Identifying relationships between tomography-derived corneal thickness, curvature, and diameter and in vivo confocal microscopic assessment of the endothelium in healthy corneas of young adults

Abstract

Purpose Despite the importance of a healthy endothelial layer in anterior segment surgery, the possible influence of corneal parameters on endothelial cell density (ECD) has largely been ignored in the young adult eye. This study investigated the possible associations between corneal tomographic parameters and ECD values in young adults. Methods Subjects aged 21-30 years, with normal corneas were recruited. Mean ECD, mean cell area (MCA), coefficient of variation for cell area (COVA), and proportion of hexagonal cells were derived by in vivo confocal microscopy. The Orbscan II system was used to measure corneal parameters including: thickness, horizontal corneal diameter, corneal curvature, anterior and posterior elevation, and eccentricity. Results Sixty-two subjects (42 female, 20 male) were included (mean age 25±3 years). Overall mean ECD was 3169±309 cells/mm 2 with no differences between genders. Mean percentage of hexagonality was 53 ± 5%, male subjects (55%) had a higher percentage of hexagonal cells than female subjects (51%) (P ¼ 0.02). Central corneal thickness (CCT) was 529±43 lm. Central ECD was significantly correlated with CCT (Pearson's r ¼ 0.26, P ¼ 0.04). However, horizontal corneal diameter (r ¼ 0.19, P ¼ 0.14), anterior corneal curvature (r ¼ À0.07, P ¼ 0.6), and posterior corneal curvature (r ¼ À0.07, P ¼ 0.6) were not correlated with ECD or percentage of hexagonality. There was no statistically significant association between anterior chamber depth (3.6±0.3 mm) and ECD (r ¼ 0.15, P ¼ 0.3). Conclusion Corneal thickness is related to ECD in normal young adult eye, with lower ECD values identified in thinner corneas; however, corneal diameter and corneal curvature do not have a significant correlation with ECD.

Swelling of the Human Cornea Revealed by High-Speed, Ultrahigh-Resolution Optical Coherence Tomography

“…A third and related possibility is that the En-DM complex response is more dynamic than the biphasic changes observed in other layers. Last, central corneal thickness has been found to be related to the endothelial cell density in young, normal subjects, 58 and there is a reduction in endothelial cell density with age. 53 It may be that the between-subject variability is due to different endothelial cell densities across the various subjects' ages in our sample, leading to a variation in the endothelial pump capacity across the sample.…”

Age-related changes in central corneal thickness in normal eyes among the adult Lithuanian population

“…Referring to theory based on histologic studies, the corneas of older people are thinner because of a reduction in keratocyte density and possible destruction of collagen fibers, and senior individuals are exposed to environmental factors for a longer period of time, which might influence corneal structure 38. Hasemian et al demonstrated that corneal endothelial cell density decreases in persons until 60 years of age; however, the volume of these cells increases 39.…”

In vivo confocal microscopy of the corneal endothelium: comparison of three morphometry methods after corneal transplantation

“…Provided there are not too many errors, it should be fairly easy and not too time consuming to correct these cell border errors. 11,24,25,34 However, for the majority of grafts with non-uniform and large cells, this requires considerable time and is therefore largely impractical in a busy clinic. The automated option on the NAVIS software is substantially oversegmenting cell domains, thereby creating additional cell-cell borders at numerous locations across the ROI that are simply not present, resulting in an artificially high ECD.…”