Quantitative Assessment of Anteroposterior Keratocyte Density in the Normal Rabbit Cornea

Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas 75235-9057.
Cornea (Impact Factor: 2.04). 02/1995; 14(1):3-9. DOI: 10.1097/00003226-199501000-00002
Source: PubMed


The anteroposterior keratocyte density distribution in the rabbit cornea was measured. Unsectioned tissue blocks from the central cornea of five rabbits were stained with propidium iodide and imaged using a Leica laser scanning confocal microscope. A z-series of images was acquired confocal microscope. A z-series of images was acquired in each sample, from anterior to posterior stroma in either 3- or 8-microns steps. Software was developed to allow interactive marking of the keratocyte nuclei within each section of the z-series and for calculating cell density. For convenience, cell density was expressed as the number of cells per corneal volume element (CVE), where CVE is a newly defined volume unit with x, y, and z dimensions of 250, 250, and 10 microns, respectively. The calculated keratocyte density was 20.2 +/- 1.0 cells/CVE (n = 5), which is equivalent to 32,360 +/- 1,660 cells/mm3. The greatest density was underneath the epithelium (26.3 +/- 2.5 cells/CVE), the density then decreased linearly with depth to 15.2 +/- 1.4 cells/CVE; there was a slight increase in density pre-Descemets membrane to 18.5 +/- 3.5 cells/CVE. A 30% decrease in cell density over the entire anteroposterior stromal thickness was observed. To facilitate statistical analysis, the cell density was averaged over 5% thickness intervals from anterior to posterior cornea. A significant difference in mean cell density of these intervals was found (ANOVA, n = 20, p < 0.01). To further assess the density distribution, linear regression analysis was performed. A significant correlation was found between keratocyte density and stromal depth (R = -0.94, n = 20, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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