What are the risks of PRK?

Dr. Gary Foster – Fort Collins & Loveland, CO

Risks of PRK

Is PRK right for you?

PRK eye surgery has been performed in the U.S. since 1985. Since then, millions have had PRK to improve their vision. It has a great and a long safety record. Having said that, PRK is still a surgery so there are risks you should consider as you make your decision.

Accuracy of PRK

PRK has the ability to take even large glasses prescriptions and reduce them to almost perfect. It is important to notice the word almost. Eye laser surgery tends to get you to really close, but not quite perfect. Most laser vision patients would see a bit better if they put on thin glasses, but they see well enough that it isn’t worth wearing them. The results of PRK eye surgery and LASIK surgery are very similar. If you demand perfection, then laser eye surgery may not be right for you.

If your result is not acceptable, then a small amount of additional laser can be applied to bring you closer to your goal if it is medically prudent.  Check with your surgeon to find out if there are any costs associated with touchups.

Eye Infection

Like any surgery, you are at risk for an infection while you heal from your PRK.  This is extremely rare since most having laser eye surgery are healthy.  Eye infections tend to be mild and resolve quickly, but if infection goes untreated or is resistant to treatment, corneal scaring and vision loss can occur.  Diligent use of your antibiotic eye drops helps prevent this.

Corneal Haze

We want your immune system to be active to prevent infection, but if it is overactive, you can form some haze on the cornea.  To prevent this, your surgeon will have you take anti-inflammatory drops after surgery.  Protecting your eyes from the UV rays with sunglasses and a hat will further decrease your chances of haze.  There is some evidence that taking vitamin C is also helpful.  Mitomycin C can be applied at the time of PRK to decrease haze.

If you have a history of keloid formation, which is a form of over-healing, then please let your surgeon know.  This will allow a careful discussion about whether PRK surgery is right for you.

PRK Pain?

Eyes recovering from surgery can be uncomfortable and light sensitive.  A series of different comfort drops and pills are made available to make sure you are comfortable while you heal.  Some don’t need anything for comfort, while others make use of both the drops and the pills.  If you are not able to take these medicines, you will need to make an alternative plan with your surgeon to make sure your recovery is pleasant.  I performed PRK on a close friend to improve his vision.  He stayed at my home while he healed.  For those first few days, I had to call and remind him several times to take it easy because he kept trying to fix things around my house.  He just needed the eye drops to remain comfortable and didn’t use any of the Vicodin I had prescribed.  His vision was about 20/40 those first few days and then got better every day after that for about a week.  He flew home that same week.  You would have your own individual healing path, but my friend’s experience is typical.


Some are born with weaker than normal corneas.  If there is significant weakening, the cornea can lose its normal round shape, which causes blurry vision.  This weakening process is called ectasia.  Eye rubbing can speed the changes.  If you have a weak cornea and then have eye laser surgery, ectasia can accelerate.  Tests are done ahead of time to determine if you have an above average risk for this.  Fortunately, PRK has less chance of causing ectasia then Lasik.

We do know how to strengthen a cornea that shows signs of weakness and it is actually pretty easy to do.  It is called crosslinking.  The problem is that it is not currently FDA approved, but studies are ongoing and promising.

Dry Eye

You will likely experience an increase in dry eye symptoms for the first 3-6 months after PRK.  These tend to resolve completely, but on rare occasions, persist and cause problems with eye comfort and visual consistency.  PRK tends cause less dryness than Lasik.  A number of treatments are available to relieve dry eyes.

Is PRK right for you?

Fortunately, problems with PRK are rare and most have a cure, but I tell my friends that it doesn’t matter if the risk is one in a million if you are the one.  I have had eye laser surgery.  Prior to my vision correction procedure I considered my strong desire for improved vision against the potential risks and decided eye surgery was the right decision for me.  You will need to consider your personal motivation to be more glasses independent and weight that against your individual risks.  If I can help you as you make your decision, please contact my office for a no charge evaluation or drop me a line.


  1. Sherrie says:

    I had PRK over a year ago.. I, now, get severe eye strain in that eye. I use ketorolac gtts, but if I don’t use, I can’t open eye in am. It feels like it’s the superior rectus muscle. Is this normal? My vision still fluctuates bad. Is it possible to get regular LASIK on the other eye. ( I had RK on both eyes 20 yrs ago). Any help appreciated.

    • Sherrie: Most surgeons feel PRK is safer than LASIK in individuals that have had previous RK (sorry for all the acronyms), though it makes sense to consider solutions to the problems in your first eye before you consider elective surgery in your second eye.

      If the eye is both irritated and red superiorly on a regular basis, it is possible that you have a condition called Superior Limbic Keratitis (SLK (again with the acronyms)). An eye exam with your eye doctor would answer this question. If it is SLK, the troubles could potentially be cured with the right treatment. The SLK would most likely not be related to your previous PRK or RK.

      There are other conditions eye conditions that can affect the underside of our upper eye lid that can cause the troubles you describe. Another possibility is recurrent corneal erosions. Again, a good eye doctor could help if any of these are present. There are a host of eye conditions that can cause the sensitivity you describe. If you are not making progress, then a second opinion with a corneal specialist could be considered.
      God Bless,
      Gary Foster

    • You have to wait 14 painfully weaks

  2. I have been considering having LASIK for quite some time now and recently had a couple of consultations to finally go ahead with it.
    During the first consultation I was told that PRK would be a better choice for me because my corneas are on the thinner side but that it may be possible to have LASIK. I was told it would ultimately be up to the surgeon. A lifetime plan for enhancement was also added to my price because I was told I had a higher chance of regression.
    At my second consultation I was told that I definitely could not have LASIK due to a combination of my prescription (myopia and high astigmatism), thin corneas, pupil size and slight dry eye. I was also told that I would have a 15% chance of regression and would not have an option for enhancement after surgery because I would be left with only 400 microns of cornea tissue.
    Is laser eye surgery really a good option for me? I’m not feeling too confident and would really like an unbiased opinion. Any advise would be greatly appreciated.

    • Mel: It sounds like you are on the edges of what laser vision correction can achieve. Using 400 microns as the cut-off is a conservative stance that errors on the side of safety (after all, LASIK routinely goes down to 300 microns). I am not aware of any science that makes the 400 number the right choice other than that it is an easy round number. If you saw several different, skilled, and careful surgeons, you would find a difference of opinion with many having performed countless surgeries past the 400 micron depth. There is inherent risk in any elective surgery. You and your surgeon will need to have a careful discussion about the potential risks and benefits of the depth of treatment.

      If you have prk with your current surgeon and do need an enhancement, he/she is saying they wont do it. If you were to then transfer to another surgeon for the enhancement you would have to pay all over again. If, however, you start with a surgeon that is willing to go a bit past 400 and an enhancement is needed, it would fall under their enhancement policies.

      Another approach would be to look into the phakic IOL’s. The visian toric lens was just deemed approvable by the FDA and is awaiting the final panel process. No corneal tissue is removed with phakic IOLs which is a blessing for those like you with thin corneas and large prescriptions.
      God Bless with your decisions,
      Gary Foster

    • go for icl

  3. Dr. Foster,

    I am a male in my low 20’s. For the past 4 years, several optometrists and ophthalmologists told me I had dry eyes and MGD. Then one eye doctor finally said it was actually horrible allergies causing inflammation which caused them to be severely dry (at one point TBUT of 2 seconds per eye accoring to eye doctor). This now makes perfect sense because I have horrible GPC and cannot wear contacts without them moving and Lotemax, pred forte etc are not doing anything to the GPC. In any case, I fear that if I do LASIK and they get drier, what if my allergies cause even more dryness. It was unbearable before. I couldn’t imagine worse.

    So now I am contemplating PRK. I think it would be best to stay away from LASIK due to dryness I had even if that was 100% due to the perennial conjunctivitis. Is this good logic or do you think that isn’t enough to rule out LASIK?

    There are so many people who write stuff online complaining of dryness after PRK. Any studies showing this goes away after a few months?

    Thanks for your time!

    • Nate:
      Sorry for all your eye discomfort. If your eye problems have been caused by your contact lenses leading to the GPC then stopping contact lenses for six months and careful medical treatment would be expected to resolve the problem. If this happened, and you were symptom free then all of the refractive surgical options could be carefully considered with an experienced surgeon.

      If treatment resolves the GPC but you still have symptoms then it would likely indicate you have additional problems, which could be MGD, dry eye, and or allergies. We do not have good science to help us predict which patient will end up being the rare patient with symptomatic dry eye after prk or LASIK. However, if you are already profoundly symptomatic and on every treatment available, there is nothing left for your eye doctor to add if you happen to be the rare one that get more eye symptoms after refractive surgery. Some patients with these types of problems consider a phakic IOL (visian icl) rather than prk or LASIK to minimize the corneal nerve impact of the surgery.
      God Bless,
      Gary Foster

  4. Christine Lee says:

    I had PRK 3-4 years ago with great results, no dry eye. Now, my eyes feel parched at times. I have to use the computer a lot due to work and I have experienced eye strain in one eye. The symptoms are getting better and I take breaks as often as I can. I have noticed some neovascularization in both eyes which are not going away and I am concerned. I went to a highly recommended cornea specialist and another highly recommended ophthalmologist and they both said my cornea is perfect. That I have dry eye. I have heard that there are no long term side effects of eye strain. It that true? Also, I am worried about the long term side effects of PRK now that I am 3-4 years post PRK. My friend had perfect results with PRK and the safety profile was tolerable which is why I went with PRK and now I am worried. The more I read on it the more I am worried. Does eye strain get better and neovascularization (mild) resolve with time? Also, does the cornea have capacity to heal post PRK? I had mild myopia at time of surgery and my reason pre-surgery was because eyeglasses always gave me headaches and i didn’t want to wear contact lens for life. Please help and I would appreciate any recommendations. God bless you.

    • Christine:
      As you probably know, neo vascularization means that blood vessels have grown into the outer edges of your cornea, which are normally free of any blood vessels. Neo vascularization usually comes from chronic contact lens use. The contact lenses choke the cornea for oxygen, so the blood vessels grow into the cornea in response to the hypoxia (lack of oxygen). Usually, when an individual stops where contact lenses, the blood vessels stop growing in, and often thin out over time (less blood pumps through them). Now that you have had PRK and don’t need contacts, this may improve for you over time. There are other causes of neo vascularization like atopic diseases. If you have another cause for the blood vessels and still have the problem, then the neo vascularization could continue to worse as the root cause would not have been addressed by stopping contacts.
      The most common cause for eyestrain is dry eye. A careful, extended trial of dry eye treatment helps a patient know if dryness is the cause of the strain. If you are far sighted in one of your eyes, it would also cause eyestrain. Your eye doctor can find out your prescription to see if you are farsighted and whether an enhancement would help solved the issue.
      God Bless,
      Gary Foster

  5. I have minimal wet macular degeneration (AMD) in my right eye and minimal dry AMD in my left eye.

    I had a cataract in my left eye that was greying my vision. My dr removed it and implanted a trulign toric lens. My friends have had this lens implanted and rave about their increased close-up and far away vision. Only my intermediate vision has increased.

    I’m concerned that during the surgery, the Aurora laser equipment wouldn’t approve the lens being positioned where the dr wanted to position it. I heard him say, “I’m going to go with my own measurements.” I suspicion this is why I didn’t get better vision, altho the dr denies this, saying he had overridden the equipment previously, with no problem. I now have glasses for close-up and far away vision.

    It’s been a year and my vision has remained the same. I’ve heard this toric lens can be remove and another one implanted, but that scares me. I’m considering having LASIK to at least increase my long distance vision for safer driving. I have no problems with eye strain and feel no dryness in m y eyes, altho the techs say I have “slight dryness” when they screen my eyes.

    Am I safe to consider LASIK or PRK in my left eye, given the minimal AMD?

    Thanks for providing a safe place for people to get a professional second opinion.

    • Lynn:
      I am sorry to hear that you have macular degeneration. A good surgeon will override the ORA if corneal edema has developed during the cataract surgery as edema would throw off the ORA measurements and make the calculations taken before surgery more accurate. The important question is what is limiting your vision, the AMD or a prescriptive error? If your macular degeneration is limiting your vision so glasses do not improve your vision then PRK would not offer much help. If your vision is blurry because your have prescriptive error (nearsighted, farsighted, or left over astigmatism) and your vision is improved by glasses for distance, PRK could be considered to give that same level of vision without the glasses. You will need to discuss the safety of the procedure with your eye surgeon. It is often quite difficult to remove a crystalens this far out.
      God Bless,
      Gary Foster