title: Epi-laser in situ keratomileusis: comparative evaluation of epithelial separation with 3 microkeratomes.
abstract: OBJECTIVE
  To evaluate the cleavage plane, corneal cytoarchitecture, and cell vitality of separated corneal epithelial sheets created with 3 commonly used microkeratomes.
  
  
  METHODS
  Laboratories of the Regensburg University Medical Center, Regensburg, Germany.
  
  
  METHODS
  Mechanical separation of the epithelial layer in 10 porcine eyes and 2 human eyes was performed with 3 different microkeratomes (Amadeus II, Zyoptix XP, Epivision). Five of 10 porcine corneas and the 2 human corneas treated with each microkeratome were processed for histology, electron microscopy, and immunohistochemistry. In 5 of 10 porcine corneas, the corneal epithelial sheets were separated from the globe and cell vitality was assessed with the trypan blue dye vitality test.
  
  
  RESULTS
  A reproducible epithelial separation with a smooth surface was achieved in all eyes. The cleavage plane was located between the lamina lucida and the lamina densa. Damage to epithelial cells was mainly limited to the cut margins.
  
  
  CONCLUSIONS
  Mechanical separation of the epithelial sheet in epithelial laser in situ keratomileusis (epi-LASIK) was safe and reproducible with all evaluated microkeratomes. Immunohistochemistry and electron microscopy showed the cleavage plane in epi-LASIK was between the basal epithelium and the basement membrane at the level of the lamina lucida.
authors.affiliation: Department of Ophthalmology, Regensburg University Medical Center, Regensburg, Germany. herrmann@eye-regensburg.de
authors.forename: Wolfgang A
authors.initials: WA
authors.lastname: Herrmann
authors.forename: Jost
authors.initials: J
authors.lastname: Hillenkamp
authors.forename: Karsten
authors.initials: K
authors.lastname: Hufendiek
authors.forename: Philipp
authors.initials: P
authors.lastname: Prahs
authors.forename: Chris P
authors.initials: CP
authors.lastname: Lohmann
authors.forename: Horst
authors.initials: H
authors.lastname: Helbig
authors.forename: Karin
authors.initials: K
authors.lastname: Kobuch
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002470:Cell Survival; D024143:Collagen Type VII / Q000378:metabolism; D004396:Coloring Agents; D003315:Cornea / Q000601:surgery; D019573:Epithelium, Corneal / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D007124:Immunoenzyme Techniques; D039663:Integrin beta4 / Q000378:metabolism; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer; D013524:Surgical Flaps; D013552:Swine; D014343:Trypan Blue; D000097794:Kalinin
chemical_list: D015415:Biomarkers; D015815:Cell Adhesion Molecules; D024143:Collagen Type VII; D004396:Coloring Agents; D039663:Integrin beta4; D014343:Trypan Blue; D000097794:Kalinin