Line-field confocal optical coherence tomography as a tool for three-dimensional in vivo quantification of healthy epidermis: a pilot study.

Epidermal three-dimensional (3D) topography/quantification have not been completely characterized yet. The recently developed line-field confocal optical coherence tomography (LC-OCT) provides real-time, high-resolution, in-vivo 3D imaging of the skin. This pilot study aimed at quantifying epidermal metrics [epidermal thicknesses, dermal-epidermal junction (DEJ) undulation and keratinocyte number/shape/size] using 3D LC-OCT. For each study participant (8 female, skin-type-II, younger/older volunteers), seven body sites were imaged with LC-OCT. Epidermal metrics were calculated by segmentations and measurements assisted by artificial intelligence (AI) when appropriate. Thicknesses of epidermis/SC, DEJ undulation and keratinocyte nuclei volume varied across body sites. Evidence of keratinocyte maturation was observed in vivo: keratinocyte nuclei being small/spherical near the DEJ and flatter/elliptical near the skin surface. Skin microanatomy can be quantified by combining LC-OCT and AI. This technology could be highly relevant to understand ageing processes and conditions linked to epidermal disorders. Future clinical/research applications are to be expected in this scenario. This article is protected by copyright. All rights reserved.