Development of stereological analysis software for the calculation of volume, number and surface density.
COSAS, an acronym for COmputerized Stereological Analysis System, is software designed to facilitate the process of quantitative morphological analysis. It is a flexible, reliable, and easy to use software system which provides the biologist with a simple means for performing stereological analysis. It provides for estimation of volume and surface density and allows for direct calculation of diameter information from planimetric data. The latter capability is unique to COSAS and provides the ability to calculate longest and shortest diameters for convex profiles, enabling calculation of number density. Access to all intermediate calculations is possible, so the process of transformation of raw data into the stereological descriptors can be completely exposed. This serves two purposes: (1) it provides a means for tracing results; (2) the intermediate values can be utilized independently. This system was used to analyze peroxisomes in tissues from patients with Zellweger's disease and neonatal-onset adrenoleukodystrophy. The system was also used to facilitate an immunocytochemical analysis of cytochrome P450 topology in the endoplasmic reticulum membrane.