A Compact Multi-Distance DCS and Time Domain NIRS Hybrid System for Hemodynamic and Metabolic Measurements

Abstract: In this work, we present a new multi-distance diffuse correlation spectroscopy (DCS)
device integrated with a compact state-of-the-art time domain near infrared spectroscopy (TD-NIRS)
device. The hybrid DCS and TD-NIRS system allows to retrieve information on blood flow, tissue
oxygenation, and oxygen metabolic rate. The DCS device performances were estimated in terms of
stability, repeatability, ability in retrieving variations of diffusion coefficient, influence of the tissue
optical properties, effect of varying count rates and depth sensitivity. Crosstalk between DCS and
TD-NIRS optical signals was also evaluated. Finally, in vivo experiments (venous and arterial cuff
occlusions on the arm) were conducted to test the ability of the hybrid system in measuring blood
flow variations.