Tomographic Differences in Thin Corneas Following DMEK in Fuchs Dystrophy: A Case-Control Study

This study characterized the prevalence of thin corneas and identified tomographic patterns following Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial corneal dystrophy (FECD).

We conducted a retrospective observational study at a tertiary referral center, including 88 eyes with FECD treated by DMEK and an age- and sex-matched control group. Tomographic parameters such as central corneal thickness (CCT), pachymetric progression indices including Belin-Ambrosio D index (BAD-D), and anterior corneal asymmetry indices were analyzed using Scheimpflug imaging (Pentacam HR). Statistical analyses were performed to compare the DMEK and control groups and to examine correlations between clinical characteristics and CCT values.

At 1 year, the mean CCT in the DMEK group was 525 ± 36 µm, compared with 561 ± 32 µm in healthy controls (p < 0.001). Women were much more likely than men to have thin corneas (40% vs. 3.6% with CCT below 500 µm, p < 0.001) and higher BAD-D values (2.71 vs. 1.99, p = 0.007). In multivariate analysis, baseline CCT (β = -0.001, p < 0.001), age (β = -0.001, p = 0.032), and sex (β = 0.046, p < 0.001) were the strongest predictors of percentage pachymetric reduction, indicating that thicker preoperative corneas, older patients, and women experienced greater deswelling and thinner 1-year CCT. Postoperative endothelial cell density had no impact on pachymetry outcomes.

Patients with FECD undergoing DMEK often present with postoperative corneal thinning, particularly among women. Although the underlying cause is not fully understood, these findings suggest a potential link between chronic preoperative corneal edema and the likelihood of stromal remodeling. Further research is required to elucidate the mechanisms underlying this thinning phenomenon.