PRK, or photorefractive keratectomy, is a laser eye surgery that corrects vision by reshaping the cornea, the clear front surface of your eye. It treats nearsightedness, farsightedness, and astigmatism by changing how the cornea bends light so that it focuses properly on the retina. At 12 months after surgery, roughly 90% of patients achieve 20/20 vision or better, with results comparable to LASIK.
How PRK Works
Your cornea is responsible for bending incoming light onto the back of your eye. If it’s curved too steeply, too flatly, or unevenly, light doesn’t land where it should, and your vision blurs. PRK fixes this by using an excimer laser to remove microscopic amounts of corneal tissue and reshape the surface so light focuses correctly.
The procedure itself takes only a few minutes per eye. First, your surgeon removes the epithelium, the thin outer layer of the cornea (think of it like the outermost layer of skin). Then the laser reshapes the exposed tissue underneath, making precise adjustments measured in fractions of a millimeter. The epithelium regrows naturally over the following days. A protective bandage contact lens is placed on your eye immediately after surgery to shield the healing surface.
Modern PRK uses one of two laser guidance systems. Wavefront-guided lasers map the unique imperfections in your eye and customize the treatment accordingly. Wavefront-optimized lasers use a more standardized profile designed to preserve the cornea’s natural shape. A large meta-analysis found that both approaches produce excellent, nearly identical visual outcomes, though wavefront-guided treatment showed a slight edge in reducing astigmatism and had marginally higher patient satisfaction.
PRK vs. LASIK
The biggest difference between PRK and LASIK is structural. LASIK creates a thin flap in the cornea, lifts it, reshapes the tissue beneath, and lays the flap back down. PRK skips the flap entirely and removes the epithelium instead, letting it regenerate on its own. The final visual results are similar, but the path to getting there differs.
Because LASIK requires creating a flap, it needs a thicker cornea to work safely. Surgeons typically won’t perform LASIK on corneas thinner than 500 microns and aim to leave at least 250 to 300 microns of tissue intact beneath the flap. PRK removes far less structural tissue since there’s no flap involved, making it the better option for people with thinner corneas. It’s also preferred for people at higher risk of eye trauma (contact sports, military service) because there’s no flap that could shift from an impact.
In terms of prescription range, LASIK is generally performed up to about -5.00 diopters of nearsightedness, while PRK can treat stronger prescriptions, up to around -7.00 diopters. Both procedures can correct up to about -2.00 diopters of astigmatism. The tradeoff is recovery: LASIK patients often see clearly within a day or two, while PRK recovery takes significantly longer.
What Recovery Looks Like
PRK recovery is the main reason people hesitate about the procedure, and it’s worth understanding what to expect. The first two to three days are the hardest. During this window, the epithelium is regrowing over the treated area, and your eyes will feel irritated, watery, and light-sensitive. Many patients describe it as feeling like something is stuck in their eye. Pain levels vary, but discomfort is common enough that surgeons use several strategies to manage it: chilled saline rinses at the end of surgery, anti-inflammatory eye drops, lubricating drops, and the bandage contact lens that stays in place until the surface heals.
One recent approach involves chilling the bandage contact lens before placing it on the eye, which has been shown to reduce pain perception during those early days. Your surgeon will also prescribe antibiotic drops to prevent infection while the surface is open.
After the first few days, the sharpest discomfort fades, but your vision will still be blurry. It improves gradually over weeks, not days. Most people notice functional vision returning within one to two weeks, enough to drive and work, but the full sharpness continues developing for up to three months. One patient documented in the Cleveland Clinic’s recovery timeline reported reaching 20/16 vision (slightly better than 20/20) at her three-month follow-up.
Success Rates
PRK has a strong track record. In a prospective study tracking patients for a full year, 92% of those with low to moderate nearsightedness achieved 20/20 uncorrected vision at 12 months. Among patients with high myopia (stronger prescriptions), 88.5% reached 20/20. Nearly all remaining patients in both groups achieved 20/30, which is still well within the range for driving without glasses and handling daily tasks comfortably.
These numbers reflect a single surgery. A small percentage of patients may need an enhancement procedure if their initial correction slightly over- or under-shoots the target, though this is uncommon.
Corneal Haze and How It’s Prevented
The primary risk specific to PRK (rather than LASIK) is corneal haze, a mild clouding of the cornea that can develop during healing as the tissue remodels. It’s more likely with higher prescriptions because more tissue is removed. When it occurs, it can slightly blur vision or cause glare.
Surgeons prevent this by applying a diluted medication to the corneal surface for a brief period (typically 15 to 45 seconds) immediately after the laser treatment. A large meta-analysis found this step reduces the risk of clinically significant haze by roughly 70% overall. At the six-month mark, the reduction was even more dramatic, with treated eyes showing an 88% lower rate of meaningful haze compared to untreated eyes. This preventive step has become standard practice in modern PRK.
Who Is a Good Candidate
PRK is a particularly good fit if you have thinner corneas that rule out LASIK, if you’re in a profession or sport where a corneal flap poses a risk, or if you have certain corneal surface conditions that make flap creation problematic. You’ll need a stable prescription, meaning your glasses or contacts haven’t changed significantly in the past year or two, and you should be at least 18 years old.
People with very high prescriptions, certain autoimmune conditions affecting healing, or active eye diseases like advanced dry eye or keratoconus are generally not candidates. Your surgeon will measure your corneal thickness, map the surface shape, and assess your overall eye health before recommending PRK over other options.
What to Expect on Surgery Day
The procedure is done while you’re awake. Numbing drops eliminate pain, and you’ll be asked to focus on a light while the laser works. The actual laser treatment lasts less than a minute per eye. You won’t feel the reshaping, though you may notice a faint clicking sound and a mild smell from the tissue being removed.
Afterward, the bandage contact lens goes on, and you’ll be sent home with your eye drops and instructions. Plan to have someone drive you. Most surgeons recommend taking two to four days off work, and you should avoid rubbing your eyes, swimming, and dusty environments during the first few weeks of healing. You’ll have several follow-up visits: typically within the first week to remove the bandage lens once the epithelium has healed, then at one month and three months to track your visual progress.