Co-localized line-field confocal optical coherence tomography and confocal Raman microspectroscopy for three-dimensional high-resolution morphological and molecular characterization of skin tissues ex vivo

• Main Authors: Dubois, A. (Author), Ogien, J. (Author), Perrot, J.-L (Author), Waszczuk, L. (Author)
• Format: Article
• Language: English
• Published: Optica Publishing Group (formerly OSA) 2022
• Subjects: Biopsy; Colocalization; Confocal Raman microspectroscopy; Ex-vivo; High resolution; Histology; Line fields; Localised; Localization method; Molecular characterization; Morphological characterization; Optical tomography; Skin tissue; Tissue
• Online Access: View Fulltext in Publisher

 Line-field confocal optical coherence tomography (LC-OCT) is an optical modality that provides three-dimensional (3D) images of the skin at cellular resolution. Confocal Raman microspectroscopy (CRM) is a label-free optical technique that can provide point measurement of the molecular content of the skin. This work presents a method to co-localize LC-OCT and CRM acquisitions for morpho-molecular analysis of ex vivo skin tissues at cellular level. The co-localization method allows acquisition of Raman spectra at specific locations in a sample identified from a 3D LC-OCT image, with an accuracy of ± 20 µm. The method was applied to the characterization of tattooed skin biopsies with adverse tattoo reactions. LC-OCT images allowed to target specific regions in the biopsies where the presence of tattoo ink was revealed by detection of the Raman signature of ink pigments. Micrometer-sized foreign bodies of various materials as well as inflammatory cells were also identified within the biopsies. From these results, we demonstrate the value of the LC-OCT-CRM co-localization method and its potential for future ex vivo analysis of suspicious skin lesions. © 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement