SMILE (Small Incision Lenticule Extraction) is a flapless laser eye surgery that corrects myopia and astigmatism using a single femtosecond laser — no excimer laser, no corneal flap. A small lens-shaped disc of corneal tissue is created inside the intact cornea and extracted through a 2–4mm incision.
For full clinical detail, see SMILE Eye Surgery: What You Need to Know in the Vision Correction Procedures Compared hub.
Featured Snippet: SMILE in 60 Seconds
What it treats: Myopia -1.00D to -10.00D; astigmatism up to -3.00D. What makes it different from LASIK: No corneal flap — a small 2–4mm incision instead of a 20mm flap edge. Result: less dry eye, better corneal biomechanical stability, no flap dislodgement risk. Recovery: Similar to LASIK — functional vision in 24–48 hours. FDA-approved: Yes, since 2016. Platform: Carl Zeiss Meditec VISUMAX.
How SMILE Works
The VISUMAX femtosecond laser creates a small, precisely shaped disc of corneal tissue (the lenticule) inside the intact cornea. This lenticule is then manually extracted through a small arc incision in the surface. Removing the lenticule changes the corneal curvature, correcting the refractive error.
No excimer laser is used. No flap is created. The surgical incision is 10–20 times smaller than LASIK’s flap opening.
SMILE vs. LASIK: Key Differences
Dry eye: SMILE’s primary advantage. The procedure disrupts far fewer corneal nerves than LASIK, resulting in significantly lower rates and severity of post-surgical dry eye. Multiple randomized trials confirm this difference at 3, 6, and 12 months.
Flap risk: LASIK’s corneal flap can theoretically be dislodged by trauma — immediately after surgery or years later. SMILE has no flap and carries no such risk. This makes SMILE particularly suitable for contact athletes, military personnel, and anyone with a high risk of facial trauma.
Corneal stability: SMILE preserves the mechanically important anterior Bowman’s layer and peripheral stroma, producing better corneal biomechanical stability than LASIK.
Visual outcomes: Equivalent. Large studies show no statistically significant difference in final visual acuity or patient satisfaction between SMILE and LASIK in the overlapping treatment range.
Treatment range: LASIK’s range is broader — it treats hyperopia and higher astigmatism that SMILE cannot. For patients within SMILE’s range, outcomes are equivalent.
Recovery speed: Essentially identical — functional vision within 24–48 hours for both.
Who Is a Good SMILE Candidate?
- Myopia up to -10.00D with or without astigmatism up to -3.00D
- Adults 18+ with stable prescriptions
- Patients who prefer a flapless procedure
- Patients with borderline dry eye who want to minimize post-surgical dryness
- Athletes or active individuals concerned about flap risk
Who Should NOT Choose SMILE?
- Patients with hyperopia (SMILE does not treat farsightedness)
- Patients with astigmatism above -3.00D (outside approved range)
- Patients with very high myopia above -10.00D (EVO ICL is preferred)
Related Resources
- Can I Get Vision Correction If I Have Dry Eyes?
- Which Vision Correction Procedure Is Best for Athletes?
- Which Vision Correction Procedure Has the Fastest Recovery?
*This content is educational and does not constitute medical advice.*