Scoring of collagen organization in healthy and diseased human dermis by multiphoton microscopy. J. Biophoton. 3, 34-43

L.E.N.S. and Department of Physics, University of Florence, Sesto Fiorentino, Italy.
Journal of Biophotonics (Impact Factor: 4.45). 09/2009; 3(1-2):34-43. DOI: 10.1002/jbio.200910062
Source: PubMed


We have used nonlinear imaging to evaluate collagen organization in connective tissue ex-vivo samples. Image analysis methods were tested on healthy dermis, normal scars, and keloids. The evaluation of the second harmonic to autofluorescence aging index of dermis (SAAID) has allowed a first characterization of tissues by scoring the collagen/elastin content. Further analyses on collagen morphology in healthy dermis and keloids were performed by image-pattern analysis of SHG images. The gray-level co-occurrence matrix (GLCM) analysis method has allowed classification of different tissues based on the evaluation of geometrical arrangement of collagen fibrillar bundles, whereas a pattern analysis of the FFT images has allowed the discrimination of different tissues based on the anisotropy of collagen fibers distribution. This multiple scoring method represents a promising tool to be extended to other collagen disorders, as well as to be used in in-vivo skin-imaging applications.

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Available from: Dimitrios Kapsokalyvas, Oct 05, 2014
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    • "Experimental techniques providing volume 3D images of the collagen structure of tissues do already exist in the literature. For example, we note the multiphoton fluorescence microscopy techniques [6] [7] [8], which have the advantage to avoid any preparation of the sample for the observation of collagen due to its autofluorescence. "
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    • "Some collagen classification metrics that are discussed in the skin aging section, also find applications in wound healing. Cicchi et al. also assessed three different approaches, including employing a gray-level co-occurrence matrix (which was studied further by Ferro et al.170), a fast Fourier transform and a measure known as the SAAID, or Second-harmonic Autofluorescence Aging Index of Dermis.142 Rather than determining one superior technique, it was found that each was effective at a particular length scale. "
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