title: [Influence of 20 % sulfur hexafluoride (SF6) on human corneal endothelial cells : An in vitro study].
abstract: BACKGROUND
  In posterior lamellar keratoplasties, such as Descemet membrane endothelial keratoplasty (DMEK) and Descemet's stripping automated endothelial keratoplasty (DSAEK) an air bubble is left inside the anterior chamber to promote graft attachment during the early postoperative period. In the case of insufficient graft adhesion a renewed intracameral air injection is often necessary. The use of sulfur hexafluoride diluted with air (SF6 20 %) as an alternative to pure air may further enhance graft attachment and reduce the rebubbling rate. The effect of SF6 20 % on corneal endothelium is currently unclear and was therefore examined in vitro.
  
  
  METHODS
  For this study 12 human corneoscleral discs were mounted in artificial anterior chambers, the systems were continuously filled with culture medium and the anterior chambers with air (n = 5) or SF6 20 % (n = 7) as tamponade. After 6 days of storage in the incubator endothelial cell density, toxicity on endothelial cells and corneal thickness were evaluated.
  
  
  RESULTS
  There were no significant differences in endothelial cell loss (p = 1.000), endothelial cell count (p = 0.648), toxicity on endothelial cells (p = 0.048) and central corneal thickness (p = 0.905) between the two groups after 1 week. The level of significance was defined as p ≤ 0.05 and adjusted to p ≤ 0.0056 according to the Bonferroni correction for multiple testing.
  
  
  CONCLUSIONS
  The use of SF6 20 % as tamponade in the anterior chamber for posterior lamellar keratoplasty can be proposed as a safe alternative to pure air filling related to endothelial cell loss. Increased toxic effects on the corneal endothelium by SF6 20 % were not detected in this study; however, further prospective clinical trials are needed to examine the long-term effects in humans.
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland. friederike.schaub@uk-koeln.de.
authors.forename: F
authors.initials: F
authors.lastname: Schaub
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland.
authors.forename: H G
authors.initials: HG
authors.lastname: Simons
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Roters
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland.
authors.forename: L M
authors.initials: LM
authors.lastname: Heindl
authors.affiliation: Gesellschaft für hochreine Biomaterialien, FLUORON GmbH, Ulm, Deutschland.
authors.forename: W
authors.initials: W
authors.lastname: Kugler
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland.
authors.forename: B O
authors.initials: BO
authors.lastname: Bachmann
authors.affiliation: Zentrum für Augenheilkunde, Universitätsklinikum Köln, Kerpener Straße 62, 50924, Köln, Deutschland.
authors.forename: C
authors.initials: C
authors.lastname: Cursiefen
mesh_terms: D000368:Aged; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D055954:Corneal Endothelial Cell Loss / Q000139:chemically induced / Q000473:pathology / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D004728:Endothelium, Corneal / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013459:Sulfur Hexafluoride / Q000008:administration & dosage* / Q000737:chemistry / Q000633:toxicity
chemical_list: D013459:Sulfur Hexafluoride
keywords: Cornea; Corneal endothelium; Fuchs' endothelial dystrophy; Keratoplasty; Transplant