Scoring of collagen organization in healthy and diseased human dermis by multiphoton microscopy

L.E.N.S. and Department of Physics, University of Florence, Sesto Fiorentino, Italy.
Journal of Biophotonics (Impact Factor: 3.86). 01/2009; 3(1-2):34-43. DOI: 10.1002/jbio.200910062
Source: PubMed

ABSTRACT 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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