SMILE is a type of laser vision correction that reshapes your cornea through a tiny incision of just 2 to 4 millimeters, rather than the large flap created in traditional LASIK. The name stands for Small Incision Lenticule Extraction. Instead of lifting a flap and using a second laser to reshape exposed tissue, SMILE uses a single laser to carve a small disc of tissue inside the cornea, which the surgeon then pulls out through a keyhole opening. The result is the same: light focuses correctly on your retina, and you can see clearly without glasses or contacts.
How the Procedure Works
SMILE uses a femtosecond laser (the same type used to create flaps in modern LASIK) to do all the work. The laser creates a thin, lens-shaped piece of tissue called a lenticule inside your cornea. It cuts the back surface first, then the edges, then the front surface. Once the lenticule is fully shaped, the surgeon makes a small arc-shaped opening on the surface of your cornea, typically around 2 to 4 millimeters wide.
Through that opening, the surgeon slides a thin instrument between the layers to separate the lenticule from the surrounding tissue, then gently pulls it out. Removing this small disc changes the curvature of your cornea, correcting your vision. The entire procedure takes about 10 to 15 minutes for both eyes, and the laser itself fires for less than 30 seconds per eye.
The key difference from LASIK is structural. In LASIK, the surgeon creates a flap roughly 8 millimeters across, which means cutting nearly the entire surface of the cornea. SMILE’s incision is less than half that size, leaving the vast majority of the corneal surface untouched.
Who Can Get SMILE
SMILE is FDA-approved for nearsightedness (myopia) between -1 and -8 diopters and astigmatism up to 3 diopters. You need to be at least 22 years old. In Europe, approval extends further, covering myopia up to -10 diopters with a total correction up to -11.5 diopters.
SMILE does not currently treat farsightedness (hyperopia). If you’re farsighted, LASIK or PRK remain your options. And like all refractive surgeries, your prescription needs to have been stable for at least a year before the procedure.
How SMILE Compares to LASIK
The outcomes are very similar. A five-year follow-up study found overall patient satisfaction of about 92% for both SMILE and LASIK combined, with LASIK slightly edging out SMILE (93% vs. 90%). Both procedures deliver excellent visual results for the right candidates.
Where SMILE shows a meaningful advantage is dry eye. Because the small incision cuts far fewer corneal nerves than a full LASIK flap, your eyes retain more sensation after surgery. A meta-analysis found that dry eye symptom scores were significantly lower in SMILE patients at one, three, and six months after surgery. By six months, dry eye symptoms in the SMILE group had returned to their pre-surgery baseline, while LASIK patients still showed elevated symptoms at that same point. Tear film stability was also better in the SMILE group at every follow-up visit after the first week.
Corneal nerve recovery tells a similar story. At one month after surgery, nerve density in the cornea was significantly higher in SMILE-treated eyes compared to LASIK eyes. Distinct nerve fibers become visible as early as one week after SMILE, with significant recovery of nerve density and length by four weeks.
SMILE also leaves the cornea structurally stronger. Because there’s no large flap, you don’t have the rare but serious risk of flap dislocation from trauma, which can happen years after LASIK. This makes SMILE appealing for people with active lifestyles or jobs that involve physical contact.
The trade-off: LASIK treats a broader range of prescriptions (including farsightedness), and enhancements after LASIK are more straightforward. SMILE is also a newer procedure, so fewer surgeons have extensive experience with it.
Recovery Timeline
Most people notice improved vision within hours, though it continues to sharpen over the first few days. Vision after SMILE tends to stabilize a bit more slowly than after LASIK, partly because the corneal surface stays intact and the tissue needs to settle from beneath rather than from the surface.
Here’s what the return to normal activities typically looks like:
- Driving: 2 to 3 days
- Light exercise and noncontact sports: 1 week
- Swimming and contact sports: 4 to 6 weeks
You’ll use prescription eye drops for the first week or so to prevent infection and reduce inflammation. Some mild scratchiness or light sensitivity is normal in the first day or two, but most people are comfortable enough to return to desk work within 24 to 48 hours.
Enhancement Rates
Between 2% and 4% of SMILE patients need a touch-up procedure to fine-tune their results. This is comparable to LASIK enhancement rates. However, enhancements after SMILE are slightly more complex because there’s no flap to re-lift. Options include surface-based laser treatment (PRK), converting the SMILE cap into a LASIK-style flap, creating a new thin flap, or performing a second SMILE procedure deeper in the cornea.
Cost
SMILE generally costs the same as or slightly more than LASIK. The national average for LASIK is about $2,250 per eye, and SMILE pricing tends to fall in the same range or a few hundred dollars higher depending on your location and surgeon. Neither procedure is typically covered by insurance, though many practices offer financing plans. PRK, the oldest of the three main options, tends to be the least expensive.