This study was conducted to describe corneal endothelial cell density and morphology in Malay eyes. Non-contact specular microscopy was performed in 125 eyes of 125 Malay volunteers, aged 20-87 years. Studied parameters included endothelial cell density (CD), mean cell area (MCA), coefficient of variation (CV) in cell area, as well as hexagonal appearance of the cells. Mean endothelial cell density in the study population was 2648 +/- 310 cell/mm(2). Mean CA, CV and percentage of hexagonal cells were 382.8 +/- 47.7microm(2), 58.1 +/- 22.6, 44.3% +/- 11.5% respectively. There was a statistically significant decrease in endothelial cell density (correlation - 0.300, P = 0.001) and CV in cell size (correlation - 0.208, P = 0.02) with age. There was a statistically significant increase in mean cell area (correlation 0.300, P = 0.001) with increasing age. The correlation between age and percentage of hexagonal cells was insignificant (correlation 0.074, P = 0.41). In conclusion, a consistent decrease was noted in the endothelial cell density with increasing age. The differences in endothelial cell density between genders were statistically insignificant.
PURPOSE: The aim was to assess the morphology of the Asian corneal endothelium, particularly the index of polymegethism and its relationship to endothelial cell density assessments.
METHODS: The central regions of the corneal endothelium of 72 healthy, normal weight, non-contact lens wearers were assessed by non-contact specular microscopy. There were six groups of persons, aged between 18 and 27 years, whose ethnic origins were self-reported as Asian (Mainland China, Hong Kong, India, Malaysia, Pakistan or other Asian groups). Single images including at least 100 contiguous cells were obtained from each subject and were processed by planimetry after manual border marking to minimise errors. Calculations were made of the coefficient of variation of cell area (COV; polymegethism) as well as the endothelial cell density and percentage of six-sided cells.
RESULTS: The COV values ranged from 18 to 30.4 per cent (group mean 24.5 ± 2.8 per cent). The corneas had essentially normal thickness (0.530 ± 0.026 mm), with the endothelia showing a high percentage of six-sided cells (66.3 ± 7.1 per cent) and none showing even mild signs of polymegethism. Endothelial cell density estimates based on average cell areas ranged from 2,020 to 3,623 cells per mm(2) and from 2,157 to 3,835 with calculations based on individual cell areas. The difference between the two estimates of endothelial cell density was strongly related to the coefficient of variation (r = 0.765).
CONCLUSIONS: This result is consistent with several older reports indicating that it is uncommon to find polymegethism in healthy young adult Asian individuals. Nonetheless, even low coefficient of variation values can substantially affect the estimations of the cell density.
KEYWORDS: Asian; cornea; endothelium; human; polymegathism