Determining the specific stages at which visual impairment occurs during the course of Fuchs’ endothelial corneal dystrophy (FECD) could help steer clinical strategies toward vision-preserving interventions. This study examined patients with FECD using tomography to detect various levels of severity and compared the features to patients’ vision parameters.
Study design
This was a cross-sectional study performed at the Mayo Clinic. Patients with a range of FECD severity levels and those with normal corneas were identified. Eyes were included if they were pseudophakic with a monofocal posterior chamber intraocular lens, and excluded if they had clinically visible edema. All eyes were evaluated for high-contrast visual acuity (HCVA), photopic and mesopic low-contrast visual acuity (LCVA), and straylight testing. All patients also underwent visual disability assessment using a survey and Pentacam testing to identify 3 features of subclinical edema.
Outcomes
In FECD without any Pentacam features of edema, the authors found that HCVA, LCVA, and straylight did not significantly differ from normal corneas across the full range of guttae severity. On the other hand, in cases of FECD with all 3 Pentacam features of subclinical edema, HCVA, LCVA, and straylight were worse as compared with normal corneas. Similarly, patient-reported disability in the form of subjective visual acuity and glare were significantly worse when all 3 features of subclinical edema were present as compared to normal corneas. Finally, HCVA, mesopic LCVA, straylight, and self-reported glare were worse in FECD with 1 or 2 tomographic abnormalities compared with normal.
Limitations
The primary limitation of this study was the small sample size (61 FECD eyes and 17 healthy eyes). A second shortcoming of the study was that it did not include a prospective assessment of changes in vision in eyes over time, as longitudinal fluctuations may have taken place.
Clinical significance
Tomographic patterns of edema in patients with FECD was associated with poorer vision. This finding highlights the growing value of tomography in the assessment of patients with FECD, and the role it can play in clinical decision-making. Tomography can help clinicians to recognize when FECD will likely not function as the etiology for visual disability, and therefore when surgical intervention should be deferred.