During SMILE, the femtosecond laser creates first the lower interface of the intrastromal lenticule (using an out-to-in direction, in order to minimize the length of time that the patient’s central vision is blurred), then the upper interface of the lenticule (using an in-to-out direction). The surgeon then makes a tunnel incision (usually superotemporal) measuring 2–3 mm, connecting the cap interface to the corneal surface (Video 12-1). The total time to generate the incisions is between 20 and 35 seconds, regardless of the magnitude of the refractive error. A spatula is then inserted through the tunnel incision to separate residual lenticular attachments, first within the anterior lamella and then within the posterior plane. Once both planes have been separated, microforceps are used to extract the intrastromal lenticule.
Small incision lenticule extraction procedure. Courtesy of Renato Ambrósio Jr, MD, PhD.
Access all Section 13 videos at www.aao.org/bcscvideo_section13
Ivarsen A, Asp S, Hjortdal J. Safety and complications of more than 1500 small-incision lenticule extraction procedures. Ophthalmology. 2014;121(4):822–828.
Moshirfar M, McCaughey MV, Reinstein DZ, Shah R, Santiago-Caban L, Fenzl CR. Small-incision lenticule extraction. J Cataract Refract Surg. 2015;41(3):652–665.
Reinstein DZ, Archer TJ, Gobbe M. Small incision lenticule extraction (SMILE) history, fundamentals of a new refractive surgery technique and clinical outcomes. Eye Vis (Lond). 2014 Oct 16;1:3.
Excerpted from BCSC 2020-2021 series: Section 13 - Refractive Surgery. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.