A technique for section thickness evaluation for microphotometry and image analysis of sectioned nuclei

Area of Science:

• Histology
• Biomedical Imaging
• Molecular Biology

Background:

• Accurate DNA quantification in tissue sections is crucial for research and diagnostics.
• Precise determination of section thickness is a prerequisite for accurate DNA measurements.
• Existing methods for evaluating section thickness have limitations.

Purpose of the Study:

• To develop and validate a novel, reliable method for determining tissue section thickness.
• To provide a standardized approach for accurate DNA measurements in histological samples.

Main Methods:

• Preparation of celloidin cylinders stained with Periodic Acid-Schiff (PAS) reaction as thickness standards.
• Measurement of optical density of standard sections using microphotometry and image analysis.
• Determination of actual section thickness by re-embedding and transversal sectioning with a micrometric eyepiece.
• Creation of a normogram curve plotting optical density against actual thickness.

Main Results:

• A reproducible method for creating optical density standards of known thickness was established.
• A strong correlation between optical density and actual thickness of the standards was demonstrated.
• The developed normogram allows for accurate determination of unknown tissue section thickness based on optical density.

Conclusions:

• The novel method provides a reliable and accessible means to determine tissue section thickness.
• This technique facilitates accurate DNA measurements by enabling necessary corrections for section thickness.
• The use of PAS-stained celloidin cylinders offers a practical standard for histological applications.