title: Inverse mushroom-shaped nonmechanical penetrating keratoplasty using a femtosecond laser.
abstract: OBJECTIVE
  To demonstrate the feasibility of an inverse mushroom-shaped nonmechanical corneal trephination using a femtosecond laser in a noncontact manner.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  In this laboratory study, 10 polymethylmethacrylate (PMMA) blocks and 20 porcine corneas were treated with an industrial femtosecond laser source. The trephination profile consisted of (1) a 7- or 6-mm diameter cylinder from the anterior chamber, (2) an intermediate horizontal connecting plane, and (3) a concentric 5- or 4-mm diameter cylinder upwards.
  
  
  RESULTS
  Applying appropriate combinations of pulse energy and spacing, trephination took less than 60 seconds. In porcine eyes, light microscopy displayed trephination edges delineated by partly confluent gas bubbles (10-40 mum) with tissue bridges in between. By TEM, the cut edges were lined by a delicate, electron-dense layer (5-40 nm).
  
  
  CONCLUSIONS
  Femtosecond laser technology seems to offer a promising approach towards minimally invasive self-sealing "no-stitch keratoplasty."
authors.affiliation: Department of Ophthalmology, University of Erlangen-Nürnberg, Schwabachanlage 6, D-91054 Erlangen, Germany. berthold.seitz@augen.imed.uni-erlangen.de
authors.forename: Berthold
authors.initials: B
authors.lastname: Seitz
authors.forename: Holger
authors.initials: H
authors.lastname: Brünner
authors.forename: Arne
authors.initials: A
authors.lastname: Viestenz
authors.forename: Carmen
authors.initials: C
authors.lastname: Hofmann-Rummelt
authors.forename: Ursula
authors.initials: U
authors.lastname: Schlötzer-Schrehardt
authors.forename: Gottfried O H
authors.initials: GO
authors.lastname: Naumann
authors.forename: Achim
authors.initials: A
authors.lastname: Langenbucher
mesh_terms: D000363:Agaricales; D000818:Animals; D003315:Cornea / Q000601:surgery* / Q000648:ultrastructure; D005240:Feasibility Studies; D015948:Keratoplasty, Penetrating / Q000295:instrumentation / Q000379:methods*; D053685:Laser Therapy / Q000379:methods*; D019060:Minimally Invasive Surgical Procedures; D019904:Polymethyl Methacrylate; D013552:Swine
chemical_list: D019904:Polymethyl Methacrylate