170406-N-BB534-230 SAN DIEGO (April 6, 2017) Cmdr. John Cason, program director Navy Refractive Surgery, performs the first small incision lenticular extraction (SMILE) procedure at Naval Medical Center San Diego. The SMILE procedure is the latest advancement in refractive surgery for correcting myopia or nearsightedness. (U.S. Navy photo by Mass Communication Specialist 1st Class Elizabeth Merriam/Released)