Development of noninvasive measurement of peripheral circulation and its application for health care

最近，利用光敏传感器和发光二极管（LED），可以无创地测量动脉血氧饱和度、手指动脉压和数字动脉弹性。光传感器也被用于测量数字动脉的机械性能和指标，如外周组织的血容量。使用激光光束和LED近红外光获得了各种外周血循环指标。虽然这些指标可以通过施加短期压力无创或微创获得，但当施加袖带压力时，测量的连续性就丧失了。在这种方法中，仅使用一个波长的光进行测量是不够的。如果使用两个波长，可以改进绝对值的测定。我们还对使用光传感器评估外周循环功能进行了初步研究。建立了测量仪器、测量原理、评估手指动脉的弹性和非线性特性、测量组织血容量。

Recently, it has become possible to noninvasively measure the oxygen saturation level of arterial blood, finger arterial pressure, and the elasticity of digital arteries using photosensors and light-emitting diodes(LED). Photosensors have also been used to measure the mechanical properties of digital arteries and indices such as the blood volume in peripheral tissue.There are various peripheral circulatory indices that was obtained using a laser beam and near infrared light from LED. Though these indices can be obtained noninvasively or minimally invasively by application of short-term pressure, the continuity of measurement is lost when cuff pressure is applied. Measurement is insufficient using light of only 1 wavelength in this method. Determination of an absolute value can be improved if 2 wavelengths was used.We has also carried out preliminary examination of the assessment of peripheral circulatory function using photosensors. The apparatus, the principle involved in measurement, the assessment of elasticity and nonlinear characteristics of the digital arteries, the measurement of tissue blood volume was establishied.