A profile cannot be hidden behind another profile and thus not be identifiable.Precise prognostic and predictive variables allowing improved post-operative treatment stratification are missing in patients treated for stage II colon cancer (CC). Profiles of the same particle must be identifiable as being from the same particle in the 2 sections if present in the 2 sections. Q is the number of profiles selected on the reference section that is not present in the lookup section. All the profiles selected are then looked for in the lookup section. On 1 section, the reference section, a set of profiles are selected using the unbiased counting frame known area a. To use this technique, 2 parallel sections from the reference space are needed that are separated by a known distance h. The dissector principle is a technique that allows for unbiased estimation of Nv independent of particle size and shape.
A 3-D probe is the dissector (2 parallel sections a known distance apart). Therefore, one needs a 3-D probe to quantify particle number. Numerical denisty is the most difficult of the 4 parameters to measure from tissue sections.
The number of nuclei per unit volume of tumor. The number of glomeruli per unit volume of kidney. The number of mitochondria per unit volume of liver cell. Numerical density is the number of particles per unit volume of reference space. Divide by the sum of the total volumes of all sections: Take all the sections obtained from the cube and sum the volume of the particle over all the sections. The volume of the particle in a section is: Each section has a total area of at on each section face the particle has an area of ap. The cube is sliced parallel to the x, z, plane in thickness of t. The principle of Delesse is based on a cube containing only one component of irregular objects embedded in a matrix. Volume Density is defined as the volume of a component per unit volume of the containing reference space. In other words, as a ratio of at least two joint measurements, one relates to the components and the other relating to the structure as a whole. Profile- sharply defined flat trace of the section planeĪll stereological measurements are in principle obtained as relative measurements. Section- produced when plane intercepts a structure in 3 dimensional space Stereology- a body of mathematical calculations relating 3 dimensional parameters defining the structure to 2 dimensional measurements obtainable on sections of the structure The larger the sampling, the more precise an estimate can be.Īnother estimate of truth is accuracy. A characteristic of an estimate is a precision or degree of refinement of the measurement. Reallistically, we can only obtain an estimate of the truth. Truth may be obtained when the whole object is measured. Therefore, it is crucial to 'think 3-D' when imaging sections. A component that we may wish to study is usually a 3-dimensional object, but to view the component with the necessary resolution the shape is often lost.
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