Purpose: To describe Descemet's membrane endothelial keratoplasty (DMEK) techniques, perioperative challenges, management, and visual and refractive outcomes.
Design: Prospective, multicenter, consecutive case series.
Participants: Sixty eyes of 56 patients with Fuchs' endothelial dystrophy, pseudophakic bullous keratopathy, or failed previous graft.
Intervention: Descemet's membrane (DM) and endothelium were stripped from donor corneas submerged in corneal storage solution in a corneal viewing chamber. Donor DM diameters were 8.5 or 9.0 mm. The central 7 mm of DM was stripped from the recipient cornea. After staining with trypan blue to improve visualization, donor DM was inserted through a 2.8-mm incision. Descemet's membrane endothelial keratoplasty was performed alone (n = 48) or was combined with phacoemulsification and lens implantation (n = 11), pars plana vitrectomy (n = 2), or both.
Main outcome measures: Best spectacle-corrected visual acuity (BSCVA), manifest refraction, and endothelial cell density.
Results: Median BSCVA was 20/30 at 1 month (range, 20/20-20/60), improving from 20/50 (range, 20/25-hand movements) before DMEK, excluding 4 eyes (7%) with preexisting ocular pathologic features that limited visual potential. At 3 months, 26% had 20/20 vision, 63% saw 20/25 or better, and 94% saw 20/40 or better. Refractive cylinder remained unchanged at 0.9 diopters (D; P = 0.93), and a hyperopic shift of 0.49+/-0.63 D (P = 0.0091) was noted in DMEK single procedures. Endothelial cell loss was 30%+/-20% at 3 months and 32%+/-20% in 38 eyes that reached the 6-month examination. Median pachymetry decreased from 660 mum before surgery to 530 mum. Descemet's membrane stripped successfully from 60 of 72 donor corneas; 6 were converted successfully to Descemet's stripping automated endothelial keratoplasty (DSAEK) and 6 (8%) were discarded. Only 1 graft detached completely, but air was reinjected in 38 eyes (63%), mainly for partial detachments. Five DMEK corneas (8%) failed to clear and were replaced successfully with DMEK or DSAEK. All remained clear at last follow-up.
Conclusions: Compared with DSAEK, DMEK provided a significantly higher rate of 20/20 and 20/25 vision, with comparable endothelial cell loss. Descemet's membrane endothelial keratoplasty restored physiologic pachymetry, but donor preparation and attachment currently are more challenging than with DSAEK.