Abstract
Laser Doppler Flowmetry, LDF has been widely utilized in bio-industry. In general, blood flow measuring are categorized into invasive and non-invasive methods. Invasive measurement enjoys the benefits of accuracy, however, it is criticized for causing discomfort, injury or infection and requires more professional medical assistance. On the other hand, LDF is non-invasive, lightweight, easy to operate and without any fluids contact. In addition, LDF can be used to diagnose diseases more effectively with information obtained from tissue microcirculation. It is obvious LDF technology has played a significant role in clinical microcirculation as well as biomedical engineering. The aim of this study is to create a system utilized to monitor and analyze human microcirculation blood flow. Therefore, stability is a key feature of this design. Two major experiments were conducted in this research: in-vitro and in-vivo measurement. Human microcirculation varies due to different temperatures, breathing, emotions and pulses. At first, we use milk powder as trial liquids to identify SNR, linearity and stability in different flow rates and concentrations. In the next stage, horse blood is used for the same experiment. Compared with an average of 5% stability in commercial applications, our system is more stable cited at 1% or less and has better linearity of 5%. Finally, we use the system to measure human microcirculation blood flow by observing the change of blood pressure. The device allows us to monitor the immediate change of blood flows and the data analyses with the aids of LabVIEW. To sum up, we have successfully set up a non-invasive system that can be used to monitor the change of microcirculation blood flows in more stable and effective way with less cost compared with commercial devices.