Optical sensor system for peripheral vascular diagnostics of the patients based on pulse spectroscopy method

Non-invasive continuous real-time assessment of patient conditions for the diagnostic purposes is a target of the state-of-the-art clinical monitoring technology. Such a surveillance system for the peripheral vascular diagnostics was designed during current research by combining the pulse spectroscopy and advanced signal processing. Analysis of the rhythmic activities in blood circulation reveals a state of the cardiovascular control mechanisms. Considering that the photo-plethysmographic (PPG) waveform is a pressure-induced signal, the correlation between the pulse features with pressure-resistance characteristics of the vessels was derived. By means of the pulse-contour-analysis (PCA) specific amplitudes, systolic slope, dicrotic transit time etc. can be extracted. It was found that the power spectra of the wavelet spectrograms expose significant diagnostic information about the cardiovascular control mechanisms of the microcirculation.