With the cultural growth of those interested in having the LASIK procedure performed on their eyes, many have forgotten that there are other surgical options available, including the original vision of LASIK, called PRK, or photorefractive keratectomy. Prior to LASIK, PRK was the most common laser surgery performed on the eyes. Following are a few of the similarities and differences between LASIK and PRK, which is still performed and preferred by some surgeons:
The corneal flap: The creation of the corneal flap is the main difference between LASIK and PRK. In the PRK procedure, no flap is created. Instead, a blade cuts a flap in the cornea, and alcohol is used to scrape it off the surface of the eye so only the area to be resurfaced is exposed. This may be more appropriate for those with thinner corneas. The LASIK procedure utilizes the creation of the flap as a natural “Band-Aid” to place over the resurfaced cornea when the procedure is completed. The thought is that this increases healing time and reduces complications such as infections on the corneal. Indeed, those who have the PRK procedure take longer to heal than those who opt for LASIK.
The excimer laser: The excimer laser is the ultraviolet laser that gently removes cells off the surface of the cornea, resulting in a reshaping of the surface of the eye. The laser works by tiny pulses of bright, cool light. Both PRK and LASIK are performed by using excimer lasers to resurface the cornea. However, PRK uses a microkeratome, which uses a blade to cut the flap of the cornea off. LASIK procedures may be performed using a microkeratome, or the new “all laser” technique that uses a laser to cut the flap.
Treatment for myopia, hyperopia, and astigmatism: Both PRK and LASIK allow for the treatment of far-sightedness (hyperopia), nearsightedness (myopia), and astigmatism. Since the procedures both resurface the cornea by using gentle pulses of laser light, the end result of each is similar.
Time required: Both procedures are outpatient and ambulatory, meaning you walk out shortly after the surgery is complete. The procedures take only a few minutes on each eye, and while the surgery may last an hour or so for both eyes, most of the time is spent preparing the surface for ablation.
After surgery and follow up care: Since the patient is given a mild sedative prior to each procedure, he or she will need a ride home from the surgeon’s office. In both LASIK and PRK, eyesight will be hazy and distorted for the first few days following surgery. In each instance, the patient will need to see the surgeon for a follow up visit 24-48 hours following the procedure. In the case of PRK, healing time is extended, and additional follow up visits may be required until visual acuity has stabilized.
As you can see, there are very few differences between the LASIK procedure and PRK. The major difference is the creation of the corneal flap, which can create a safe healing environment for the eye, but can also be the cause of many possible complications. Because of the risks involved with cutting and having a corneal flap, military personnel and many airline employees are advised to avoid laser surgery on the eye, and choose PRK over LASIK if necessary.