title: Split cornea transplantation: relationship between storage time of split donor tissue and outcome.
abstract: OBJECTIVE
  To analyze the relationship between storage time of split donor tissue and outcomes after deep anterior lamellar keratoplasty (DALK) and Descemet's membrane endothelial keratoplasty (DMEK).
  
  
  METHODS
  Retrospective analysis of a nonrandomized, consecutive, interventional case series.
  
  
  METHODS
  One hundred ten eyes with anterior stromal disease suitable for DALK and 110 eyes with endothelial disease suitable for DMEK underwent surgically successful split cornea transplantation combining both procedures within 7 days after splitting.
  
  
  METHODS
  Split donor storage times (splitting to grafting) and total storage times (death to grafting) were correlated with the 1-year functional and morphologic outcomes after DALK and DMEK surgery using a Spearman correlation coefficient and a Mann-Whitney U test.
  
  
  METHODS
  Best spectacle-corrected visual acuity (BSCVA), endothelial cell density, and complication rates within 12 months of follow-up.
  
  
  RESULTS
  The mean split donor storage time was 35 ± 47 hours (range, 0-162 hours) after splitting for anterior donor grafts and 21 ± 40 hours (range, 0-158 hours) for posterior grafts. The mean total storage time was 352 ± 108 hours (range, 108-678 hours) for anterior lamellas and 339 ± 109 hours (range, 96-630 hours) for posterior lamellas. One year after DALK, the mean BSCVA was 20/30 (range, 20/50-20/20), endothelial cell loss was 8% (range, 2%-16%), and the complication rate (Descemet's folds, epitheliopathy, loose sutures) was 18%. One year after DMEK, the mean BSCVA was 20/25 (range, 20/40-20/16), endothelial cell loss was 41% (range, 17%-63%), and the complication rate (partial graft detachment) was 62%. For DALK and DMEK, no significant association was observed between split donor storage time as well as total storage time and BSCVA (P ≥ 0.409), endothelial cell loss (P≥0.236), or complication rate (P ≥ 0.647) within 1 year of follow-up.
  
  
  CONCLUSIONS
  Anterior and posterior donor tissue may be stored safely for up to 1 week in organ culture before use in DALK and DMEK surgery. This simplifies the clinical feasibility of split cornea transplantation to reduce donor shortage and cost in corneal transplantation in the future.
  
  
  BACKGROUND
  The author(s) have no proprietary or commercial interest in any materials discussed in this article.
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany. ludwig.heindl@uk-koeln.de
authors: Ludwig M
authors: LM
authors: Heindl
authors: Stephan
authors: S
authors: Riss
authors: Werner
authors: W
authors: Adler
authors: Franziska
authors: F
authors: Bucher
authors: Deniz
authors: D
authors: Hos
authors: Claus
authors: C
authors: Cursiefen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003316:Corneal Diseases / Q000601:surgery*; D016039:Corneal Transplantation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D014021:Tissue Preservation / Q000592:standards*; D014792:Visual Acuity; D055815:Young Adult