Diurnal Changes In Best-Corrected Visual Acuity And Corneal Parameters In Fuchs Endothelial Corneal Dystrophy

To evaluate diurnal changes in clinical, topographic and specular microscopic parameters in patients with Fuchs Endothelial Corneal Dystrophy (FECD).

This study was conducted at İzmir City hospital and patients followed with Fuchs endothelial dystrophy during June 2024 and June 2025 were included in the study.

Thirty-three patients diagnosed with FECD and 44 eyes were included, along with 33 healthy patients matched for age and gender. Patients were staged according to the Krachmer classification. Parameters were measured at three different time points in all participants: baseline (T0), first time point (T1), and second time point (T2). Best corrected visual acuity (BCVA), intraocular pressure (IOP), pachymetric measurements, specular microscopy, topography, single-session OCT measurements for glaucoma, and a single-session gonioscopic examination with iridocorneal angle measurement. Statistical analyses employed linear mixed-effects models and nested linear mixed-effects models. The significance level was set at p < 0.05.

Visual acuity in the FECD group showed statistically significant changes over time, whereas no significant changes were observed in the control group. In the intergroup comparison, visual acuity values in the FECD group were found to be significantly lower than those in the control group at all time points (p < 0.001). Although no significant difference was observed between the groups in terms of intraocular pressure, statistically significant changes were observed over time in the FECD group. No significant differences were found between the groups in terms of anatomical parameters (axial length, anterior chamber depth, and iridocorneal angle).  

FECD is essentially a progressive dystrophy limited to the corneal endothelium, and measurements taken at a single point in time may not be sufficient for clinical evaluation. The stage of the disease and temporal changes should be evaluated together. Regular follow-up is particularly important in the early stages.