Distribution of Particles in the Z-axis of Tissue Sections: Relevance for Counting Methods

Area of Science:

• Stereology
• Histology
• Biomedical Imaging

Background:

• Accurate particle counting in thick tissue sections is vital for stereology.
• Artifacts such as lost caps and z-axis deformation can compromise section integrity.
• Previous assumptions underestimated the prevalence of differential z-axis deformation.

Purpose of the Study:

• To investigate artifacts affecting particle distribution in the z-axis of thick tissue sections.
• To identify the causes and characteristics of z-axis deformation.
• To provide insights for improving stereological counting methods.

Main Methods:

• Analysis of particle distribution in the z-axis across different sectioning methods and embedding media.
• Assessment of differential deformation in paraffin, glycolmethacrylate, vibratome, celloidin, and cryostat sections.
• Distinguishing primary (sectioning-induced) and secondary (lost caps) artifacts through distortion patterns.

Main Results:

• Differential z-axis deformation is a common artifact, dependent on embedding media and sectioning devices.
• Paraffin, glycolmethacrylate, and vibratome sections are susceptible, unlike celloidin or cryosections.
• Z-axis deformation, likely caused by sectioning compression, leads to differential particle densities.

Conclusions:

• Z-axis deformation and lost caps are significant artifacts in thick tissue sections.
• Understanding these artifacts is essential for accurate stereological analysis, particularly with methods like the optical disector.
• Proper assessment and mitigation strategies are needed to minimize bias in particle counting.