Photorefractive Keratectomy (PRK), "Flapless" LASIK, or Advanced Surface Ablation
Wavefront-guided PRK by Los Angeles LASIK Surgeon
Excerpted from Dr. Soroudi's Book: Advanced Refractive Surgery
As a laser refractive procedure, PRK was approved by the FDA even before LASIK, and it is still the safest way to perform keratorefractive surgery. In the right candidate (e.g., near-sighted patients with or without astigmatism), PRK provides truly outstanding results while posing the least amount of risk to the patient. Studies have shown that there is also a lower risk of having dry eyes with PRK than LASIK.
In a nutshell, a cross section of the human cornea (which is only about ½ of a millimeter in thickness) looks very much like an onion (see below). It has a very thin (red) skin covering multiple white (clear) layers that are stacked up on top of one another.
The Human Cornea
In order to reshape the onion, the red skin of the onion is first gently washed away using 20% alcohol applied in a small metal well that is held on top of the anesthetized eye for about 30 seconds (see below). This does not damage the underlying cornea whatsoever. Dr. Soroudi never uses a brush or a blade to do this in order to avoid any unnecessary damage to the underlying corneal tissue.
At this point, the same (excimer) laser that is utilized to do LASIK is used to reshape the underlying corneal tissue. A wavefront map of one's eye can be utilized to also provide for a custom treatment (just as in LASIK).
Unlike LASIK, with PRK, there is no need for creating / cutting a flap as the reshaping (excimer) laser is applied directly to the surface of the cornea (hence the name surface ablation.)
Unlike LASIK, where a small flap is created to do the surgery, with PRK, the treatment is directly on the surface of the cornea, obviating the need to cut the Cornea
Once the procedure is complete, a soft, clear contact lens is placed over the eye to protect it until the epithelial cells naturally grow back. This contact lens is effortlessly removed about 7-10 days later.
In the past, especially with the older laser platforms, there was a concern that once healed from PRK, the cornea may turn hazy and cause glare. The advent of the flying spot laser has eliminated this problem, and there have been multiple studies that have shown that the application of a medication called Mitomycin-C over the treated area prevents any haze formation. Dr. Soroudi only utilizes the most advanced FDA-approved flying spot laser in his practice, and applies Mitomycin-C for every patient for the best possible outcome every single time.
With PRK, the results are identical to (if not better than) LASIK, but vision recovers much slower, and because the epithelium has been removed, depending on the patient, there is always irritation and even pain for the first 2-3 days. This is alleviated very nicely using topical anesthetic and non-steroidal anti-inflammatory eye-drops.
Unlike LASIK, where the visual acuity improves overnight, and the patient may return to work the next day, with PRK, although one's vision improves immediately, it takes at least a few days for it to get to a level where the patient is able to return to work. It may take weeks until it reaches maximum potential (especially in individuals with astigmatism). As a general rule, PRK patients are extremely happy after 3 days.
In the past, this technique was reserved for patients who:
- Had thin corneas
- Were apprehensive about LASIK
- Had a history of other refractive procedures such as Radial Keratotomy (RK)
With the advent of the new flying spot lasers and the benefits of Mitomycin-C, this procedure has become the safest and most common refractive procedure in the United States.
Schedule a Free Consultation with a LASIK Surgeon in Los Angeles
The Soroudi Advanced LASIK & Eye Center in Los Angeles offers all prospective LASIK clients free initial consultations. During your consultation, you will be able to meet with Dr. Soroudi, receive an in-depth evaluation of your condition and learn about the possible treatment options you may have available. Focused on providing personalized service, Dr. Soroudi and our entire staff makes it a point to fully address all of your questions and concerns, and work toward meeting your goals. Contact the Soroudi Advanced LASIK & Eye Center to learn more about your LASIK options in Beverly Hills and Los Angeles.