title: "Top hat"-shaped penetrating keratoplasty using the femtosecond laser.
abstract: OBJECTIVE
  To determine the feasibility of using a modified femtosecond laser to perform penetrating corneal resections.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Fourteen corneoscleral rims were mounted on an artificial anterior chamber. Eight underwent traditional penetrating keratoplasty (PKP) and six underwent "top hat"-shaped PKP using a femtosecond laser. Wound leakage pressure and induced astigmatism were compared between the two groups.
  
  
  RESULTS
  Deep corneal resection with the femtosecond laser was feasible. Wound leakage occurred at 38 +/- 11 mm Hg in the traditional PKP eyes and at 240 +/- 69 mm Hg in the laser-shaped PKP groups. Initial induced astigmatism was 3.76 +/- 0.82 diopters and 3.46 +/- 1.36 diopters in the traditional and shaped PKP groups, respectively.
  
  
  CONCLUSIONS
  Shaped PKP using the femtosecond laser is feasible and provides superior incision integrity compared to traditional PKP. Initial induced astigmatism is dominated by suture effects.
authors: Department of Ophthalmology, University of California Irvine, California 92697, USA. steinert@uci.edu <steinert@uci.edu>
authors: Roger F
authors: RF
authors: Steinert
authors: Teresa S
authors: TS
authors: Ignacio
authors: Melvin A
authors: MA
authors: Sarayba
mesh_terms: D001082:Aqueous Humor / Q000378:metabolism; D001251:Astigmatism / Q000503:physiopathology; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D005240:Feasibility Studies; D006801:Humans; D007429:Intraocular Pressure; D015948:Keratoplasty, Penetrating / Q000379:methods*; D053685:Laser Therapy / Q000379:methods*; D013529:Surgical Wound Dehiscence / Q000503:physiopathology; D013536:Suture Techniques