title: Quantitative assessment of anteroposterior keratocyte density in the normal rabbit cornea.
abstract: 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)
authors.affiliation: Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas 75235-9057.
authors.forename: W M
authors.initials: WM
authors.lastname: Petroll
authors.forename: K
authors.initials: K
authors.lastname: Boettcher
authors.forename: P
authors.initials: P
authors.lastname: Barry
authors.forename: H D
authors.initials: HD
authors.lastname: Cavanagh
authors.forename: J V
authors.initials: JV
authors.lastname: Jester
mesh_terms: D000818:Animals; D002452:Cell Count; D002467:Cell Nucleus; D003315:Cornea / Q000166:cytology*; D003319:Corneal Stroma / Q000166:cytology*; D004728:Endothelium, Corneal / Q000166:cytology*; D004847:Epithelial Cells; D007091:Image Processing, Computer-Assisted; D018613:Microscopy, Confocal / Q000379:methods; D011817:Rabbits