Photorefractive keratectomy (PRK) is a type of laser eye surgery. It’s used to improve vision by correcting refractive errors in the eye.
PRK predates LASIK surgery and is a similar procedure. Both PRK and LASIK work by reshaping the cornea, which is the clear front part of the eye. This improves the eye’s ability to focus.
Some people are good candidates for both PRK and LASIK. Others are better suited to one or the other. It’s important to understand the PRK procedure and how it differs from LASIK prior to deciding which is best for you. If you’re ready to throw away your eyeglasses or contacts, this is what you need to know.
You’ll discuss specific PRK procedure guidelines with your doctor prior to your surgery date. There are several steps you’ll be instructed to take.
You’ll have a preoperative appointment to have your eyes assessed and your vision tested. In preparation for surgery, the refractive error and pupil in each eye will be measured and the corneal shape mapped. The laser used during your procedure will be programmed with this information.
Let your doctor know of any prescription and over-the-counter medications you regularly use. You may need to temporarily stop taking them. If you use antihistamines, your doctor may tell you to stop taking them three days before your scheduled surgery date.
If you wear rigid gas permeable contact lenses, your doctor will tell you to stop wearing them at least three weeks prior to surgery. Other types of contact lenses should also be discontinued, usually one week before the procedure.
Your doctor may prescribe an antibiotic eye drop, such as Zymaxid, for you to start using three to four days prior to surgery. You’ll continue to take these after the procedure for around one week. Your doctor may also recommend an eye drop for dry eye.
Around three days before surgery, you’ll need to start thoroughly cleansing around your eyes, which will empty out the oil glands located near your lash line:
- Place a warm or hot compress on your eyes for five minutes.
- Gently run your finger on your upper eyelid from the inside near your nose to the outside near your ear. Do this two or three times for the upper and lower lash lines.
- Wash your eyelids and eyelashes thoroughly with a gentle, nonirritating soap or baby shampoo.
- Repeat the entire process twice each day.
Day of surgery
You won’t be able to drive and may feel very tired after PRK, so make arrangements to have someone pick you up after the procedure.
It’s a good idea to eat a light meal before you arrive. You should expect to be at the clinic for several hours. Unless you’ve been told otherwise, take your usual prescription medications.
Don’t wear makeup or anything that might interfere with the surgeon’s ability to position your head underneath the laser. Other accessories to avoid include barrettes, scarves, and earrings.
Wear comfortable clothing to your procedure. If you’re sick, have a fever, or don’t feel well in any way, call your doctor and ask if the procedure should continue.
Ask your doctor if you should bring eye drops or any other medication with you.
PRK takes 5 to 10 minutes per eye. This type of surgery doesn’t require general anesthesia. You may be given local anesthesia or anesthetic eye drops in each eye.
During the procedure:
- An eyelid holder will be placed on each eye to keep you from blinking.
- The surgeon will remove and discard the corneal surface cells of your eye. This may be done with a laser, blade, alcohol solution, or brush.
- The laser that was programmed with your eyes’ measurements will reshape each cornea, using a pulsing beam of ultraviolet light. You may hear a series of beeps while this is being done.
- A clear, nonprescription contact lens will be placed on each eye as a bandage. This will keep your eyes clean, avoiding infection during the healing process. The bandage contact lenses will remain on your eyes for several days to one week.
You can expect to feel discomfort or pain for up to three days following PRK surgery. Over-the-counter pain medication is often sufficient for handling this discomfort.
If you’re concerned about pain or experience more pain than you can handle, ask your doctor for prescribed pain medication. Your eyes may also feel irritated or watery.
You may find that your eyes are more sensitive to light while they’re healing. Some people also see halos or bursts of light for days or weeks following PRK, especially at night.
You may also experience corneal haze, a cloudy layer that can significantly obstruct vision, for a short period of time after surgery.
While considered safe, PRK surgery is not without risk. Risks include:
- loss of vision that can’t be corrected with eyeglasses or contact lenses
- permanent changes to night vision that include seeing glare and halos
- double vision
- severe or permanent dry eye
- diminished results over time, especially in older and farsighted people
After surgery, you’ll rest at the clinic and then go home. Don’t schedule anything else for that day other than resting. Keeping your eyes closed may help with recovery and with your overall comfort level.
The doctor may wish to see you the day after the procedure to assess the results and your comfort level. Call your doctor immediately if you notice any signs of an eye infection, such as:
Let your doctor know immediately if the bandage contact lens is dislodged or falls out. You’ll need to return within seven days to have the lenses removed from your eyes.
Initially, your vision may be better than it was before the procedure. It will, however, become somewhat blurry during the first few days of recuperation. Then it’ll improve significantly. Many people notice an improvement in vision when they have their bandage contact lenses removed.
Don’t rub your eyes or dislodge the contacts covering them. Keep cosmetics, soap, shampoo, and other substances out of your eyes for at least a week. Ask your doctor when you can wash your face with soap or use shampoo.
Your doctor may recommend taking some time off while your eyes heal. Talk to your doctor about driving, reading, and computer use. These types of activities will initially be difficult. Driving should be avoided until your eyes are no longer blurry, especially at night.
Try not to get sweat in your eyes for at least a week, as this may cause irritation. Don’t participate in contact sports or any activity that might cause damage to your eyes for at least one month.
Wearing protective eye gear for several months is a good idea. Swimming and other water sports should be avoided for several weeks, even with goggles. Also, try not to get dust or dirt into your eyes for that same period of time.
It may take several weeks before your vision stabilizes completely. Vision typically improves around 80 percent after one month, and 95 percent by the three-month mark. Around 90 percent of people have 20/40 vision or better by three months after the surgery.
Shield your eyes from bright sunlight for about a year. You’ll need to wear nonprescription sunglasses on sunny days.
The cost of PRK varies based on where you live, your doctor, and the specifics of your condition. On average, you can expect to pay anywhere from $1,800 to $4,000 for PRK surgery.
PRK and LASIK were both designed to correct refractive vision problems by reshaping the cornea. Both procedures use lasers and take around the same amount of time to perform.
With PRK, the surgeon removes and discards the cornea’s outer epithelial layer, which leaves the eye exposed, prior to reshaping the cornea. This layer regenerates itself and grows back over time.
With LASIK, the surgeon creates a flap out of the epithelial layer and moves it out of the way in order to reshape the cornea underneath. The flap is usually made with a bladeless laser. It remains attached to the cornea and is put back in place after the procedure is completed.
In order to be eligible for LASIK surgery, you must have enough corneal tissue to make this flap. For this reason, LASIK may not be suitable for people with very poor vision or thin corneas.
The procedures also differ in terms of recovery time and side effects. Recovery and vision stabilization is slower with PRK than it is with LASIK surgery. People having PRK can also expect to feel more discomfort afterward and experience more side effects, such as corneal haze.
Success rates are similar for both procedures.
- can be done on people who have thin corneas or less corneal tissue caused by poor vision or severe nearsightedness
- less risk of removing too much of the cornea
- less expensive than LASIK
- less risk of complications caused by the flap
- dry eye is less likely to result from PRK surgery
- healing and visual recovery take longer because the outer layer of the cornea needs to regenerate itself
- slightly higher risk of infection than LASIK
- blurry vision, discomfort, and sensitivity to light are typically experienced while wearing the bandage contact lens during recovery
PRK and LASIK are both considered safe and effective procedures that dramatically improve vision. Deciding between the two can be difficult unless you have specific conditions that require that you do one or the other.
If you have thin corneas or poor vision, your doctor will guide you toward PRK. If you require a quick recovery, LASIK may be a better choice.