Identification of topographical variations in the sizes of cells in a monolayer--application to corneal endothelium.
The cells in the corneal endothelium, do not have a constant geometric arrangement but rather can be organized into widely different patterns or arrays. Conventional statistical analyses of variance in cell size can be used to report that the endothelial mosaic is homogeneous (homomegethous) or heterogeneous (polymegethous) but do not identify the source of the homogeneity or its loss. We present methods that allow for both identification and graphical presentation of regional homogeneity or heterogeneity in the endothelial cell monolayer. Single electron micrographs (containing 180 cells) were taken at the central region of the rabbit corneal endothelium and cell areas measured by planimetry. Special computer programs allow progressive evaluation of variance in all cell areas across the set of cells. Several examples are presented in detail to illustrate different degrees and types of variance for sets of endothelial cells that have small to extremely large ranges of areas (i.e. coefficient of variation values ranging from 0.12 to over 1.0). There also appears to be a mathematically predictable relationship between cell surface area and the number of cell sides. The methods developed should be applicable to quantitative comparisons of cells in monolayers or tissue sections.
Doughty
M J
MJ
Univeristy of Waterloo, School of Optometry, Ontario, Canada.
Dilts
D M
DM
D000818:Animals; D048429:Cell Size / Q000502:physiology; D004728:Endothelium, Corneal / Q000166:cytology*; D005069:Evaluation Studies as Topic; D005260:Female; D008855:Microscopy, Electron, Scanning; D011817:Rabbits