Photorefractive keratectomy (PRK) and laser-assisted in situ keratomileuses (LASIK) are refractive laser procedures approved to treat refractive errors such as nearsightedness and farsightedness.

An examination of the eye using a blue lightShare on Pinterest
Arctic-Images/Getty Images

The cornea is the transparent protective layer covering the front of the eye. It bends and focuses light onto the retina. If the cornea bends the light too much or too little, it leads to refractive errors.

Refractive laser surgeries reshape the cornea to change how it focuses light, producing clearer vision.

This article discusses the differences between PRK and LASIK in terms of procedure, recovery, side effects, costs, and more.

Around 800,000 laser surgery treatments take place every year. The two procedures differ in their surgical technique.

PRK procedure

In PRK, an eye doctor removes the top layer of the cornea using one of the following tools:

  • blade
  • brush
  • alcohol solution

The doctor then uses a laser to reshape the cornea.

LASIK procedure

During LASIK surgery, a doctor uses a femtosecond laser or microkeratome to make a paper-thin flap in the cornea tissue and then folds the flap back. They then use an excimer laser to reshape the cornea to correct vision issues.

Similarities in uses and procedures

The corrective portion of both surgeries to reshape the cornea is the same.

Doctors use both laser surgeries to treat the following refractive errors:

An ophthalmologist — an eye specialist — will perform both procedures in an outpatient eye surgery center. Find out more about eye doctors.

The doctor will clean and numb the eyes with drops for both techniques. They will also place an eyelid holder to keep a person from blinking.

Learn more about laser eye surgery.

There are some key post-op differences between the two procedures.

PRK post-op

After a PRK procedure, the ophthalmologist places a soft bandage contact lens over the eyes to help the corneas heal and regenerate, which takes around 3 days. A person may resume their activities once the doctor removes the bandage lens.

The doctor will suggest that a person avoid activities that may dry out or irritate the eyes for up to a week.

Vision gradually improves over 3–5 days but may take longer in some cases. During this time, a person may experience blurry vision or pain. A doctor can prescribe pain relievers.

After either procedure, a person must wear eye protection to avoid UV exposure. They will also need to use prescribed eye drops to promote healing and reduce dryness for up to a month.

LASIK post-op

After a LASIK procedure, the doctor realigns the flap, and it attaches on its own within 2–3 minutes.

Recovery time is usually only a few days and causes relatively little pain compared with techniques that do not create a flap.

A person must wear a see-through shield for a few days to protect their eyes, even while sleeping.

Dry eye is a common side effect of refractive surgeries, but it is more common in LASIK than PRK. Both surgeries may cause a person to see halos, and rings around a light. However, there are some significant differences in complications between the two.

PRK complications

People who undergo PRK may report feeling as if they have sand in their eyes. A person may see halos around lights during the first 4–6 weeks after PRK as the cornea heals. This is more common at night.

Other risks and complications associated with PRK include:

  • scarring of cornea
  • cloudiness of cornea, or cornea haze
  • cornea infection

LASIK complications

LASIK causes minimal discomfort, but as many as 20% of people report some vision issues after surgery. Diffuse lamellar keratitis will cause blurry vision, which can be due to dryness after the procedure.

Around 85–98% of patients report having dry eye a week after LASIK surgery.

LASIK may also have the following side effects:

  • hazy, foggy, or blurry vision
  • scratchy eye
  • glare
  • small red or pink patches on the white of the eye

Learn more about eye health.

The surgeries’ prices vary depending on factors such as:

  • location
  • facilities
  • existing eye problems
  • surgeon’s expertise

PRK and LASIK generally cost $1,000–$3,000 per eye. Because PRK requires fewer resources to perform, it is a more economical option than LASIK.

The LASIK usually costs $1,500–$2,500 per eye. The costs may be higher because the procedure uses two lasers (excimer and femtosecond laser).

Insurance companies do not cover LASIK or PRK, as they consider these procedures cosmetic and not medically necessary.

Learn more about Medicare coverage for LASIK.

The two procedures show no significant differences for people with low to moderate myopia in terms of:

  • long-term effectiveness
  • accuracy
  • adverse outcomes

LASIK tends to involve less postoperative pain and shorter recovery time. There is also less incidence of haze in LASIK than in PRK.

A 2017 study found that undergoing LASIK resulted in superior visual outcomes. However, people who underwent PRK had higher satisfaction rates, possibly due to the higher cost of LASIK.

Either type of surgery can over- or under-correct a person’s vision. To address this, a person can wear glasses or contact lenses or undergo additional laser surgery.

Find out what glasses or contacts opens are the best.

Not everyone is eligible for both surgeries. Doctors consider several factors when recommending the best procedure for a person.

When determining a person’s eligibility for either LASIK or PRK, doctors will consider:

  • the person’s age — over 18
  • the stability of their prescription over the last year
  • corneal thickness and health
  • the health of the entire eye
  • the severity of the refractory error and whether it is treatable with the surgery

Doctors often suggest PRK for people who are not eligible for LASIK, such as those with severe dry eye or thin corneas.

Doctors may also suggest PRK for people with active lifestyles, such as athletes. This is because PRK does not involve cutting a flap in the cornea as LASIK does. The corneal flap may become dislodged and cause further issues if a person is highly active.

People who are pregnant or nursing should not have LASIK surgery, as vision changes can happen during pregnancy.

LASIK and PRK are refractory laser surgeries that enhance vision by reshaping the cornea. The two surgeries differ in procedure and complications. LASIK offers a faster recovery time but may cost more than PRK because of the technology it involves.

A person who is considering undergoing either surgery can consult an ophthalmologist. The specialist will consider a person’s age, overall health, existing eye conditions, and lifestyle to identify the best procedure for them.