The Dynamics of Optical and Physiological Characteristics of Human Skin in vivo during Its Compression

Resumo

The results of the study of the dynamics of optical and physiological properties of skin upon exposure to and removal of external mechanical compression, based on the analysis of temporal changes in diffuse reflectance spectra of human skin in vivo in the range of 400–2000 nm, are presented. In the spectral region of 500–600 nm (hemoglobin absorption region), the temporal dynamics of skin reflectance indicates that the skin compression causes an exponential decrease in the amount of blood in it, with an average time of blood displacement from the compression area of approximately 4–5 min. After compression removal, the skin blood filling exponentially recovers approximately within 30 s. In the spectral region of 700–2000 nm, skin reflectance after compression monotonically decrease according to two-exponential law with characteristic times of approximately 10 s and several minutes, which may be determined by the displacement of free and bound water from the compression area.