What is PRK?
Photorefractive Keratectomy (PRK) is a type of laser vision correction procedure that corrects problems such as nearsightedness, farsightedness, and astigmatism.
It is an alternative to LASIK and involves reshaping the cornea using a laser to improve the way light enters the eye.
How is PRK different from LASIK?
PRK (Photorefractive Keratectomy) differs from LASIK (Laser-Assisted In Situ Keratomileusis) in two main ways.
PRK works on the surface
First, in PRK, the outer layer of the cornea (epithelium) is completely removed, whereas LASIK involves creating a corneal flap.
The laser treatment must be applied to the inner layers of the cornea in both LASIK and PRK. In LASIK, a flap is made to access the inner layers of the cornea, which is then replaced. In PRK, only the must superficial layer of the cornea, called the epithelium, is removed. These cells can be removed with a mechanical brush or using an alcohol solution.
After these cells are removed, the same exact laser from LASIK reshapes the inner layers of the cornea.
Second, PRK has a longer recovery time compared to LASIK due to the absence of a flap. The LASIK flap allows for a faster visual recovery.
However, PRK allows for corneal reshaping in individuals with thinner corneas who may not be suitable candidates for LASIK.
While both procedures use an excimer laser to reshape the cornea and correct vision problems, the specific technique of corneal treatment distinguishes PRK from LASIK.
Discuss with your doctor which procedure might be best for you.
Is PRK Better Than LASIK?
There is no one-size-fits-all procedure that’s the best for everyone. In many patients LASIK or Evo ICL may be best, however, for others, it may be PRK.
This is why it is important to be seen by a refractive surgeon who has expertise in all of these procedures. That is the best way to make sure the right procedure is matched to your eyes.
The nuances of whether LASIK or PRK is better for you should be discussed with your surgeon. The good news is that virtually all LASIK surgeons also perform PRK, and vice versa. If not… you should question why.
Am I a Candidate for PRK?
Determining your candidacy for PRK involves various factors that will be assessed by your eye care professional. Here are the key considerations:
Age and Prescription:
PRK is typically suitable for individuals over 18 years old with a stable eyeglass or contact lens prescription.
PRK can treat nearsightedness, farsightedness, and astigmatism. However, the treatment range for farsightedness is much more limited than for nearsightedness.
Doctors will have different criteria for which patients they will treat. Your prescription must be considered along with other factors, such as corneal thickness and anterior chamber depth.
Historically, “borderline candidates” with thinner corneas were considered better suited for PRK than LASIK, since PRK does less thinning to the cornea. However, the Evo ICL may be even a better option for many of these patients, since it involves no thinning of the cornea at all.
Your vision prescription should have remained relatively stable for at least a year before considering PRK. Fluctuations in your prescription may impact the accuracy of the surgical outcome.
Your goal is to see great for years after your procedure. If your prescription has been moving a lot in recent years, it may be best to wait for stability.
Many measurements will be made during your consultation. PRK requires a healthy cornea with adequate thickness.
Your eye care professional will assess the corneal thickness, curvature, and overall health during the initial evaluation.
General Eye Health:
A comprehensive eye examination will be conducted to evaluate your overall eye health. Certain eye conditions or diseases might affect your eligibility for PRK. Conditions such as cataracts, severe dry eye disease, or other eye conditions might impact your candidacy for PRK.
The PRK Procedure: What to Expect
Understanding the PRK procedure and knowing what to expect during and after the surgery can help alleviate any concerns or anxieties.
It helps to know that you’re in good company… It has been estimated that 30 million people have been successfully treated with laser eye surgery.
Here is a breakdown of the PRK process:
Before the surgery, you will undergo a comprehensive eye examination, including measurements of your cornea, prescription, and general eye health. This evaluation helps determine the appropriate treatment plan for your individual needs.
During PRK, the outer layer of the cornea, called the epithelium, is gently removed. During this process, your eye is anesthetized (or numbed) so that you will not feel anything. The epithelium is removed with a brush or using an alcohol solution.
A laser is then used to reshape the inner layers of the cornea. The laser is completely painless. No flap creation is involved in PRK, which can make it suitable for individuals with thinner corneas.
Immediate Recovery and Post-Operative Care:
After PRK, you are likely to experience discomfort and blurred vision for a few days as the epithelium regenerates.
PRK tends to have the slowest recovery of vision compared to other procedures. Typically, the first 4-5 days are quite blurry and scratchy.
Your eye care professional will provide detailed instructions for post-operative care, including the use of prescribed eye drops and protecting your eyes from bright light and irritants.
Benefits of PRK
PRK offers several unique benefits compared to LASIK and other vision correction procedures. Let’s review them:
Safety and Effectiveness:
PRK has a long track record of safety and effectiveness in correcting vision problems. PRK has been around for approximately 30 years with many improvements along the way.
Lasers are more precise and consistent than ever before. Post-operative regimens have been developed to accelerate the healing process and prevent complications.
No Flap Creation:
The absence of a corneal flap reduces the risk of flap-related complications associated with procedures like LASIK.
While the incidence of flat-related complications in LASIK is quite low, it’s even lower if you don’t have a flap!
However, it’s important to understand that there are disadvantages to not having a flap. The LASIK flap allows for faster recovery, easier touch-ups (if needed), and does not come with the risk of corneal haze that PRK has. We will discuss the risk of corneal haze in the section about Risks of PRK.
Suitable for Thinner Corneas:
Individuals with thinner corneas who may not be suitable for LASIK may be good candidates for PRK. The LASIK flap comprises approximately 15-20% of the entire corneal thickness in most patients. For patients who have thinner corneas to start with, and may not be good candidates for LASIK, PRK may be a suitable alternative because of this feature.
Risks of PRK
Almost everything in life comes with a mix of advantages and disadvantages. In good candidates, the risks of PRK are uncommon. However, let’s discuss some of the important ones.
After your vision correction procedure, you want your cornea to be crystal clear. There is an uncommon side effect of PRK known as “corneal haze” in which a cloudiness to the superficial cornea occurs.
The good news is that over the years preventative measures were developed using mitomycin C (MMC). MMC can be applied to at risk patients to decrease the risk of haze.
The risk of haze is also known to be directly related to your prescription. For example, in a 2017 study of over 7,000 eyes, zero patients with moderate nearsightedness (-3D to -6D) developed haze.
The incidence of haze increases as the prescription increases. For example, a patient with a -9D prescription would be at greater risk of developing haze compared to a patient with a -4D prescription.
Of note, farsighted patients are at the highest risk of developing haze after PRK.
Some patients may need a touch-up after their vision correction procedure. These tend to be patients with more extreme prescriptions prior to their procedure.
For example, a patient with a -9D prescription is more likely to need a touch-up than a -5D prescription.
If you need a touch-up after PRK, you’ll simply have to have PRK again. This is not a big deal for most patients, however, may require a few extra days out of work or school compared to LASIK which has a faster recovery.
Longer recovery time
This is more of an inconvenience than a risk or complication, but it’s worth reiterating. PRK comes with a slower recovery of vision compared to the other vision correction procedures.
Patients should expect 4-5 days of blurry vision after their PRK procedure.
Choosing a Surgeon and Preparation Tips
Selecting a qualified and experienced surgeon is crucial for a successful PRK outcome. Consider the following tips when choosing a surgeon:
Do They Only Perform PRK
It is uncommon for a surgeon to only perform PRK. If a surgeon tells you that PRK is “the best option for every patient”, then you should seriously consider another opinion.
In our opinion, patients should be evaluated by surgeons who have experience in all areas of refractive surgery to make sure that the best procedure is available for your eyes. These areas of refractive surgery include:
1.) Laser vision correction
2.) Evo ICL
3.) Custom Lens Replacement (CLeaR)
Browse Our Database
We’ve done the work here so that you don’t have to. We’ve curated a database of experienced vision correction surgeons who perform all 3 areas of refractive surgery – laser vision correction, Evo ICL, and Custom Lens Replacement.
If you find a surgeon near you, you can contact them directly through their profile.
If you don’t find a surgeon near you, contact us, and we’ll help you.
Discuss the cost of PRK with the surgeon and their staff. Inquire about payment options, insurance coverage, and any potential financing plans
Health savings accounts may be a good option for many patients.
PRK is an amazing procedure that makes patients independent from glasses and contact lenses.
The most important thing on your journey to better vision is knowing your options, and understanding which procedure is best for your eyes.
Contact us if you have questions!
Know An Outstanding LASIK Surgeon Who Should Be Nominated?