title: Re-epithelialization in cornea organ culture after chemical burns and excimer laser treatment.
abstract: OBJECTIVE
  To describe the epithelial healing rates observed in freshly cultured rabbit corneas chemically burned with high-concentration hydrochloric acid (HCl) and sodium hydroxide (NaOH) and subsequently treated with phototherapeutic keratectomy (PTK).
  
  
  METHODS
  We obtained 126 fresh corneoscleral rims from cadaveric New Zealand white rabbits. Each cornea was exposed to 4-mm cellulose sponges soaked in a solution of topical 0.9% isotonic sodium chloride solution, 2M HCl, or 0.5M NaOH. A transepithelial PTK (6-mm zone; 100-microm ablation depth) was then performed using the excimer laser (150-mJ/cm(2) energy pulse; 20 nanosecond duration; and 10-Hz frequency). Corneas were placed in tissue culture, and 1 cornea from each group was taken out of culture each day after treatment. Re-epithelialization was monitored by means of fluorescein staining, slitlamp photography, and histopathological analysis.
  
  
  RESULTS
  Corneas treated with HCl and NaOH exhibited immediate epithelial defects that slowly healed over time. In PTK-treated corneas, the re-epithelialization rate was accelerated compared with that of controls (P =.003 for the HCl group, and P<.001 for the NaOH group). The new epithelial layers were smoother in PTK-treated corneas, as confirmed by results of histopathological analysis.
  
  
  CONCLUSIONS
  Corneal damage caused by HCl and NaOH may be modulated in vitro by PTK in this rabbit model.
  
  
  CONCLUSIONS
  After corneal chemical damage, 193-nm excimer laser PTK accelerates epithelial wound healing.
authors.affiliation: Department of Ophthalmology, University of California-Irvine, 2118 Med Surge I, Irvine, CA 92697, USA. rschuck@uci.edu
authors.forename: R S
authors.initials: RS
authors.lastname: Chuck
authors.forename: A
authors.initials: A
authors.lastname: Behrens
authors.forename: S
authors.initials: S
authors.lastname: Wellik
authors.forename: L L
authors.initials: LL
authors.lastname: Liaw
authors.forename: A M
authors.initials: AM
authors.lastname: Dolorico
authors.forename: P
authors.initials: P
authors.lastname: Sweet
authors.forename: L C
authors.initials: LC
authors.lastname: Chao
authors.forename: K E
authors.initials: KE
authors.lastname: Osann
authors.forename: P J
authors.initials: PJ
authors.lastname: McDonnell
authors.forename: M W
authors.initials: MW
authors.lastname: Berns
mesh_terms: D000818:Animals; D002057:Burns, Chemical / Q000378:metabolism* / Q000473:pathology; D003315:Cornea / Q000601:surgery; D065306:Corneal Injuries; D004847:Epithelial Cells / Q000502:physiology*; D019573:Epithelium, Corneal / Q000502:physiology*; D005126:Eye Burns / Q000139:chemically induced*; D015590:Fluorophotometry; D006851:Hydrochloric Acid; D054018:Lasers, Excimer; D009924:Organ Culture Techniques; D018903:Photorefractive Keratectomy; D011817:Rabbits; D012972:Sodium Hydroxide; D014945:Wound Healing
chemical_list: D012972:Sodium Hydroxide; D006851:Hydrochloric Acid