A patient from Oxnard that I saw in my Ventura office asked me about a laser eye surgery she saw on TV called SMILE. SMILE (small incision lenticule extraction) is a new laser vision correction surgery in which the surgeon uses the femtosecond laser to separate out a thin “coin” of tissue from within the cornea and remove it from a small side incision in the cornea, also made with the laser. Once this “lenticle” is removed, the overlying cap of the cornea sinks down to change the shape of the cornea and correct myopia (nearsightedness). This is in contrast to LASIK in which a thin flap is separated from the surface of the cornea and the excimer laser is used to sculpt a new shape in the underlying corneal tissue, and the flap is put back to conform to that new shape. PRK is similar to LASIK, but no flap is made. Rather, with PRK, the same excimer laser is used to directly reshape the surface of the cornea without a flap. The excimer laser used for LASIK and PRK can be guided by different technologies for measuring the eye. If a refraction (“which is better one or two test”) is used, this is called “conventional” LASIK. If the surface of the cornea is mapped, this is called “topographically guided LASIK.” Customized wavefront LASIK involves measuring the entire optics of the eye with an infrared laser beam reflected through the eye. A study recently compared SMILE to topographically guided LASIK and showed superior results with topographically guided LASIK. In this study, topographically guided LASIK was performed in one eye and SMILE was performed in the other eye of the same patient. This is called a “contralateral eye” study and it removes genetic variables from patient to patient. In this study, 86.4% of topographically guided LASIK eyes achieved 20/20 vision without glasses, compared to 68% with SMILE. Topographically guided LASIK also was more predictable in its outcomes both for correction of nearsightedness and for astigmatism. Subjectively, patients preferred their LASIK eye over the SMILE eye.  Interestingly, previous studies have shown even further advantage to customized wavefront LASIK over topographically guided LASIK. I consider customized wavefront LASIK to represent the state of the art for most cases. Topographically guided LASIK also is an excellent approach to correcting vision with its own unique advantages for certain select patients, but may benefit in the future from integrating its optical data with customized wavefront measurements. SMILE in my opinion remains an interesting and promising laser vision correction technique, but one that is still in evolution.