In vivo measure of neonate brain optical properties and hemodynamic parameters by time-domain near-infrared spectroscopy.

By exploiting a multichannel portable instrument for time-domain near-infrared spectroscopy (TD-NIRS), we characterized healthy neonates' brains in term of optical properties and hemodynamic parameters. In particular, we assessed the absolute values of the absorption and reduced scattering coefficients at two wavelengths, together with oxy-, deoxy- and total hemoglobin concentrations, and the blood oxygen saturation of the neonates' brains. In this study, 33 healthy full-term neonates were tested, obtaining the following median values: 0.28 and [Formula: see text] for [Formula: see text] at 690 and 820 nm, respectively; 5.8 and [Formula: see text] for [Formula: see text] at 690 and 820 nm, respectively; [Formula: see text] for [Formula: see text]; [Formula: see text] for [Formula: see text]; [Formula: see text] for [Formula: see text]; 72% for [Formula: see text]. In general, the agreement of these values with the sparse existing literature appears not always consistent. These findings demonstrate the first measurements of optical properties of the healthy neonate brain using TD-NIRS and show the need for clarification of optical properties across methods and populations.