Quantification of the graphical details of collagen fibrils in transmission electron micrographs

A novel 2D image analysis technique is demonstrated. Using the digitized im ages of articular cartilage from transmission electron microscopy (TEM), th is technique performs a localized 'vector' analysis at each region that is large enough to include several or tens of collagen fibrils but small enoug h to provide a fine resolution for the whole tissue. For each small and loc alized region, the morphology of the collagen fibrils can be characterized by three quantities essential to the nature of the tissue: the concentratio n of the fibrils, the overall orientation of the fibrils, and the anisotrop y of the fibrils. This technique is capable of providing new insight to the existing technology by assigning quantitative attributes to the qualitativ e graphics. The assigned quantities are sensitive to the fine structure of the collagen matrix and meaningful in the architectural nature of the colla gen matrix. These quantities could provide a critical linkage between the u ltrastructure of the tissue and the macroscopic behaviours of the material. In addition, coarse-graining the microscopic resolution of EM without comp romising the essential features of the tissue's structure provides a direct view of the tissue's morphology and permits direct correlations and compar isons among interdisciplinary techniques.