Regional variability in corneal endothelial cell density between guttae and non-guttae areas in Fuchs endothelial corneal dystrophy.

OBJECTIVE: To assess the regional variability of corneal endothelial cell density (ECD) between guttae and non-guttae areas in subjects with Fuchs endothelial corneal dystrophy (FECD) using non-contact specular microscopy and confocal microscopy.
DESIGN: Retrospective chart review from 2009 to 2014 at the Massachusetts Eye and Ear Infirmary. PARTICIPANTS: One hundred fifteen eyes of 73 subjects with FECD.
METHODS: Subjects with FECD underwent same-day specular and confocal microscopy in the same eye. Clinical stage of disease was documented on the day of image acquisition. Regional variability of ECD associated with guttae and non-guttae areas was assessed. Manual endothelial cell counts were performed.
RESULTS: Thirty-two percent of subjects had high quality endothelial images by both specular and confocal microscopy. Of these subjects, 83% were classified clinically as early-stage FECD. There was a significant association between stage of disease and the ability to obtain high quality specular images (χ2; p = 0.0012). There was no difference in mean ECD derived from specular (1363 ± 594 cells/mm2) or confocal (1391 ± 493 cells/mm2; p = 0.75) images. There was a statistically significant decrease of 31.8 ± 21.7% in mean ECD in areas surrounding guttae (1296 ± 560 cells/mm2) compared to non-guttae areas (1926 ± 674 cells/mm2; p < 0.0001) as determined by confocal microscopy.
CONCLUSION: These findings support confocal microscopy as an alternative to specular microscopy for evaluating the corneal endothelium of patients with FECD, especially those with advanced disease. Confocal microscopy also revealed regional differences in ECD in guttae and non-guttae areas in patients with FECD.