In vivo multiphoton microscopy associated to 3D image processing for human skin characterization

Abstract

International audienceMultiphoton microscopy has emerged in the past decade as a promising non-invasive skin imaging technique. The aim of this study was to assess whether multiphoton microscopy coupled to specific 3D image processing tools could provide new insights into the organization of different skin components and their age-related changes. For that purpose, we performed a clinical trial on 15 young and 15 aged human female volunteers on the ventral and dorsal side of the forearm using the DermaInspectR medical imaging device. We visualized the skin by taking advantage of intrinsic multiphoton signals from cells, elastic and collagen fibers. We also developed 3D image processing algorithms adapted to in vivo multiphoton images of human skin in order to extract quantitative parameters in each layer of the skin (epidermis and superficial dermis). The results show that in vivo multiphoton microscopy is able to evidence several skin alterations due to skin aging: morphological changes in the epidermis and modifications in the quantity and organization of the collagen and elastic fibers network. In conclusion, the association of multiphoton microscopy with specific image processing allows the three-dimensional organization of skin components to be visualized and quantified thus providing a powerful tool for cosmetic and dermatological investigations

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Computational and experimental characterization of skin mechanics: identifying current challenges and future directions

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The skin‐depigmenting potential of Paeonia lactiflora root extract and paeoniflorin: in vitro evaluation using reconstructed pigmented human epidermis

“…Endogenous chromophores such as NAD(P)H, flavins, keratin, melanin or elastin create 2PEF signals, whereas SHG signals are obtained from dense, non-centro-symmetrical, and ordered macromolecular structures such as fibrillar collagen. This technique has already been applied for characterizing normal skin, age-related or photo-ageing skin changes [23][24][25][26][27], dermatological disorders and melanoma [28,29], as well as in cosmetic and pharmaceutical research [21,22,30].…”