Capabilities of Diffusion Spectroscopy with Spatial Resolution in Determining the Hydration and Parameters of the Microvasculature of Biotissues

The capabilities of spectroscopy with spatial resolution when determining the optical properties and parameters of the microvasculature of the circulatory system of surface tissues are demonstrated using specific examples of recording and processing the spectral-spatial profiles of local diffuse reflection of light by tissues of the human hand. The heterogeneity of tissue properties caused by individual distribution of vessels and chromophore concentration gradients at the investigated point of the body in addition to inadequacies of the used calculation model due to poorly studied absorption indices of the main chromophores of exsanguinated and dehydrated subcutaneous tissue are shown to contribute most to the scatter of the obtained results. A technique for recording spectral-spatial profiles and their two-stage processing is presented. Its capabilities and disadvantages are discussed. Prospective application of diffuse reflectance spectroscopy with spatial resolution to controlling the hydration of surface tissues during treatment of their inflammation and edema is shown.