Femtosecond Lenticule EXtraction (FLEX) is a new form of refractive eye surgery similar to LASIK that creates a lenticule for removal and a corneal flap. Flex uses a single femtosecond laser laser - compared with Lasik's two - to cut a lens-shaped layer from within the cornea and shape it to achieve improved patient vision. The new treatment works better than Lasik for people with more severe myopia of up to 1,000 degrees. Additionally, the surgery is reversible in many cases, helping those who develop long-sightedness or presbyopia as they age. Carl Zeiss Meditec, which is developing the procedure for its VisuMax laser, has reported good initial results.