LAUSR

Simple Summary The Flow Mediated Skin Fluorescence (FMSF) method, based on the observation of the fluorescence of nicotinamide adenine dinucleotide (NADH) coenzyme from skin tissue, allows for a non-invasive assessment of vascular circulation. The method characterizes dynamic changes in the NADH fluorescence caused by microcirculatory oscillations of endothelial, neurogenic or myogenic origin as well as those observed in response to the post-occlusive reactive hyperemia. It enables assessment of both vasoconstriction and vasodilation. The method defines three major parameters characterizing vascular circulation: reactive hyperemia response, hypoxia sensitivity and normoxia oscillatory index. The FMSF technique seems to be an optimal tool for characterizing macro- and micro-circulation status in a wide range of populations, from healthy physically active people to patients suffering from serious health problems related to vascular dysfunction. Abstract Flow Mediated Skin Fluorescence (FMSF) is a new non-invasive method for assessing vascular circulation and/or metabolic regulation. It enables assessment of both vasoconstriction and vasodilation. The method measures stimulation of the circulation in response to post-occlusive reactive hyperemia (PORH). It analyzes the dynamical changes in the emission of NADH fluorescence from skin tissue, providing the information on mitochondrial metabolic status and intracellular oxygen delivery through the circulatory system. Assessment of the vascular state using the FMSF technique is based on three parameters: reactive hyperemia response (RHR), hypoxia sensitivity (HS), and normoxia oscillatory index (NOI). The RHR and HS parameters determine the risk of vascular circulatory disorders and are the main diagnostic parameters. The NOI parameter is an auxiliary parameter for evaluating the state of microcirculation under stress of various origins (e.g., emotional stress, physical exhaustion, or post-infection stress). The clinical data show that the risk of vascular complications is limited among people whose RHR, log(HS), and NOI parameters are not significantly below the mean values determined by the FMSF technique, especially if they simultaneously meet the conditions RHR > 30% and log(HS) > 1.5 (HS > 30), and NOI > 60%.