Stratum corneum (SC) biomarkers such as its thickness and hydration level offer valuable information about the state of the skin barrier. A Fourier domain visible light optical coherence tomography (VIS-OCT) system with an axial resolution of ~1 μm in tissue, was used to assess the morphology of the human SC layer under different hydration conditions. 12 human subjects (7 males, 5 females) in an age group of 21-59 were recruited. B-scan images of subjects’ dorsal hands were recorded by the VIS-OCT system and processed in MATLAB and GraphPad. An average SC thickness in the dorsal area before hydration, after hydration in water for 40 minutes and after drying in air for 40 minutes were found to be: 9 μm ± 0.1 μm, 19 μm ± 0.2 μm and 8 μm ± 0.1 μm, correspondingly. SC reflectance, obtained by VIS-OCT, changes at different hydration levels, increasing in a range of |4-12|dB during the hydration phase and decreasing in a range of |4-13|dB during the dehydration phase. That SC reflectance data correlates moderately to strongly, depending on an individual, with SC hydration levels measured by a Corneometer.
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