Coherent optical processing of cervical cytologic samples.

Abstract

Earlier research using a very limited data base gave encouraging results for the automated screening of exfoliated cytologic samples using coherent optical processing techniques to examine individual isolated cells. A more thorough investigation involving a larger data base has confirmed our initial results. This investigation was performed using a specially designed Fourier spectrum analyzer and a solid state optical detector array. An analysis was made to determine the performance of a screening system using such a cell-by-cell discriminating device. This analysis indicated that less than 20,000 cells would have to be examined to obtain a system performance level of 1% false negative and 10% false positive error rates with a 1% probability of occurrence of malignant cells in a malignant sample. This performance figure was inferred from measured statistical performance characteristics of a laboratory cell-by-cell screening device using optically generated Fourier transfrom techniques for cell discrimination. The performance of the system was shown to be much more sensitive to cell-by-cell false error rates than false negative error rates. It was also found that the majority of false positive errors were due to misclassifying parabasal cells as malignant. By eliminating parabasal cells, which comprised more than 25% of our normal cell data base, the number of cells needed to be screened dropped by an order of magnitude. It was also shown that there is an inverse quadratic relationship between the percentage of malignant cells in a malignant sample and the number of cells that must be screened to achieve any desired system performance.