Learning Curve in Descemet's Membrane Endothelial Keratoplasty: First Series of 135 Consecutive Cases

Ophthalmology. 2011 Nov;118(11):2147-54. doi: 10.1016/j.ophtha.2011.03.037. Epub 2011 Jul 20.

Abstract

Purpose: To evaluate the learning curve in Descemet's membrane endothelial keratoplasty (DMEK) in the management of corneal endothelial disorders.

Design: Retrospective, nonrandomized, clinical study at a tertiary referral center.

Participants: 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.

Main outcome measures: 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.

Financial disclosure(s): Proprietary or commercial disclosures may be found after the references.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cell Count
  • Cell Survival
  • Clinical Competence
  • Descemet Stripping Endothelial Keratoplasty*
  • Endothelium, Corneal / pathology
  • Female
  • Fuchs' Endothelial Dystrophy / physiopathology
  • Fuchs' Endothelial Dystrophy / surgery*
  • Humans
  • Intraoperative Complications
  • Learning Curve*
  • Male
  • Middle Aged
  • Postoperative Complications
  • Retrospective Studies
  • Tissue Donors
  • Tomography, Optical Coherence
  • Treatment Outcome
  • Visual Acuity / physiology