (the curvature of the eye surface), pachymetry (corneal thickness measurement) and pupil diameter.
The most widespread types of LASIK surgery include:
PRK laser eye surgery (Photo Reactive Keratectomy, or refractive photo keratectomy) is effective on myopia, astigmatism and hypermetropia. This technique uses excimer lasers, which remove the tissue by evaporating it precisely, at a scale of thousands of a millimeter (microns).
The doctor first removes the surface of the cornea, the epithelium, manually, and then performs laser ablation. In the end, a protective contact lens is applied which will be removed at subsequent stages, when the epithelium is reshaped or when the doctor deems it appropriate.
LASEK (Laser Epithelial Keratomileusis) is a treatment similar to PRK laser eye surgery, which involves lifting the original epithelium rather than removing it.
The epithelium is preserved in an alcohol solution, which also weakens its adhesion. It is lifted, but not completely removed, and folded at the side (epithelial flap). Then the excimer laser is applied as in PRK LASIK, and the epithelium is replaced to its original position, where it re-joins naturally.
The protective contact lens is applied over the epithelium to promote a faster healing of the small portion of tissue subjected to the surgery. It is very important not to knock or rub the eye for a few days.
Epi-LASIK Variant of LASEK. The epithelium is not removed from the underlying layer with an alcohol solution, but mechanically using a separate instrument called an epikeratome. This technique allows the epithelium to retain its vitality partly.