ABSTRACT
PURPOSE: To document qualitative and quantitative changes in the normal, healthy human cornea with age using the confocal microscope. METHODS: The central corneas of 120 subjects (mean age, 41 years; range, 11 to 80 years) were examined using an in vivo slit-scanning real-time confocal microscope. Images of the corneal stroma and endothelium from both eyes of each subject were semiautomatically analyzed in an observer-masked, randomized manner. RESULTS: Anterior keratocyte density, posterior keratocyte density, and endothelial cell density were shown to be unaffected by the sex of the subject with p values of 0.46, 0.55, 0.50, respectively (multivariate analysis of variance). No statistically significant difference was detected between right and left eyes for all corneal layers examined. The anterior keratocyte density, posterior keratocyte density, and endothelial cell density decreased at a rate of 0.48, 0.22, and 0.33% per year, respectively. A positive correlation was found between the coefficient of cell variation and age. CONCLUSIONS: This data constitutes essential normative data that can be used as a control in further research into abnormal corneal conditions.
Subject(s)
Corneal Stroma/cytology , Endothelium, Corneal/cytology , Adolescent , Adult , Aged , Aged, 80 and over , Aging/physiology , Cell Count , Child , Double-Blind Method , Female , Fibroblasts/cytology , Humans , Male , Microscopy, Confocal , Middle AgedABSTRACT
The slit-scanning confocal microscope is a new clinical paradigm that allows the living human cornea to be viewed at a magnification of 680 x and a lateral resolution of 1 mum. As such, it allows corneal morphology to be inspected at a cellular level. The corneas of both eyes of 119 subjects who were evenly distributed in age from 10-80 years were examined using a Tomey ConfoScan P4 in-vivo slit-scanning real-time confocal microscope (Erlangen, Germany). Good quality representative images of the various corneal layers were selected for detailed qualitative analysis and are displayed here. A grid of corneal layer versus age was constructed from these images; this tool can be used as a normative confocal microscopy reference against which suspected corneal abnormalities can be assessed.
