Basic study on measurement of quantitative cerebral hemoglobin concentration using the full spectrum near infrared spectroscopy

脑血流动力学和氧合功能的实时监测对新生儿脑损伤的预防和治疗具有重要意义。我们以前报道过，使用全光谱近红外光谱(FsNIRS)，通过指数校正方程将平坦和非线性扩散光谱转换为非平坦和线性的透射谱，并对各个光谱之间的不同光路长度进行多分量最小二乘曲线拟合，然后进行归一化。在本研究中，我们开发了一种新的分析系统，它可以用光学光谱测量半定量的脑血红蛋白浓度和脑血管饱和度。在体外实验中，我们发现了显著的相关性(r=0.895，p&lt；用我们的新方法测得的总血红蛋白浓度与时间分辨光谱分析(1%脂内溶液中的血红蛋白浓度为0.0001~81.4MHb)之间的差值为0.0001。在新生仔猪体内换血实验中，两种方法测定的脑总血红蛋白浓度与血红蛋白饱和度之间也有显著的相关性(r=0.944，p&lt；0.0001；r=0.858，p&lt；0.0001)，并与体外结果进行了比较。我们所称的基团与时间分辨光谱所确定的光程长度有很好的关系。因此，我们认为比较不同受试者的数值是可能的。

Real-time measurement of cerebral hemodynamics and oxygenation are very important for the prevention and management of brain damage in neonates. We have previously reported, using the full spectrum near infrared spectroscopy (fsNIRS), conversion of the flattened and nonlinear diffusion spectra to the non flattened and linear transmission spectra by exponential correction equation, and multi-component least square curve fitting and then normalization of different light path-lengths among individual spectra.In this study, we have developed a new analytical system, which allows optical spectroscopic measurements of semiquantitative cerebral hemoglobin concentration and cerebrovasucular saturation.In vitro experiment, we found a significant correlation (r = 0.895, p < 0.0001) between total hemoglobin concentration obtained by our new methods and this measured by time resolved spectroscopy (0 〜 81.4 μM of hemoglobin concentration in 1% intralipid solution). In vivo experiments of blood exchange transfusion in newborn piglets, significant correlations (r = 0.944, p < 0.0001 ; r = 0.858, p < 0.0001 respectively) among the respect cerebral total hemoglobin concentration and the respect hemoglobin saturation determined by the two methods were also observed as well as the result in vitro. The base which we call had a good relationship with optical path length determined by time resolved spectroscopy. Therefore, we consider that it is possible to compare the values obtained from different subjects.