Structural correlates of multidimensional visual dysfunction in Fuchs endothelial corneal dystrophy

To characterize the relationships between corneal morphological features and multiple domains of visual function in Fuchs endothelial corneal dystrophy (FECD), and to identify tomographic parameters reflecting functionally meaningful visual impairment.

Retrospective cross-sectional comparative study.

This study included 115 eyes with FECD and 85 control eyes. Assessments comprised best-corrected visual acuity, contrast sensitivity with and without glare, straylight, Scheimpflug tomography, anterior segment optical coherence tomography, and the Visual Function and Corneal Health Status questionnaire. The area under the log contrast sensitivity function (AULCSF) was calculated from five spatial frequencies. Associations between corneal parameters and AULCSF were examined using ordinary least squares regression and linear mixed-effects models with patient-level random intercepts.

FECD eyes showed reduced contrast sensitivity at all spatial frequencies after correction and increased straylight. Higher-order aberrations were greater in FECD eyes (0.70 ± 0.52 µm vs. 0.51 ± 0.30 µm, P<0.001). In mixed-effects models, the vertical coordinate of the thinnest point and the central-to-peripheral thickness ratio were associated with AULCSF under both nonglare and glare conditions, whereas posterior corneal depression was not independently associated after accounting for within-patient correlation. The pattern of associations with high-contrast visual acuity differed from that observed for AULCSF.

Visual impairment in FECD is domain-specific. Contrast sensitivity and straylight were more closely associated with localized corneal irregularity, pachymetric asymmetry, and higher-order aberrations than with global corneal edema. These findings indicate that visual dysfunction reflects multiple localized and asymmetric corneal changes, with no single dominant tomographic marker.