Computerized interactive morphometry of brushing cytology specimens.

Forty-two bronchial brushing cytology specimens were evaluated by a video-based computerized interactive morphometry (CIM) system with an interactive peripheral consisting of a touch-sensitive screen mounted over a high-resolution video monitor. The system was programmed to allow a trained observer to rapidly measure nuclear and cytoplasmic profile diameters of randomly selected cells and to calculate their nuclear-cytoplasmic ratios. The specimens included 13 cytologic slides with no malignant cells present, 14 with non-small cell carcinoma cells and 15 with small cell carcinoma cells. The cases were divided into two groups: a training set composed of slides with "known diagnosis" and a test set of slides with "unknown diagnosis". A data set was constructed with the measurements from the cases with "known diagnosis," and an algorithm that allowed the classification of cases by hierarchical analysis was developed. The data was also analyzed with statistical methods of classificatory discriminant analysis. Utilizing the information in the data base, the slides with "unknown diagnosis" were classified individually; all cases were correctly classified by the procedures. Potential applications of CIM in cytology are discussed.