PRK, or Photorefractive Keratectomy, is a type of refractive surgery that is used to correct vision problems such as nearsightedness, farsightedness, and astigmatism. Like LASIK, PRK involves using a laser to reshape the cornea, but the main difference between the two procedures is how the laser is applied.
In PRK, the thin outer layer of the cornea, called the epithelium, is removed completely before the laser is applied to reshape the underlying corneal tissue. This allows the laser to access the corneal tissue directly, without needing to create a flap. Once the laser treatment is completed, a contact lens is placed over the cornea to protect it while the epithelium regenerates. Over time, the new epithelium grows back, and the cornea heals, resulting in clearer vision.
PRK is an older technique compared to LASIK and may have a slightly longer recovery time. However, it can be a suitable option for people who are not good candidates for LASIK, such as those with thinner corneas or other corneal irregularities.