title: Preliminary evaluation of a hydrogel core-and-skirt keratoprosthesis in the rabbit cornea.
abstract: BACKGROUND
  We developed a core-and-skirt keratoprosthesis, with both components made from poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogels. The identical chemical nature of both spongy skirt and transparent core assures a permanent union between them. We have previously shown that PHEMA sponges, within a certain range of pore size, can support cellular invasion and neovascularization when implanted into the rabbit cornea. The present study is the first to evaluate the behavior of the whole prosthesis after implantation into the rabbit cornea.
  
  
  METHODS
  Hydrogel keratoprostheses were inserted intrastromally into the corneas of seven rabbits and histologically examined by light microscopy in five eyes enucleated at 8, 12, and 14 weeks.
  
  
  RESULTS
  None of the implants extruded over this period. Both clinical and histopathologic examination showed that the keratoprostheses were well tolerated by the host tissue. The porous skirt was fully integrated into the stroma by fibrovascular invasion, and no capsule formed around the implants. Stromal melting anterior to the implant occurred in two cases, but this did not affect the fixation of the keratoprostheses.
  
  
  CONCLUSIONS
  This study indicates that our keratoprosthesis can prevent extrusion in the short term when inserted into an intrastromal pocket of the rabbit eye.
authors.affiliation: Lions Eye Institute, Perth, Australia.
authors.forename: G J
authors.initials: GJ
authors.lastname: Crawford
authors.forename: T V
authors.initials: TV
authors.lastname: Chirila
authors.forename: S
authors.initials: S
authors.lastname: Vijayasekaran
authors.forename: P D
authors.initials: PD
authors.lastname: Dalton
authors.forename: I J
authors.initials: IJ
authors.lastname: Constable
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D005069:Evaluation Studies as Topic; D005500:Follow-Up Studies; D011102:Polyhydroxyethyl Methacrylate; D019736:Prostheses and Implants; D011817:Rabbits
chemical_list: D001672:Biocompatible Materials; D011102:Polyhydroxyethyl Methacrylate