Medically Reviewed by Tom Tooma, M.D., Founder/Medical Director
When your vision is not clear without glasses or contact lenses, but you do not want to rely on those devices for the rest of your life, surgery may be a good option. You have several types of surgery to choose from, including PRK.
Table of Contents
Just like LASIK, PRK involves the use of a laser to reshape your cornea. But unlike LASIK, PRK does not rely on the use of a corneal flap. There are many types of PRK surgery your doctor might choose from to help clear your vision.
PRK has been typically recommended for people with thin corneas or if you are involved in contact sports. PRK for these indications has been largely replaced with the SMILE procedure which has a quick recovery of vision, unlike PRK, and contact sports are not a contraindication.
What Happens During PRK?
PRK, or photorefractive keratectomy, is designed to reshape your cornea by using a computer-guided excimer laser. Much like a contact lens works by altering the path of light and how it is focused on the retina, PRK works by reshaping the cornea, therefore altering the path of light the same as a contact lens.
The PRK procedure typically takes about 10 minutes to complete, according to the American Academy of Ophthalmology. Your eyes will be numbed with drops, and your doctor will use a lid holder to keep you from blinking. You will be asked to look at a target light during the procedure. You should not worry about eye movement during the procedure since the laser has a computer guided eye tracker that tracks the eye more than 1000 times a second. You should not feel any pain during the procedure.
Your doctor will remove a thin layer of cells (epithelium) from the central two thirds of your cornea. A laser will then be used to reshape your cornea. The reshaping will be based on measurements taken before your surgery. You can have wavefront- guided, wavefront optimized and topography-guided PRK. All have excellent outcomes with more than 98% of patients seeing 20/20 or better with both eyes open.
The cell-removal step makes PRK different from LASIK surgery, say researchers writing in the journal Current Opinion in Ophthalmology. In a LASIK surgical procedure, your doctor creates a flap from your cornea, and that flap is folded up to give the laser access to your cornea. With PRK, no flap is created. This makes PRK ideal for people who have thin corneas.
You should have crisp vision following surgery that will give you the freedom from having to depend on glasses or contacts. Your eyes will need time to heal, and you may have blurred vision while that healing process takes place.
PRK Comes in Many Forms
There are three types of PRK surgery – wavefront-guided, wavefront-optimized, and topography-guided PRK.
We are all born With hills and valleys on our corneal surface. Wavefront-optimized PRK averages the hills and valleys and treats the average. Wavefront-guided PRK measures the total optical imperfections in the eye including the cornea and the lens and treats all those on the cornea. Topography-guided PRK treats the optical aberrations that are present on the cornea. All three techniques result in the same chance of getting 20/20 vision. Wavefront-guided and topography-guided have a higher chance of getting better than 20/20 vision.. Currently topography-guided is the best technique to give patients the highest chance of getting better than 20/20 vision.
Your surgeon will recommend the best procedure for you.
Who Might Consider PRK?
PRK is typically recommended for people with thin corneas, who are involved in contact sports, or who have dry eyes. The SMILE procedure has replace PRK as the procedure of choice for people involved in contact sports since with SMILE there is no flap. Lasik is a better procedure for people with dry eyes since it is less likely to be associated with increased symptoms of dry eyes. This flap Lasik, available in centers with specialized Femtosecond Lasers, such as the Visumax laser, is just as safe as PRK and has a much faster recovery time than PRK.
The procedure of choice for you is best determined by consulting with a highly experienced surgeon who has multiple laser vision correction technologies to choose the best laser for your specific eye measurement findings.
If you have thin corneas, PRK might still be the best option for you. PRK tends to preserve more tissue when compared to LASIK.
Your lifestyle preferences can also play a role in your decision between PRK and LASIK. PRK or SMILE are the procedures of choice if you:
- Play contact sports, such as football.
- Engage in martial arts.
- You are in certain branches of the military.
- Habitually rub your eyes.
Since PRK surgeries there is no flap created with PRK, like SMILE, is the preferred procedure for people involved in contact sports. The Lasik flap is well healed after three months. It is extremely rare to get it dislodged unless there is a direct trauma to the cornea. Even if it is dislodged, it is safe and very effective to replace the flap and restore excellent vision that is equal to the vision before the flap was dislodged.
There is one way in which PRK and LASIK surgeries are similar: pricing.
Both are considered to be elective surgeries and therefore typically not covered by insurance.
Complications Are Possible
While your doctor will work hard to choose the surgery type that is best for you that will have the lowest risk of side effects. All surgeries do have potential risk.
According to research highlighted in Ophthalmology Times, dry eye symptoms are some of the most common issues experienced after eye surgery in the early weeks.
Fortunately, with most patients these symptoms resolve within 3 months.
The authors of this article point out that PRK surgery is designed to reduce the risk of post-operative dry eye symptoms. Recent research proves that the incidence of dry eye symptoms is lower with Lasik than with PRK.
Some patients may have pain following PRK surgery. You will be given medications to minimize the chance of you having any pain. Eye drops, such as non-steroidal anti-inflammatory drops, are very helpful in minimizing any symptoms of pain.
This can come as a surprise to patients who have friends or family members that went through LASIK surgery. These patients may feel little to no pain at all, and patients who go through PRK may be surprised that they are not having the same experience.
Your doctor may provide you with eye drops to keep your eyes moist and comfortable. You may also have oral pain medications to ease your discomfort as your eye heals.
Unlike with Lasik, visual recovery following PRK is slower and may take one to four weeks to fully recover. You should have vision that allows you to do most of your activities, including driving and reading after one week.
There is a less than 1% chance of developing corneal haze following surgery. An article in Cataract and Refractive Surgery Today points out, new medications, such as Mitomycin, and new surgical techniques are reducing the risk of haze after surgery. Following your doctor’s advice after surgery is critical to minimize the risk of corneal haze.
If you are above the age of 40, and you have started needing reading glasses or bifocals, you may consider having mono-vision or blended vision PRK. One eye is left slightly nearsighted so you can see well at far and near without glasses. Your eye doctor can demonstrate what that is like before surgery so that you know exactly what to anticipate following surgery.
Preparing for Surgery
Your doctor will ask you to stop wearing hard contact lenses in the weeks leading up to your procedure. These devices can change the shape of your cornea and make your surgery less predictable if the measurements of your prescription are not done after your eye has recovered from the effects of the lenses. Your doctor will perform serial measurements of your prescription that are spaced two weeks apart to make sure that you have consecutive measurements that are the same. If you wear soft daily wear contacts, you are typically asked to remove the lenses for one week prior to your measurements and surgery.
You will need someone to drive you to your surgery appointment and back home again. The medications used during surgery can make you feel sleepy and woozy, which can make driving or riding public transportation unsafe. Setting that up in advance can ensure you are ready when your surgery day arrives.
Your vision will remain cloudy for several days after surgery, and that may mean that you will need to step away from work until your eyes heal up a bit. Your doctor can help you understand how long you should stay away based on the work you do each day. You should plan on staying away for at least 4 days, if not a week or more.
On the day of your surgery, you will need to avoid the use of all creams, lotions, and makeup on your eye. Your doctor will need a clean surface to work on, and you can make that possible with proper planning and care.
How Can You Decide on Surgery
Reading through articles like this one can help you understand how surgery works and why one procedure might be better for you than another. But the final decision about the surgery you have should be made in consultation with your ophthalmologist.
During your conversation with your doctor, you can ask about the excimer laser that will be used during your procedure. The U.S. Food and Drug Administration regulates the lasers used in these surgical procedures. There is a list of Excimer Lasers that the FDA has approved for refractive surgeries like PRK. You will want to ensure that your doctor is using a laser that has been approved for the type of surgery you need to have.
In addition, you will need to ask your surgeon about their experience in performing this type of surgery. The equipment used plays a big role in how well your surgery will go, but the surgeon performing the procedure is the most important variable in how well you will see after surgery and your chance of getting 20/20 vision safely.
- What Is Photorefractive Keratectomy (PRK)? (September 2017). American Academy of Ophthalmology.
- LASEK (Laser Subepithelial Keratomileusis). (August 2002). Current Opinion in Ophthalmology.
- PRK, LASEK, and Epi-LASIK for Nearsightedness: Surgery Overview. (January 2018). Kaiser Permanente.
- Long-Term Results of Epi-LASIK and LASEK for Myopia. (June 2014). Contact Lens and Anterior Eye.
- LASIK vs. PRK: Which Vision Correction Surgery is Right for You? (December 2017). Michigan Health.
- When Is PRK a Better Choice Than LASIK? (January 2014). Practice Update.
- Dry Eye: PRK or LASIK? (September 2012). Ophthalmology Times.
- Mastering LASIK and PRK. (December 2017). Review of Ophthalmology.
- Old Complications of ‘New’ PRK. (May 2003). Cataract and Refractive Surgery Today.
- FDA-Approved Lasers for PRK and Other Refractive Surgeries. (March 2018). U.S. Food and Drug Administration.