LASIK vs. SMILE vs. PRK

Last updated: October 2, 2026

LASIK, small-incision lenticule extraction commonly called SMILE, and PRK are corneal refractive procedures intended to reduce dependence on glasses or contact lenses. They differ in how the cornea is accessed, which prescriptions and eye measurements may qualify, the early recovery experience, and the tradeoffs that matter for work, sports, dry eye, and long-term eye care.

No single procedure is automatically best. A recommendation should follow a complete eye examination, stable prescription review, corneal mapping and thickness measurements, tear-film evaluation, pupil assessment, and discussion of age, health history, medications, lifestyle, and visual goals.

At-a-Glance Comparison

Procedure	Basic approach	Early recovery	Potential reasons it may be considered	Important limitations
LASIK	A thin corneal flap is created, and an excimer laser reshapes tissue beneath it	Many patients notice early improvement, but vision and dryness can fluctuate during healing	Suitable prescription, healthy cornea, stable measurements, and preference for a generally faster early visual recovery	Creates a flap; candidacy can be limited by corneal, dry-eye, prescription, health, or lifestyle factors
SMILE	A femtosecond laser creates a small piece of corneal tissue that is removed through a small incision	Recovery varies and must be discussed for the specific eye and device indication	Some qualifying nearsightedness and astigmatism prescriptions, with no LASIK flap	Approved treatment ranges and anatomy limit eligibility; it is not interchangeable with every LASIK or PRK treatment
PRK or ASA	The corneal surface layer is removed or moved aside before excimer-laser reshaping, without creating a flap	Surface healing and early visual recovery are generally slower than LASIK	Some corneal, prescription, occupation, or contact-sport considerations	More early discomfort and a longer healing period may occur; haze and other risks require follow-up

How LASIK Works

LASIK uses a laser or microkeratome to create a hinged flap in the cornea. The flap is lifted, an excimer laser reshapes the underlying corneal tissue, and the flap is returned to position. The FDA emphasizes that LASIK permanently changes corneal shape and that patients should review device-specific information, candidacy, alternatives, and risks before treatment.

How SMILE Works

SMILE uses a femtosecond laser to create a thin lenticule within the cornea. The surgeon removes it through a small incision, changing corneal shape without creating a LASIK-style flap. Eligibility depends on the approved treatment range of the specific device, the patient’s prescription, corneal measurements, eye health, and other clinical findings.

How PRK Works

PRK treats the corneal surface rather than creating a flap. The surface epithelium is removed or displaced, an excimer laser reshapes the cornea, and a bandage contact lens is commonly used while the surface heals. PRK can be considered for some patients whose corneal or lifestyle factors make a flapless surface procedure preferable, but the early recovery is usually slower.

Candidacy Factors Shared by All Three

A stable prescription and adult age within the applicable device labeling
Corneal shape and thickness appropriate for the proposed treatment
Healthy ocular surface and manageable dry eye
No eye disease or medical condition that makes healing or the expected result unacceptable
Realistic expectations about glasses, enhancements, night vision, dry eye, and age-related changes
Willingness to follow medication, activity, and follow-up instructions

Factors That May Change the Recommendation

Pregnancy or nursing, unstable prescriptions, significant dry eye, keratoconus or suspicious corneal mapping, cataracts, advanced glaucoma, retinal disease, autoimmune or healing disorders, certain medications, prior eye surgery, very high prescriptions, and contact-sport or occupational exposure may affect whether treatment is recommended or delayed.

Recovery Is More Than the First Few Days

Early visual recovery is only one decision factor. Patients should also ask about fluctuation, dry-eye symptoms, night-vision effects, activity restrictions, follow-up, enhancement options, and how future cataract measurements will be handled. Keeping a record of the preoperative prescription and corneal measurements can be helpful for future eye care.

Potential Risks and Limitations

Possible concerns include glare, halos, starbursts, double images, reduced low-contrast vision, dry eye, undercorrection, overcorrection, regression, infection, inflammation, scarring or haze, ectasia, and the possibility that glasses or additional treatment will still be needed. Procedure-specific risks should be reviewed using the patient’s examination findings and the information for the exact device being considered.

Questions to Ask During the Evaluation

Which procedures are within the approved treatment range for my prescription?
What do my corneal map, thickness, and tear-film findings show?
Why are you recommending one procedure instead of the others?
How will my work, sports, night driving, and screen use affect the choice?
What side effects are most relevant to my eyes?
What is the follow-up schedule, and who provides postoperative care?
What are the policies and limitations for an enhancement?

Related Resources

Patient Education Sources

This page provides general education. Procedure candidacy and recommendations require an individual examination and device-specific informed-consent discussion.