SMILE eye surgery is a type of laser surgery that treats refractive errors such as myopia (nearsightedness), hypermetropia (farsightedness), astigmatism (blurred vision at all distances), and presbyopia (an inability to focus your eyes up close)). It is a minimally invasive surgery that uses a laser to reshape the cornea and treat these conditions). The procedure involves creating a lenticule, which is a disc-shaped piece carved into the cornea by the laser, and a tiny incision less than 4 millimeters long to remove the lenticule. Removing the piece of tissue changes the shape of the cornea, which restores refraction to normal and gives sharp vision again. SMILE is a relatively new alternative to the well-established LASIK procedure.

Some conditions can make a patient unsuitable for SMILE surgery, such as thin corneas, progressive ectasia, scars, irregular astigmatism, and a few other pathologies. SMILE surgery is performed under topical (local) anesthesia that numbs the eyes, and the procedure typically takes about 20 minutes to perform per eye. Recovery time for SMILE eye surgery is relatively quick, and patients may experience tearing, redness, pain, and a gritty sensation that lasts 6 to 12 hours.

While SMILE and LASIK generate similar results for those with myopia or astigmatism, SMILE can only correct simple forms of nearsightedness (myopia) and cannot correct farsightedness, significant astigmatism, high nearsightedness, or other vision deficits commonly known as Higher-Order Aberrations. SMILE has not been proven to provide better visual outcomes or faster recovery as compared to wavefront-guided LASIK refraction.