title: Surface quality of human corneal lenticules after SMILE assessed using environmental scanning electron microscopy.
abstract: OBJECTIVE
  To assess the cut quality of the anterior and posterior surfaces of intrastromal refractive lenticules removed during small incision lenticule extraction (SMILE).
  
  
  METHODS
  The VisuMax femtosecond laser (500 kHz; Carl Zeiss Meditec, Dublin, CA) was used to perform SMILE on 8 eyes of 5 individuals to correct only myopia (no cylinder). The cut energy index was 26 (equivalent to an energy of 130 nJ) with a 2.5 × 2.5 μm spot/track separation. The lenticule diameter was 6.5 mm with a minimum edge thickness of 15 μm and the cap diameter was 7.3 mm with an intended thickness of 120 μm. After laser treatment, the lenticule was loosened with a spatula and removed with forceps. The extracted lenticules were placed in 2% formalin and sent for imaging with an environmental scanning electron microscope. Images of the anterior and posterior surfaces of the lenticules were obtained at multiple magnifications (100×, 250×, and 500×). Surface quality was evaluated by an investigator who specializes in electron microscopy using three criteria: overall surface regularity, percent of surface irregularity, and position of irregular area.
  
  
  RESULTS
  Both the anterior and posterior surfaces of the extracted lenticules were smooth and absent of surface irregularities. The cut edges also appeared uniform. Jagged edges were seen in several images, but were clearly caused by the forceps during extraction.
  
  
  CONCLUSIONS
  Using the VisuMax laser to perform SMILE produces smooth cuts absent of surface irregularities.
authors: Noël M
authors: NM
authors: Ziebarth
authors: Michael A
authors: MA
authors: Lorenzo
authors: Jessica
authors: J
authors: Chow
authors: Florence
authors: F
authors: Cabot
authors: Gregory J R
authors: GJ
authors: Spooner
authors: Jon
authors: J
authors: Dishler
authors: Jesper Ø
authors: JØ
authors: Hjortdal
authors: Sonia H
authors: SH
authors: Yoo
mesh_terms: D003319:Corneal Stroma / Q000648:ultrastructure*; D048988:Corneal Surgery, Laser / Q000379:methods*; D006801:Humans; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008855:Microscopy, Electron, Scanning; D009216:Myopia / Q000601:surgery*; D013499:Surface Properties; D013524:Surgical Flaps