利用近红外光谱检测多层组织血氧饱和度的研究

Near-Infrared Spectral Study on Blood Oxygen Saturation in Multilayer Tissue

利用近红外光谱无创检测生物组织血氧饱和状态,是一种极富研究和应用前景的检测技术,在临床检测中被广泛应用。但常规临床检测应用于指端仅反映局部血氧饱和度信息,在使用中具有局限性,信号的可信度也存在质疑。该文提出了一种采用反射式脉搏血氧饱和度检测技术检测生物多层组织氧合状况的新方法,该方法通过调节入射光强以适应解剖学中生物组织多层结构的检测。应用该方法针对手指结构的实验结果表明,随着入射光强的改变,反映血氧饱和状态的光电脉搏波信号有显著变化。结合手指解剖学分析表明,光电脉搏波信号的变化与手指的多层面组织结构相对应,反映不同层面血氧饱和状态。这一特点表明,通过此法可以针对生物组织的多层结构进行测量。

The technology of non-invasive near-infrared spectral detection of biological tissue blood oxygen saturation has great research and application prospects,and has widespread clinical applications. However,the conventional finger oximeter only reflects local oxygen saturation values,and has limitations in the application. These oxygenation readings become unreliable or cease,too. In the present paper,a new method is described that the reflectance pulse oximetry with variable incident light intensity is employed to measure biological multilayer tissue. The photoplethysmographic （PPG） signals significantly change with the change in the incident light intensity in the experiment on the fingertip. Further analysis shows that the changes of the PPG signals correspond to the multilayer structure of finger. It means that the blood oxygen saturation of different tissue level must be calculated from the PPG signals. These features show that this method must be feasible.