Corneal thickness and endothelial morphology in Normal Thai eyes

Background This study aimed to determine the influence of age on central corneal thickness and corneal endothelial morphology as well as to identify the relationship between them in normal Thai eyes. Methods Non-contact specular microscopy was performed in volunteers stratified into seven age groups ranging from 11 to 88 years. The corneal endothelial parameters studied included central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variation in cell size (CV), cell area (CA) and percentage of regular hexagonal cells. Results In a total of 501 subjects (1002 eyes), the mean age was 43.12 +/- 18.80 years and 347(69.3%) were females. The mean CCT, ECD, CV, CA, and hexagonality was 533.80 +/- 33.00 mu m, 2732 +/- 258 cell/mm(2), 37.61 +/- 6.76%, 369.04 +/- 37.90 mu m, and 49.03 +/- 7.53%, respectively. There was a significant inverse correlation between age and CCT (r = - 0.215, P < 0.001), ECD (r = - 0.496, P < 0.001),and hexagonality (r = - 0.265, P < 0.001). The CV and CA directly correlated with age (r = 0.242, P < 0.001 and r = 0.470, P < 0.001). The estimate rate of endothelial cell loss was 0.2% per year. There was no correlation between CCT and ECD (P = 0.106). Conclusion Normative data for corneal endothelial morphology in healthy Thai eyes showed that CCT, ECD, and hexagonality were significantly decreased, while the endothelial cell area and the variation in cell size were increased with aging. The central corneal thickness did not correlate with the endothelial cell density.