title: Myofibroblast metaplasia after descemet membrane endothelial keratoplasty.
abstract: OBJECTIVE
  To describe myofibroblastic metaplasia of corneal endothelial cells in 2 cases with impaired visual function despite complete graft adherence after Descemet membrane endothelial keratoplasty (DMEK).
  
  
  METHODS
  Interventional case series.
  
  
  METHODS
  In 2 of 90 consecutive DMEK surgeries, the cornea failed to clear up to 6 months postoperatively despite complete graft attachment. After secondary penetrating keratoplasty, both corneal buttons were examined using histopathologic analysis and transmission electron microscopy.
  
  
  RESULTS
  Light microscopy revealed distinct corneal endothelial cell attenuation with the presence of an abnormal posterior collagenous layer in both cases. Most of the remaining endothelial cells had an elongated fibroblast-like appearance with immunopositivity for α-smooth muscle actin indicative of myofibroblast metaplasia. Transmission electron microscopy showed a slightly thickened Descemet membrane with an abnormal posterior fibrillar collagenous layer and a myofibroblast-like transformation of the remaining endothelial cells. Descemet membrane grafts closely adjoined the collagen lamellae of the host corneal stroma similar to the Descemet membrane-stroma interface of a normal cornea.
  
  
  CONCLUSIONS
  Myofibroblastic metaplasia of attenuated corneal endothelial cells with formation of an abnormal posterior collagenous layer may contribute to an impaired visual function despite complete graft adherence after Descemet membrane endothelial keratoplasty (DMEK).
authors: Department of Ophthalmology and Eye Hospital, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, Erlangen, Germany. ludwig.heindl@uk-erlangen.de
authors: Ludwig M
authors: LM
authors: Heindl
authors: Ursula
authors: U
authors: Schlötzer-Schrehardt
authors: Claus
authors: C
authors: Cursiefen
authors: Bjoern O
authors: BO
authors: Bachmann
authors: Carmen
authors: C
authors: Hofmann-Rummelt
authors: Friedrich E
authors: FE
authors: Kruse
mesh_terms: D000199:Actins / Q000378:metabolism; D000368:Aged; D015715:Corneal Edema / Q000601:surgery; D003319:Corneal Stroma / Q000648:ultrastructure; D003886:Descemet Membrane / Q000648:ultrastructure; D057111:Descemet Stripping Endothelial Keratoplasty; D004728:Endothelium, Corneal / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006084:Graft Rejection / Q000209:etiology* / Q000601:surgery; D006801:Humans; D015948:Keratoplasty, Penetrating; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D058628:Myofibroblasts / Q000378:metabolism / Q000473:pathology*; D011183:Postoperative Complications; D014786:Vision Disorders / Q000209:etiology
chemical_list: C541116:ACTA2 protein, human; D000199:Actins