title: Preliminary results after implantation of four AlphaCor artificial corneas.
abstract: OBJECTIVE
  The purpose was to evaluate the validity of implantation of the artificial cornea (AlphaCor) in human corneas considered too high risk for penetrating keratoplasty with donor tissue.
  
  
  METHODS
  Four keratoprostheses, made from poly(2-hydroxyethyl methacrylate) (PHEMA) with a porous skirt and a transparent optical part, were implanted into the cornea of four patients. Keratocytes invading the skirt provide a watertight fixation with the scarred corneal tissue. Deep to the clear optical part, the posterior corneal lamella was excised to a diameter of 3.5 mm before the device was implanted, and the anterior lamella was trephined similarly 3 months after AlphaCor implantation.
  
  
  RESULTS
  The eyes selected to receive an artificial cornea had significant neovascularisation, and 0-3 previous failed grafts. Follow-up for 6 months revealed best visual acuity between 20/400 and 20/50. Factors limiting the visual acuity outcome were optic atrophy and age-related macular disease. One patient underwent an extracapsular cataract extraction after the device was implanted, as a senile cataract was then noted. One complication occurred, a central corneal stromal melt, which was managed by covering with a 9-mm donor lamella.
  
  
  CONCLUSIONS
  The flexible device AlphaCor may provide a substitute for donor corneal tissue in desperate cases. Advantages include the simple implantation technique, which avoids trauma to the surrounding structures. Visual acuity results may be limited by pre-existing pathology, but it appears that a patient's visual potential can be achieved. Further follow-up to exclude long-term complications is required.
authors.affiliation: Eye Department of DRK Kliniken Westend, Spandauer Damm 130, 14050, Berlin, Germany. Prof.Dr.H.Bleckmann@t-online.de
authors.forename: H
authors.initials: H
authors.lastname: Bleckmann
authors.forename: S
authors.initials: S
authors.lastname: Holak
mesh_terms: D000328:Adult; D000368:Aged; D001187:Artificial Organs; D001672:Biocompatible Materials; D003315:Cornea; D003318:Corneal Opacity / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011102:Polyhydroxyethyl Methacrylate; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D014792:Visual Acuity
chemical_list: D001672:Biocompatible Materials; D011102:Polyhydroxyethyl Methacrylate