Central Corneal Thickness 6 Postoperative Months After Pseudophakic-Descemet Membrane Endothelial Keratoplasty, Triple-Descemet Membrane Endothelial Keratoplasty, and Cataract Surgery Alone: A Retrospective Cohort Study and Literature Review

PURPOSE: Descemet membrane endothelial keratoplasty (DMEK) is the gold standard treatment for Fuchs endothelial corneal dystrophy (FECD). It is generally conducted mo/yr or immediately after lens phacoemulsification (pseudophakic-DMEK and triple-DMEK, respectively). A recent meta-analysis reported that mean central corneal thickness (CCT) 6 to 12 months after pseudophakic/triple-DMEK in Western European patients was 522 μm. However, mean CCT in healthy Western Europeans is 552 μm. This retrospective cohort study tested whether post-DMEK CCT in FECD eyes is thinner than normal by comparing consecutive pseudophakic/triple-DMEK eyes to consecutive cataract-surgery control eyes. METHODS: The 3 groups from a French hospital were compared for ultrasonic pachymetry-measured preoperative and 6-month postoperative CCT. To identify predictive factors for 6-month post-DMEK CCT drop, multivariable analysis with age, sex, preoperative CCT, preoperative visual acuity, and DMEK group was performed. RESULTS: The pseudophakic-DMEK, triple-DMEK, and cataract-control groups (n = 61 each) did not differ in age or sex. Preoperative and 6-month CCT in cataract-surgery controls were both 550 μm. CCT dropped after pseudophakic-DMEK (619-526 μm, P < 0.001) and triple-DMEK (614-529 μm, P < 0.001) and was significantly lower at 6 months than in cataract-surgery controls (both P < 0.001). On multivariable analysis, only preoperative CCT predicted post-DMEK CCT drop (parameter estimate = 0.87 ± 0.06, P < 0.001). CONCLUSIONS: Both pseudophakic-DMEK and triple-DMEK associated with thinner 6-month postoperative CCT than cataract-surgery controls. This may reflect residual fibrosis from FECD that compacts the corneal stroma after DMEK-induced deturgescence. This was supported by our finding that greater preoperative CCT, a potential marker of severe FECD/fibrosis, predicted thinner postoperative CCT.