title: Learning Curve in Descemet's Membrane Endothelial Keratoplasty: First Series of 135 Consecutive Cases.
abstract: OBJECTIVE
  To evaluate the learning curve in Descemet's membrane endothelial keratoplasty (DMEK) in the management of corneal endothelial disorders.
  
  
  METHODS
  Retrospective, nonrandomized, clinical study at a tertiary referral center.
  
  
  METHODS
  We included 135 eyes of 118 patients with Fuchs' endothelial dystrophy.
  
  
  METHODS
  In a first group of 135 consecutive eyes, a DMEK was performed. To determine the extent of a possible learning curve in DMEK surgery, the whole group was divided into 3 subgroups of 45 patients, to compare clinical outcomes at 1, 3, and 6 months.
  
  
  METHODS
  Best-corrected visual acuity (BCVA), endothelial cell density (ECD), and intra- and postoperative complications.
  
  
  RESULTS
  Among the 3 groups clinical outcomes were similar, with 73% of cases achieving a BCVA of ≥20/25 (≥0.8) and an average ECD of 1747 ± 527 cells/mm², at 6 months. Graft detachment was the main complication and correlated with intraoperative vitreous pressure (P<0.01). The detachment rate declined with experience: In the first 45 cases, a complete or partial graft detachment occurred in 20%, in the second group in 13.3%, and in the third group in 4.4%. Other complications were relatively uncommon: Failure to unfold or position the graft during surgery (0.7%), intraocular hemorrhage (0.7%), primary graft failure (2.2%), air-bubble induced angle closure glaucoma (3%), remnant host Descemet's at the interface (5.9%), and cystoid macular edema (0.7%). Surgeries (partially) performed by an inexperienced surgeon showed a similar clinical outcome and complication rate.
  
  
  CONCLUSIONS
  The learning curve in DMEK did not correlate with clinical outcome (BCVA and ECD), but rather to the presence of a functional graft. However, the number of functional grafts (decline in graft detachment rate) increased with surgical experience.
  
  
  BACKGROUND
  Proprietary or commercial disclosures may be found after the references.
authors.affiliation: Netherlands Institute for Innovative Ocular Surgery, Rotterdam, The Netherlands.
authors.forename: Isabel
authors.initials: I
authors.lastname: Dapena
authors.forename: Lisanne
authors.initials: L
authors.lastname: Ham
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Droutsas
authors.forename: Korine
authors.initials: K
authors.lastname: van Dijk
authors.forename: Kyros
authors.initials: K
authors.lastname: Moutsouris
authors.forename: Gerrit R J
authors.initials: GR
authors.lastname: Melles
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002452:Cell Count; D002470:Cell Survival; D002983:Clinical Competence; D057111:Descemet Stripping Endothelial Keratoplasty; D004728:Endothelium, Corneal / Q000473:pathology; D005260:Female; D005642:Fuchs' Endothelial Dystrophy / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007431:Intraoperative Complications; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012189:Retrospective Studies; D014019:Tissue Donors; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology