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Descemet Membrane Endothelial Keratoplasty (DMEK) in Previously Vitrectomized Eyes: Complications and Clinical Outcomes.

PURPOSE
To evaluate the results and complications of Descemet membrane endothelial keratoplasty (DMEK) in previously vitrectomized eyes.


DESIGN
Retrospective study of 35 eyes that had undergone DMEK, due to Fuchs endothelial corneal dystrophy (FECD), at our department with a follow-up after 6 months postoperatively. We compared the intraoperative procedure, complications, and results of DMEK between 14 previously vitrectomized pseudophakic eyes (group 1) and a control group of 21 pseudophakic non-vitrectomized eyes (group 2).


RESULTS
The unfolding time (in minutes) was significantly longer in group 1 than in group 2 (10.5 ± 6.4 vs. 3.2 ± 1.5, p < 0.01). A single re-bubbling was needed in 8 patients in group 1 (57.1%) and in 3 patients in group 2 (14.2%) (p < 0.01). Repeated re-bubbling (≥ 1 time) was performed in only 5 patients of group 1 (35.7%). There was significant postoperative improvement in best-corrected visual acuity (BCVA, in LogMAR) in both groups (p = 0.04 in group 1 and p < 0.01 in group 2). The central corneal thickness (CCT, in µm) did not differ significantly between the two groups preoperatively (p = 0.4) or postoperatively (p = 0.1). However, the CCT decreased significantly postoperatively in both groups (p < 0.01 in both groups). The postoperative endothelial cell density (ECD in cell/mm²) was significantly lower in group 1 than in group 2 (p = 0.03).


CONCLUSION
DMEK in previously vitrectomized eyes presents a surgical challenge, which requires special, and sometimes unpredictable, intraoperative maneuvers, but good functional and morphological results can be achieved. The use of the endothelial Descemet membrane lamellae (EDML) of older donors might be recommended to facilitate the intraoperative unfolding process.