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Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens
Published on: January 24, 2016
Measuring strain using digital image correlation of second harmonic generation images.
Scott Wentzell1, Robert Sterling Nesbitt, James Macione
1Rensselaer Polytechnic Institute, Troy, NY, United States. wentzs@rpi.edu
Journal of Biomechanics
|July 13, 2013
Summary
A new method uses digital image correlation (DIC) with second harmonic generation microscopy (SHGM) to measure micrometer-level bone strains. This technique effectively captures strains within bone microarchitecture, aiding fracture and mechanobiology research.
Area of Science:
- Biomechanics
- Materials Science
- Cell Biology
Background:
- Understanding bone's micromechanical environment is vital for studying bone fracture and osteocyte mechanobiology.
- Existing techniques for measuring micrometer-scale strains in bone are limited.
Purpose of the Study:
- To develop and validate a novel method for measuring micrometer-level strains in bone tissue.
- To assess the effectiveness of digital image correlation (DIC) applied to second harmonic generation microscopy (SHGM) images for strain analysis.
Main Methods:
- Bovine tibia thin sections were subjected to mechanical loading (0 and 15 MPa).
- Second harmonic generation microscopy (SHGM) was used to image the bone sections.
- Digital image correlation (DIC) was applied to SHGM images to quantify micrometer-level strains.
Main Results:
- The developed DIC-SHGM technique effectively measured strains at the scale of bone microarchitecture.
- Strain measurements showed high heterogeneity, with significant variations across different regions.
- Analysis region size influenced strain magnitude, indicating tissue-level measurements for larger areas and a need for higher resolution for fibrillar strains.
Conclusions:
- The DIC-SHGM technique is a viable tool for studying the mechanical microenvironment of bone at the micrometer scale.
- The method shows potential for in vivo applications in small animal models.
- Further refinement is needed to achieve resolution for collagen fibrillar strain analysis.
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