title: Endothelial cell studies in patients after photorefractive keratectomy for hyperopia.
abstract: OBJECTIVE
  To report central and peripheral corneal endothelial cell studies performed as part of the VISX hyperopic photorefractive keratectomy (PRK) clinical trial.
  
  
  METHODS
  During this prospective, multicenter clinical trial, which was part of an FDA investigation, endothelial cell specular microscopy was done at five centers. Non-contact central and peripheral cell density, percent hexagonality, and coefficient of variability of cell size were obtained using the Konan Noncon Robo SP-8000FA with BAMBI analysis software. Data were gathered at baseline and at 1, 6, and 12 months after hyperopic PRK.
  
  
  RESULTS
  Analysis of results of 171 eyes demonstrated no statistically significant detrimental changes in the corneal endothelium at any postoperative time point. The statistically significant changes noted were interpreted as an improvement in cell morphology and were attributed to the cessation of contact lens wear following treatment.
  
  
  CONCLUSIONS
  Hyperopic PRK with the VISX STAR S2 Excimer Laser System produced no statistically significant adverse effect on the corneal endothelium.
authors.affiliation: The Refractive Surgery Center, The Wilmer Eye Institute, The Johns Hopkins Hospital, Baltimore, MD, USA. nsjabbur@jhmi.edu
authors.forename: Nada S
authors.initials: NS
authors.lastname: Jabbur
mesh_terms: D000328:Adult; D000368:Aged; D002452:Cell Count; D048429:Cell Size; D004728:Endothelium, Corneal / Q000166:cytology*; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000601:surgery*; D054018:Lasers, Excimer; D008297:Male; D008853:Microscopy / Q000379:methods; D008875:Middle Aged; D018903:Photorefractive Keratectomy; D011446:Prospective Studies; D012029:Refraction, Ocular; D014792:Visual Acuity