Preliminary Study Of Applying High Sensitive Near Infrared Spectroscopy To Evaluate The Function State Of Vessels

Near infrared spectroscopy (NIRS) is a promising technique, which had developed rapidly in past decades for it can provide continuous, noninvasive information on blood oxygenation in vivo. It contains two leading areas, pulse oximetry and cerebral spectroscopy. Pulse oximetry and some kinds of cerebral spectroscopy have been manufactured and widely used in clinic.In the current models of blood oxygenation detection, pulse oximetry explores pulse signals only, while cerebral spectroscopy's algorithms involve trend signals only. They interpret changes of light signals as changes of blood oxygen saturation, but overlook changes of light signals due to changes of blood volume in arteries and veins. Devices based on these models are implemented by partition different frequency components of light signal by filters. If used for new purposes, this type of devices will bring large system error, and the results would be doubtful.Base on the model of tissue light absorption, this dissertation...