Quantification of cells in a three-dimensional (3-D) structure requires estimates based on unbiased principles. Studies using two-dimensional methods (2-D) to report data of 3-D structures are still frequently used, however, these methods do not consider the heteroge-neous nature of the structure in terms of shape and distribution of cells. Consequently they make assumptions about the 3-D structure of interest and the results do not refer to the complete structure. These limitations reduce the sensitivity and accuracy of the methods as well as increase the risk of errors. However, this can be avoided by the application of de-sign-based stereology. Stereology is based on a set of statistical and mathematical princi-ples and provides efficient tools for estimation of volume, surface area, length, and number of objects in 3-D structures by sampling in 2-D sections.
Because stereology relies on statistical sampling principles and stochastic geometric theory, the methods guarantee that no biases are introduced to the analysis and allow one to ob-tain, in principle, accurate and precise quantitative data on structural changes in tissue sec-tions. Generally stereology includes sampling principles that ensures statistically valid sampling of sections from a complete structure, using a minimum of tissue for analysis and without reducing the precision of the estimate. A set of suitable probes are then superim-posed on the sections in a uniform random order, and the number of relevant objects with-in the probes is determined. This results in counts with a known mathematical relation to the total quantity in 3-D. Because of the statistical sampling principles and mathematical basis of the probes no bias is introduced when sections or probes are chosen for 3-D analy-sis.
In this special volume most of the papers will focus on the application of different stereo-logical methods and their practical aspects. The methods have been applied to structures in the central nervous system using a number of stereological techniques that will be intro-duced and explain by certified stereologists. This allows new scientists to consider the ap-plication of these methods on their own studies.
Quantification of cells in a three-dimensional (3-D) structure requires estimates based on unbiased principles. Studies using two-dimensional methods (2-D) to report data of 3-D structures are still frequently used, however, these methods do not consider the heteroge-neous nature of the structure in terms of shape and distribution of cells. Consequently they make assumptions about the 3-D structure of interest and the results do not refer to the complete structure. These limitations reduce the sensitivity and accuracy of the methods as well as increase the risk of errors. However, this can be avoided by the application of de-sign-based stereology. Stereology is based on a set of statistical and mathematical princi-ples and provides efficient tools for estimation of volume, surface area, length, and number of objects in 3-D structures by sampling in 2-D sections.
Because stereology relies on statistical sampling principles and stochastic geometric theory, the methods guarantee that no biases are introduced to the analysis and allow one to ob-tain, in principle, accurate and precise quantitative data on structural changes in tissue sec-tions. Generally stereology includes sampling principles that ensures statistically valid sampling of sections from a complete structure, using a minimum of tissue for analysis and without reducing the precision of the estimate. A set of suitable probes are then superim-posed on the sections in a uniform random order, and the number of relevant objects with-in the probes is determined. This results in counts with a known mathematical relation to the total quantity in 3-D. Because of the statistical sampling principles and mathematical basis of the probes no bias is introduced when sections or probes are chosen for 3-D analy-sis.
In this special volume most of the papers will focus on the application of different stereo-logical methods and their practical aspects. The methods have been applied to structures in the central nervous system using a number of stereological techniques that will be intro-duced and explain by certified stereologists. This allows new scientists to consider the ap-plication of these methods on their own studies.