| Abstract [eng] |
As the population ages, vascular condition monitoring and care are becoming increasingly important. The aim of the thesis is to confirm or deny the hypothesis that the bio-impedance plethysmography signal is suitable for the localized assessment of the vascular condition and the detection of vascular occlusion zones. A study conducted, gathering data from 26 individuals of two different age groups showed, that limb blood flow measurements using bioimpedance plethysmography have very good quality. In the cases where no signal was obtained in parallel with photoplethysmography, the plethysmography signal of the impedance still provided morphological information for proper analysis. A method for detecting point c and d of the second-order derivative was proposed and statistically evaluated. It facilitates the detection of mentioned indexes in poor quality signals. After the conversion of the collected data into the parameters and their statistical evaluation, the parameters characterizing the eccentric elasticity and vascular aging were used to form a classifier for differentiating signals with and without abnormalities. It was evaluated by comparing its classification results with the results of the manual classification of 3 evaluators. The accuracy of the 82% classification was determined with 78% sensitivity and 85% specificity. After evaluating the dependence of reflections on simulated disorders, methods of detecting the changes that caused reflections were suggested. |
