When considering vision correction surgery, two of the most common procedures that come up are PRK (Photorefractive Keratectomy) and LASIK (Laser-Assisted In Situ Keratomileusis). Both surgeries are effective in correcting refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism, but each has its unique approach, benefits, and drawbacks. Understanding the key differences between PRK and LASIK can help you decide which one might be the best fit for your vision and lifestyle. They both use the same laser, and have the same results statistically, but PRK takes a bit longer to get there.

What is LASIK?

LASIK is one of the most popular and well-known laser vision correction surgeries. It involves creating a thin, hinged flap in the cornea’s surface and reshaping the corneal tissue beneath it using a laser. Once the corneal shape is adjusted to correct the refractive error, the flap is laid back in place and the superficial skin is preserved, which allows a faster healing process. I use the analogy of placing sod on your lawn: you shape the ground underneath it, lay the sod, and it looks pretty good right away. PRK is more like planting new grass seed: it ultimately looks good, but takes longer for that surface to recover.

Benefits of LASIK

• Quick Recovery: Most patients experience significant improvement in vision within 24-48 hours after surgery. They can typically drive, exercise, use phones and computers, and bathe. The only time I’ve seen a problem with the flap moving is if someone gets poked directly in the eye- which fortunately is rare.
• Minimal Discomfort: Due to the corneal flap, there is less initial discomfort, and for a shorter period of time. LASIK discomfort is typically about 4-6 hours. PRK is about 2-3 days.
• Proven Long-Term Success: LASIK has a long track record of success and patient satisfaction, but PRK was actually the first procedure approved in the US (October 1995) and LASIK approval came a couple years later.
• Shorter Procedure Time: The surgery itself is brief, often lasting around 3 minutes per eye.

Drawbacks of LASIK

• Flap-Related Complications: Creating a corneal flap poses a small risk of flap-related complications, which can impact healing. There is a small risk creating the flap, small risk of it becoming dislodged, and small risk of corneal ectasia, a condition where the cornea can stretch, causing blur.
• Not Ideal for Thin Corneas: LASIK isn’t typically recommended for people with thin corneas, or for those with very high degrees of nearsightedness, or occasionally for patients with very deep-set eyes.
• Risk of Dry Eye: Some patients experience temporary or chronic dry eye following LASIK due to nerve disruption in the corneal flap. This is much more common in women vs. men, and older (over 40) vs younger. It’s super rare for a young man to have significant dryness after LASIK or PRK.

What is PRK?

PRK, the predecessor to LASIK, offers an alternative for patients who may not be ideal candidates for LASIK. Unlike LASIK, PRK does not involve creating a corneal flap. Instead, the top layer of the cornea (the epithelium) is gently removed, allowing the laser to reshape the underlying corneal tissue. The epithelial cells typically grow to re-cover the surface area that was treated in 3-4 days post-surgery.

Benefits of PRK

• No Flap Creation: With no flap involved, PRK eliminates the risk of flap-related complications and is a suitable option for patients with thin or irregular corneas.
• Lower Risk of Dry Eye: PRK may be a better choice for patients prone to dry eyes, since it doesn’t disrupt the corneal nerves as much as LASIK.
• Suitable for High-Risk Activities: PRK is often recommended for people involved in contact sports or physically demanding jobs where the corneal flap created in LASIK might be at risk of dislocation. MMA fighters, police officers, firefighters, and others who are concerned about their eyes getting hit may consider PRK if they’re LASIK candidates. However, not all PRK candidates are LASIK candidates. In the branches of the armed services, PRK used to be the only acceptable vision correction procedure, but because the flap risk is so low, and PRK took the serviceman or woman out of action for too long, they approved LASIK in the military many years ago.

Drawbacks of PRK

• Longer Recovery Time: PRK has a slower recovery timeline than LASIK, with full vision clarity potentially taking several weeks to a few months.
• Initial Discomfort: Because the epithelial layer needs time to regenerate, PRK patients almost always experience more discomfort and light sensitivity in the first week after surgery.
• Visual Fluctuations: Vision may fluctuate more in the initial weeks of recovery compared with LASIK, as the cornea stabilizes over time. PRK catches up statistically at about the one month post-op mark.

PRK vs. LASIK: Key Differences

• Surgical Method: epithelium removal vs. corneal flap creation
• Recovery Time: 5-7 days for functional vision vs. 12-24 hours for functional vision
• Initial Discomfort: moderate discomfort post-surgery vs. minimal discomfort due to flap protection
• Corneal Requirements: suitable for thin/irregular corneas vs. ideal for thicker corneas
• Long-Term Stability: similar long-term results as LASIK vs. proven effective for over 28 years
• Activity Suitability: no flap to move, so no additional risk-still wear safety goggles/glasses vs. flap could move only if hit directly in the eye- safety glasses always recommended.

“I use the analogy of placing sod on your lawn: you shape the ground underneath it, lay the sod, and it looks pretty good right away. PRK is more like planting new grass seed: it ultimately looks good, but takes longer for that surface to recover.”

Pros and Cons Recap

When deciding between PRK and LASIK, it’s important to weigh the pros and cons:

LASIK Pros:

• Faster return to all activities
• Immediate improvement in vision- everyone is “foggy” initially, but most can drive comfortably the next day
• Minimal post-op discomfort-usually 4-6 hours

LASIK Cons:

• Flap-related risks (e.g., displacement or wrinkling)- only with direct impact, such as a finger in the eye
• Higher likelihood of dry eye as compared to EVO ICL, but same dryness risk as PRK
• Not ideal for patients with especially thin or irregular corneal shape

PRK Pros:

• No flap, which is beneficial for thin or irregular corneas
• Good option for athletes or those with physically demanding jobs

PRK Cons:

• Longer visual recovery period
• More post-operative discomfort and light sensitivity.
• Vision fluctuations in the early weeks post-surgery- if it weren’t for the first week after PRK, we might never do LASIK!

Which Surgery is Right for You?

Choosing between PRK and LASIK often comes down to your corneal thickness, lifestyle, and willingness to undergo different recovery experiences. LASIK’s quick recovery time can be ideal for those seeking an almost immediate return to daily activities, whereas PRK is often recommended for those who are active in high-contact sports or have specific corneal conditions that make LASIK less suitable. At SHARPEVISION, we look at a number of anatomical and lifestyle factors, and discuss our reasons for our recommendation.

For example:

• Active Lifestyle: If you play contact sports or have a job that involves frequent exposure to physical risks, PRK may be the safer option since it doesn’t involve a flap.
• Dry Eye Prone: Both PRK and LASIK have the same risk of dry eye. We find this much more in women than men, and more as we get older. However, dry eye can be treated, but can be frustrating, as your vision will fluctuate along with feeling like your eyes are dry. We often recommend the EVO Implantable Contact Lens, or ICL, which has no risk of dryness due to the procedure. See our recent blog post on EVO ICL.
• Rapid Recovery Preference: If your priority is a swift return to work or daily activities, LASIK’s faster healing time may make it the better choice. If you’re concerned about the LASIK flap, or risk of getting hit in the eye, PRK works great!

Conclusions

Both PRK and LASIK are highly effective vision correction procedures, each with unique benefits and considerations. Consulting with an experienced ophthalmologist and ophthalmic team who can evaluate your eye health, corneal thickness, and lifestyle will give you personalized guidance on which procedure may offer the best outcome for you.

Deciding between PRK and LASIK isn’t just about the procedure itself, but about aligning your vision correction need with your lifestyle and goals!