Interactive static image analysis: a major enhancement to histopathology and cytology

Recent developments in computerized data processing and digital video technology have made it possible to perform cytology and histopathology in quantitative as well as qualitative terms. The most common method for studying the DNA content of tumors in clinical laboratories is flow cytometry. The development of image analysis (IA) to study DNA content by Feulgen staining and microspectrophotometry actually preceded the development of flow cytometry, but the complexity of the method was so great that it never received widespread usage. In recent years computerized interactive static IA on microscope-based instruments has been developed. These instruments involve microscopy, a television camera and monitor, and a computer to analyze the data. They can be put together from separate components or are available as complete instrument packages from commercial companies. In addition to the study of DNA content, software is also available to perform quantitative immunoperoxidase determination and morphometry. These commercial instruments emphasize user-friendly software. Companies such as CAS (Cell Analysis Systems, Elmhurst, Illinois) provide operator training and annual user meetings. There is a growing interest among laboratories in bringing this technology into their institutions. This review will deal with the following aspects of IA: what it can do, how it works, what skills and training are required for an operator to use it, financial considerations, and how image cytometry compares to flow cytometry.