Noninvasive imaging of human skin hemodynamics using a digital red-green-blue camera

摘要

In order to visualize human skin hemodynamics, we investigated a method that is specifically developednfor the visualization of concentrations of oxygenated blood, deoxygenated blood, and melanin in skin tissuenfrom digital RGB color images. Images of total blood concentration and oxygen saturation can also be reconstructednfrom the results of oxygenated and deoxygenated blood. Experiments using tissue-like agar gel phantomsndemonstrated the ability of the developed method to quantitatively visualize the transition from an oxygenatednblood to a deoxygenated blood in dermis. In vivo imaging of the chromophore concentrations and tissue oxygennsaturation in the skin of the human hand are performed for 14 subjects during upper limb occlusion at 50 andn250 mm Hg. The response of the total blood concentration in the skin acquired by this method and forearmnvolume changes obtained from the conventional strain-gauge plethysmograph were comparable during the uppernarm occlusion at pressures of both 50 and 250 mm Hg. The results presented in the present paper indicate thenpossibility of visualizing the hemodynamics of subsurface skin tissue.