COMPONENT QUANTITATION OF TISSUE SECTIONS. II. A STUDY OF THE FACTORS WHICH INFLUENCE THE ACCURACY OF THE METHOD

Abstract

The application of the component quantitators to computing the volume of various biologic materials has been verified by empiric experiments. Artificial mixtures of varying tissues, nuclear volume of liver (a homogeneous tissue), and islet volume of pancreas (component comprises only 1% of tissue) were studied. Experimental evidence is presented which indicates that the linear scan method is as accurate as paper weight or planimetry but the time required is one third less. Individual measurements are reproducible; they reflect the variation in proportion of wet weight of tissues included in artificial mixtures. From empiric data, the volume % of the component of interest, and the standard deviation, an equation may be applied to determine the number of mm. of scan necessary to obtain any desired degree of accuracy provided that the sampling of tissues is representative of the organ being studied. The total distance of scan required depends on the absolute size of the component being studied. When particles of the same size are scanned, the total distance of scan must be increased as the volume percentage of the component decreases. Where particles are of different size, the ratio (distance scanned divided by the mean particle size) must be increased as the % volume of component decreases. Where a component is distributed in more irregular fashion, this ratio must be increased also.