Assessment of microvascular function using near-infrared spectroscopic 2D imaging of whole hand combined with vascular occlusion test

[object Object]Near-infrared spectroscopy (NIRS) is an optical technique able to assess blood oxygen saturation (StO2) non-invasively. StO2 of peripheral blood (blood contained in small vessels in strict contact with tissue cells) reflects the adequacy of blood flow and O2 supply for tissue metabolism. Recent studies have tested the clinical utility of NIRS for studying peripheral microcirculation with the use of a NIRS probe, exploring a limited portion of hand skin (generally the thenar eminence), combined with vascular occlusion testing (VOT). In order to gain information from much larger tissue areas, the present study evaluates the possibility of using a NIRS two-dimensional (2D) camera for whole-hand imaging. Twelve healthy adults were tested. A NIRS camera was used to acquire the hemoglobin StO2 2D mapping of the whole-hand inner surface during VOT. Several parameters were calculated from the StO2 trend obtained from the NIRS image set, using two exemplifying regions of interest on the thenar eminence and the middle finger.