[High resolution cell recognition and flow cytometry as means to automated cytodiagnosis]

Measurement and quantification are the prerequisites of automated cell diagnosis. The goal of the analysis is to recognize quantitative differences for the classification of benign and malignant cells. Absorption and fluorescence dyes can be bound to definite cell components proportional to their amounts and can be determined photometrically. In static photometry the cells are spread out in a single layer on a glass slide. By examining the cell point by point a scanning image can be obtained. These high resolution photometric measurements provide many individual data on relatively few cells. In flow photometry the cells are suspended in a fluid. The fluid flows past the lens of the microscope. Because each cell remains in front of the lens for only a brief period, it is possible to detect only one or few parameters per cell. These zero or low resolution flow photometric procedures provide few individual data on a great number of cells. Hybrid procedures combine flow photometry with subsequent high resolution photometry of the individual cell. To make this possible suspicious cells are sorted out from the flowing fluid and deposited on a slide. In individual cases the efficiency of visual diagnosis is almost achieved by machines.