title: Gamma-Irradiated Sterile Cornea for Use in Corneal Transplants in a Rabbit Model.
abstract: OBJECTIVE
  Gamma irradiated corneas in which the donor keratocytes and endothelial cells are eliminated are effective as corneal lamellar and glaucoma patch grafts. In addition, gamma irradiation causes collagen cross inking, which stiffens collagen fibrils. This study evaluated gamma irradiated corneas for use in corneal transplantations in a rabbit model comparing graft clarity, corneal neovascularization, and edema.
  
  
  METHODS
  Penetrating keratoplasty was performed on rabbits using four types of corneal grafts: Fresh cornea with endothelium, gamma irradiated cornea, cryopreserved cornea, and fresh cornea without endothelium. Slit lamp examination was performed at postoperative week (POW) one, two, and four. Corneal clarity, edema, and vascularization were graded. Confocal microscopy and histopathological evaluation were performed. A P < 0.05 was statistically significant.
  
  
  RESULTS
  For all postoperative examinations, the corneal clarity and edema were statistically significantly better in eyes that received fresh cornea with endothelium compared to the other three groups (P < 0.05). At POW 1, gamma irradiated cornea scored better than the cryopreserved and fresh cornea without endothelium groups in clarity (0.9 vs. 1.5 and 2.6, respectively), and edema (0.6 vs. 0.8 and 2.0, respectively). The gamma irradiated corneas, cryopreserved corneas and the fresh corneas without endothelium, developed haze and edema after POW 2. Gamma irradiated cornea remained statistically significantly clearer than cryopreserved and fresh cornea without endothelium during the observation period (P < 0.05). Histopathology indicated an absence of keratocytes in gamma irradiated cornea.
  
  
  CONCLUSIONS
  Gamma irradiated corneas remained clearer and thinner than the cryopreserved cornea and fresh cornea without endothelium. However, this outcome is transient. Gamma irradiated corneas are useful for lamellar and patch grafts, but cannot be used for penetrating keratoplasty.
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Junko
authors.initials: J
authors.lastname: Yoshida
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Heflin
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Zambrano
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Pan
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Huan
authors.initials: H
authors.lastname: Meng
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Jiangxia
authors.initials: J
authors.lastname: Wang
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Stark
authors.affiliation: Division of Cornea, Cataract, and External Disease, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors.forename: Yassine J
authors.initials: YJ
authors.lastname: Daoud
mesh_terms: D000818:Animals; D003094:Collagen / Q000378:metabolism; D003315:Cornea / Q000528:radiation effects*; D060527:Corneal Keratocytes / Q000502:physiology; D003432:Cross-Linking Reagents / Q000528:radiation effects; D015925:Cryopreservation; D004728:Endothelium, Corneal / Q000502:physiology; D005720:Gamma Rays; D006085:Graft Survival / Q000502:physiology; D015948:Keratoplasty, Penetrating; D008297:Male; D018613:Microscopy, Confocal; D009926:Organ Preservation / Q000379:methods*; D011817:Rabbits; D014019:Tissue Donors; D014184:Transplantation, Homologous
chemical_list: D003432:Cross-Linking Reagents; D003094:Collagen
keywords: Corneal Transplant; Gamma Irradiated Cornea; Sterile Cornea