WHAT ARE PRK AND LASIK?

PRK stands for Photo-Refractive Keratectomy and was the original laser eye correction procedure that in the late 1980's introduced the excimer laser as an alternative to the scalpel based refractive surgery techniques. PRK provides consistently good results for the correction of a range of prescriptions for myopia, hyperopia and astigmatism. LASEK is basically a modern version of PRK.

In the last few years a newer technique, LASIK, has been developed. LASIK is an abbreviation of Laser In-situ Keratomileusis and, like PRK, it uses excimer laser technology to treat myopia, hyperopia, and astigmatism by re-shaping the cornea and altering the focusing power of the eye. LASIK has generally superseded PRK for most patients as it can treat a wider range of prescriptions with greater predictability, as well as improving the healing process significantly enabling both eyes to be treated at the same time.

LASIK - WHAT DOES THE SURGERY DO?
First, the Consultant creates a thin flap from the cornea. The laser then re-shapes the cornea beneath this flap. This can be considered like sculpting the shape of a contact lens permanently onto the cornea.
To correct short-sight, the laser removes microscopic amounts of tissue from the centre of the cornea to thin and flatten it. This moves the focus closer to, or actually on the retina. For long-sightedness, the laser steepens the cornea by removing microscopic amounts of tissue from its edge, which again pulls the focus of objects closer to, or onto the retina itself. After the laser procedure, the corneal flap is replaced where it bonds to the eye without the need for stitches. This reshaping process can also be used to correct astigmatism at the same time.