Introduction to Lasik

Lasik is a surgical process aimed at diminishing an individual’s dependence on glasses or contact lenses. Lasik is the abbreviated form of Laser-Assisted In Situ Keratomileusis and is a process that on a permanent basis alters the structure of the cornea which is the transparent cover of the front of the eye. The procedure is accomplished with the aid of an excimer laser.

A knife, known as a microkeratome, is employed for cutting a flap in the cornea with a hinge left at one edge of this flap. The stroma or the central section is revealed when the flap is folded back. The flap is substituted after pulses from a computer-controlled laser vaporize a part of the stroma.

Visual Defects

The cornea is a portion of the eye that assists in focusing light to produce an impression on the retina. Its function is similar to the lens of a camera that focuses light to produce an impression on film. Generally the structure of the cornea and the eye are not flawless and the impression created on the retina is not properly focused or indistinct. These blemishes in the focusing power of the eye are known as refractive faults. There are three principal kinds of refractive faults: myopia, hypmetropia and astigmatism. Individuals with myopia, or nearsightedness, experience greater problem perceiving distant objects clearly than objects that are seen from near. Persons with hypermetropia, or farsightedness, experience greater problem in perceiving near objects than objects positioned at a distance.

Astigmatism is a misrepresentation of the image on the retina resulting from abnormalities in the cornea or lens of the eye. Myopia and astigmatism or hypermetropia and astigmatism can generally be found among people with problems pertaining to the eye. Glasses or contact lenses are intended to make up for the eye’s defects. Surgical actions designed for enhancing the focusing efficiency of the eye are known as refractive surgery. In lasik surgery, accurate and controlled elimination of corneal tissue by an exclusive laser restructures the cornea altering its focusing capability.

Lasik and Other Refractive Surgeries

  • Radial Keratotomy or RK and Photorefractive Keratectomy or PRK are different refractive surgeries employed to remodel the cornea.
  • In RK, a knife that is exceedingly sharp is employed to make slits in the cornea altering its structure.
  • PRK was the initial surgical technique that was employed to reshape the cornea by sculpting with the help of a laser.
  • Afterwards, lasik came into existence. An identical sort of laser is utilized for both Lasik and PRK.
  • Frequently the precise identical laser is utilized for the two kinds of surgery.
  • The chief dissimilarity between the two surgeries is the manner that the stroma, the central covering of the cornea, is bared before being vaporized with the laser.
  • In PRK, the uppermost covering of the cornea, known as the epithelium, is scraped away to expose the stromal cover beneath. In lasik, a flap is incised in the stromal cover and the flap is folded back.