Purpose: To report the mid-term outcomes of hemi-Descemet membrane endothelial keratoplasty (hemi-DMEK) performed for Fuchs endothelial corneal dystrophy (FECD).
Methods: In this prospective, interventional case series, we evaluated clinical outcomes of 10 eyes from 10 patients who underwent hemi-DMEK for FECD. Main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density (ECD), central pachymetry, and postoperative complications.
Results: At 1 year postoperatively, 7/7 eyes (excluding 2 eyes with low visual potential) reached a BCVA of ≥20/40 (≥0.5), 6/7 (86%) ≥20/25 (≥0.8), 4/7 (57%) ≥20/20 (≥1.0), and 2/7 (29%) 20/17 (≥1.2). BCVA remained stable until 2 years postoperatively (P ≥ 0.05) and further improved thereafter (P < 0.05). Mean ECD decreased from 2740 (±180) cells/mm preoperatively to 850 (±300) cells/mm (n = 9) at 1 year (P ≤ 0.05) and showed an annual decrease of on average 6% to 7% thereafter (P ≥ 0.05 between consecutive follow-ups). Pachymetry decreased from preoperatively 745 (±153) μm to 533 (±63) μm (n = 9) and 527 (±35) μm (n = 8) at 1 and 3 years postoperatively, respectively. Within the first 6 postoperative months, 4/10 eyes underwent rebubbling for visually significant graft detachment. One eye received secondary circular DMEK for persistent graft detachment 1 month postoperatively; another eye developed secondary graft failure 2.5 years postoperatively, and 1 eye was suspected for an allograft reaction 1.5 years postoperatively.
Conclusions: Hemi-DMEK may render visual outcomes comparable to those achieved by conventional DMEK. Despite low ECD counts by 6 months, ECD levels remain fairly stable thereafter. Hence, hemi-DMEK may become a potential alternative technique for treatment of FECD while increasing the yield of the endothelial tissue pool.