Near-infrared spectroscopy has been used for measurement of changes in cerebr al Hb concentrations in infants to study cerebral oxygenation and hemodynamics. In this study, measurements by time-resolved spectroscopy (...Near-infrared spectroscopy has been used for measurement of changes in cerebr al Hb concentrations in infants to study cerebral oxygenation and hemodynamics. In this study, measurements by time-resolved spectroscopy (TRS) were performed in 22 neonates to estimate the values of light absorption coefficient and reduce d scattering coefficient (μ’s), cerebral Hb oxygen saturation (Sco2), cerebral blood volume (CBV), and differential path-length factor (DPF), and the relatio nships between postconceptional age and μ’s, Sco2, CBV, and DPF were investigated. A portable three-wavelength TRS system with a probe attached to the head of the neonate was used. The mean μ’s values at 761, 795, and 835 nm in neonates were estimated to be (mean ±SD ) 6.46 ±1.21, 5.90 ±1.15 and 6.40 ±1.16/cm, respectively. There was a signifi cant positive relationship between postconceptional age and μ’s at those three wavelengths. The mean Sco2 value was calculated to be 70.0 ±4.6%, and postcon ceptional age and Sco2 showed a negative linear relationship. The mean value of CBV was 2.31 ±0.56 mL/100 g. There was a significant positive relationship betw een postconceptional age and CBV. The mean DPF values at 761, 795, and 835 nm we re estimated to be 4.58 ±0.41, 4.64 ±0.46, and 4.31 ±0.42, respectively. Ther e was no relationship between postconceptional age and DPF at those three wavele ngths. The results demonstrated that our near-infrared TRS method can be used t o monitor μ’s, Sco2, CBV, and DPF in the neonatal brain at the bedside in an i ntensive care unit.展开更多
文摘Near-infrared spectroscopy has been used for measurement of changes in cerebr al Hb concentrations in infants to study cerebral oxygenation and hemodynamics. In this study, measurements by time-resolved spectroscopy (TRS) were performed in 22 neonates to estimate the values of light absorption coefficient and reduce d scattering coefficient (μ’s), cerebral Hb oxygen saturation (Sco2), cerebral blood volume (CBV), and differential path-length factor (DPF), and the relatio nships between postconceptional age and μ’s, Sco2, CBV, and DPF were investigated. A portable three-wavelength TRS system with a probe attached to the head of the neonate was used. The mean μ’s values at 761, 795, and 835 nm in neonates were estimated to be (mean ±SD ) 6.46 ±1.21, 5.90 ±1.15 and 6.40 ±1.16/cm, respectively. There was a signifi cant positive relationship between postconceptional age and μ’s at those three wavelengths. The mean Sco2 value was calculated to be 70.0 ±4.6%, and postcon ceptional age and Sco2 showed a negative linear relationship. The mean value of CBV was 2.31 ±0.56 mL/100 g. There was a significant positive relationship betw een postconceptional age and CBV. The mean DPF values at 761, 795, and 835 nm we re estimated to be 4.58 ±0.41, 4.64 ±0.46, and 4.31 ±0.42, respectively. Ther e was no relationship between postconceptional age and DPF at those three wavele ngths. The results demonstrated that our near-infrared TRS method can be used t o monitor μ’s, Sco2, CBV, and DPF in the neonatal brain at the bedside in an i ntensive care unit.