title: Evaluation of broadband spectral transmission characteristics of fresh and gamma-irradiated corneal tissues.
abstract: OBJECTIVE
  The aim of this study was to evaluate the clarity of gamma-irradiated sterile corneal donor lenticules.
  
  
  METHODS
  Broadband UV, visible, and near-infrared (200-850 nm) light transmission was measured through gamma-irradiated, sterile partial-thickness, and full-thickness donor lenticules and fresh corneal tissues and compared with standard acrylic intraocular lens (IOL) implants using a conventional spectrophotometer technique.
  
  
  RESULTS
  All tissues had high light transmission (≥ 90%) in the visible and near-infrared regions and very low (<2%) transmission below 290 nm. Differences in light transmission between irradiated and fresh cornea types were observed between 300 and 450 nm, which mirrored differences in light transmission through their respective storage solutions. Light transmission through partial-thickness irradiated donor lenticules was greatest across all wavelengths. All corneal tissues exhibited higher transmission than acrylic IOL implant across all wavelengths.
  
  
  CONCLUSIONS
  Gamma-irradiated donor lenticules are comparable with fresh corneas regarding light transmission, with both partial-thickness and full-thickness lenticules having greater transmission than standard IOL. We would expect the optical performance of gamma-irradiated donor lenticules to be comparable to fresh cornea if used for lamellar corneal procedures that do not require a viable endothelium.
authors.affiliation: *Optical Therapeutics and Medical Nanophotonics Lab, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD; †Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA; ‡The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD; and §Office of Device Evaluation, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD.
authors.forename: William R
authors.initials: WR
authors.lastname: Calhoun
authors.forename: Esen K
authors.initials: EK
authors.lastname: Akpek
authors.forename: Richard
authors.initials: R
authors.lastname: Weiblinger
authors.forename: Ilko K
authors.initials: IK
authors.lastname: Ilev
mesh_terms: D003315:Cornea / Q000502:physiology* / Q000528:radiation effects*; D005720:Gamma Rays; D006801:Humans; D007259:Infrared Rays; D008027:Light; D009926:Organ Preservation; D013056:Spectrophotometry, Ultraviolet; D019265:Spectroscopy, Near-Infrared; D013242:Sterilization / Q000379:methods; D014019:Tissue Donors; D014466:Ultraviolet Rays