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LASIK vs SMILE: What Is the Difference?

LASIK reshapes the cornea under a flap; SMILE removes tissue through a small incision. Results for short sight are similar, with trade-offs in recovery.

By Vireon Medical Editorial TeamFirst published Evidence checked through

Short answer

The main difference is how the laser reaches the tissue it reshapes. LASIK lifts a thin hinged flap on the front of the cornea (the clear dome at the front of the eye) and reshapes the tissue underneath, while SMILE removes a small disc of tissue through a keyhole incision without making a flap. For short-sightedness, published studies suggest the two give broadly similar visual results, with LASIK often clearer sooner and SMILE linked to milder dry-eye symptoms in the early months. Which is more appropriate depends on the prescription, corneal shape and thickness, and the eye’s surface health.

Key points

  • LASIK uses a corneal flap; SMILE uses a small incision of under 4 mm and no flap.
  • LASIK can treat short sight, long sight and astigmatism; SMILE is used for short sight and astigmatism.
  • Reviews find similar safety, accuracy and final vision for short sight, mostly from observational studies.
  • Vision tends to clear faster after LASIK; dry-eye symptoms tend to be milder early on after SMILE.
  • Neither procedure suits everyone, and long-term comparative data are limited.

How each procedure works

Both procedures correct a refractive error (a focusing problem such as short sight) by changing the curve of the cornea, so that light focuses properly on the retina at the back of the eye4. They differ in how they get to the layer that is reshaped.

In LASIK (laser in situ keratomileusis), a flap is cut in the cornea either with a blade device called a microkeratome or with a laser. The flap is lifted, a computer-controlled laser removes a planned amount of tissue, and the flap is laid back down without stitches3.

In SMILE (small incision lenticule extraction), a femtosecond laser (an ultra-fast pulsed laser) shapes a small lens-shaped disc of tissue, called a lenticule, inside the cornea. The surgeon then removes it through an incision of less than 4 mm, which changes the corneal shape5. No flap is created.

LASIK and SMILE side by side

FeatureLASIKSMILE
Access to the corneaHinged flap, lifted and replaced3Incision under 4 mm, no flap5
Prescriptions treatedShort sight, long sight, astigmatism4Short sight and astigmatism5
Early visionUsually clears faster6Takes longer to reach the same sharpness6
Vision from about 3 monthsBroadly similar6Broadly similar6
Early dry-eye symptomsCommon; usually settle4Tend to be milder in comparative studies7
Customised treatment profilesAvailable on many laser platforms6More limited at the time of the reviews6
Summary for short-sightedness with or without astigmatism. Individual results vary.

What the evidence says

A 2019 review of 22 studies comparing SMILE with LASIK for short sight and short-sighted astigmatism found the two comparable for safety, efficacy (how well vision is corrected) and predictability (how close the result lands to the planned correction)6. LASIK gave faster early recovery of vision, while outcomes were similar from about 3 months onwards.

The same authors noted important limits: almost all the studies were observational, randomised trials were few, most follow-up lasted only 1 to 6 months, and the review searched one database without pooling the results statistically6. For overall visual results, the evidence for equivalence is therefore Moderate at best, and long-term comparisons remain Limited.

Some studies reported fewer higher-order aberrations (subtle optical distortions that can affect night vision) after SMILE, but most found no significant difference, and one found more of a particular distortion called coma after SMILE6. On this point the evidence is Mixed.

Dry eye and corneal nerves

Dry-eye symptoms are very common after LASIK and usually fade within about a month, although they can persist4. Because SMILE avoids a flap, it was expected to cut fewer of the corneal nerves that help regulate tear production.

A 2016 meta-analysis of six studies (568 eyes in total, only one of them a randomised trial) found that people reported milder dry-eye symptoms after SMILE, and tear-film stability was better at 1, 3 and 6 months. However, objective tear-production and tear-saltiness tests did not differ, and the authors concluded that dry eye after both procedures was generally temporary7. The 2019 review similarly found that corneal sensation recovered sooner after SMILE6. A modest early advantage for SMILE is plausible, but its size and lasting importance are Limited.

What may decide between them

  • Type of prescription: long sight is treated with LASIK or other procedures rather than SMILE5, and the 2019 review suggested laser platforms that compensate for eye rotation for high astigmatism6.
  • Corneal health: thin, scarred or diseased corneas, including keratoconus (a progressive thinning and bulging of the cornea), can rule out LASIK4. Similar screening applies before SMILE.
  • Existing dry eye: severe dry eye is a reason LASIK may not be advised4, and Cleveland Clinic suggests SMILE may suit some people with dry eyes better5.
  • Lifestyle: a LASIK flap can be dislodged, for example by rubbing the eye3, which some people in contact sports weigh up5.

In England, NICE considers laser corneal reshaping safe and effective for appropriately selected patients, but stresses that people should understand the risks, including not achieving the expected improvement in unaided vision, and weigh them against glasses or contact lenses2. The NHS notes that laser eye surgery is usually only available privately1.

When to seek medical advice

After laser eye surgery, contact the treating eye team straight away if you have severe pain or if symptoms get worse instead of better3. Glare, halos and sore, dry-feeling eyes are common early on and usually improve within a few months1.

Common questions

Is SMILE better than LASIK?

Not overall; for short sight, current reviews find the two broadly comparable in safety and final vision, with different trade-offs in early recovery and dry-eye symptoms67.

Can SMILE correct long-sightedness?

In its established use, no; SMILE treats short sight and astigmatism, and long sight is treated with other procedures5.

Which has the quicker recovery?

Vision usually sharpens faster in the first weeks after LASIK6, although with either procedure vision can take 3 to 6 months to fully stabilise3.

Do both have the same risks?

Largely, yes; both can cause glare, halos, dry eye and under- or over-correction45, while flap-related problems apply only to LASIK.

Bottom line

LASIK and SMILE reshape the cornea by different routes, flap versus keyhole, and for short sight they reach broadly similar end results. The practical differences lie in the range of prescriptions treated, the speed of early recovery and the early dry-eye burden, and the right choice depends on a full eye assessment.

Sources

  1. NHS. Laser eye surgery and lens surgery. NHS website; reviewed 2024. https://www.nhs.uk/tests-and-treatments/laser-eye-surgery-and-lens-surgery/. Accessed 5 November 2026.
  2. National Institute for Health and Care Excellence. Photorefractive (laser) surgery for the correction of refractive errors (IPG164). NICE; 2006. https://nice.org.uk/guidance/ipg164/resources/photorefractive-laser-surgery-for-the-correction-of-refractive-errors-pdf-1899863340595909. Accessed 5 November 2026.
  3. US Food and Drug Administration. LASIK: What should I expect during and after surgery? FDA. https://www.fda.gov/medical-devices/lasik/what-should-i-expect-during-and-after-surgery. Accessed 5 November 2026.
  4. American Academy of Ophthalmology. LASIK (laser eye surgery). AAO EyeSmart; 2026. https://www.aao.org/eye-health/treatments/lasik. Accessed 5 November 2026.
  5. Cleveland Clinic. SMILE eye surgery. Cleveland Clinic. https://my.clevelandclinic.org/health/treatments/25076-smile-eye-surgery. Accessed 5 November 2026.
  6. Lau YT, Shih KC, Tse RH, Chan TC, et al. Comparison of visual, refractive and ocular surface outcomes between small incision lenticule extraction and laser-assisted in situ keratomileusis for myopia and myopic astigmatism. Ophthalmology and Therapy; 2019;8(3):373-386. https://doi.org/10.1007/s40123-019-0202-x.
  7. Shen Z, Zhu Y, Song X, Yan J, Yao K. Dry eye after small incision lenticule extraction (SMILE) versus femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia: a meta-analysis. PLOS ONE; 2016;11(12):e0168081. https://doi.org/10.1371/journal.pone.0168081.

Article history

  • — First published.