Use of an automated image analyser to quantitate cellular hyperplasia in urinary bladder epithelium.

The feasibility of using an automated image analyser to evaluate quantitatively hyperplasia caused by N-butyl-N-(4-hydroxybutyl) nitrosamine in bladder epithelium was studied. The number of cells per unit length of epithelium was counted manually, and compared with automated measurements of: (1) the number of nuclei, (2) the number of positive tangents to the lower edge of nuclei, (3) the nuclear cross-sectional area, and (4) the epithelial cross-sectional area per unit length respectively. Regression of each of the automated measurements on the manual counts all revealed close linear relationships with correlation coefficients in excess of 0-9. Coefficients of variation for repetitive automated measurements were less than or equal to 0-06 in each of the four modes. The automated system resulted in a great saving in time over manual counting. It is concluded that the automated image analyser provides an accurate, precise, and efficient tool for estimating epithelial cell numbers in normal and hyperplastic bladder epithelia.