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Development of a real-time, semi-capacitive impedance phlebography device Cover

Development of a real-time, semi-capacitive impedance phlebography device

Journal of Electrical Bioimpedance
Volume 6 (2015): Issue 1 (January 2015)
By: Sören Weyer,  Hannes Weber,  Christian Kleeberg,  Steffen Leonhardt and  Tobias Wartzek  
Open Access
|Apr 2015

Figures & Tables

Fig. 1

System concept of the semi-capacitive impedance phlebography device.
System concept of the semi-capacitive impedance phlebography device.

Fig. 2

Measuring arrangement for impedance measurement with two or four electrodes and the corresponding equivalent electric circuit.
Measuring arrangement for impedance measurement with two or four electrodes and the corresponding equivalent electric circuit.

Fig. 3

Circuit diagram of the active electrode.
Circuit diagram of the active electrode.

Fig. 4

Upper and lower sides of the active electrode and the measuring arrangement. In the right picture the blue circles mark the positions of the outer current electrodes and the red circles mark the position of the measuring electrodes.
Upper and lower sides of the active electrode and the measuring arrangement. In the right picture the blue circles mark the positions of the outer current electrodes and the red circles mark the position of the measuring electrodes.

Fig. 5

Circuit diagram of the differential amplifier.
Circuit diagram of the differential amplifier.

Fig. 6

Filter for detection of maxima of sa(n).
Filter for detection of maxima of sa(n).

Fig. 7

Measured impedance signal sa(n) and the filtered signals sf(n) and sdf(n). The red cross in sf(n) mark the maxima which are detected by the algorithm.
Measured impedance signal sa(n) and the filtered signals sf(n) and sdf(n). The red cross in sf(n) mark the maxima which are detected by the algorithm.

Fig. 10

Measured signal sa(n) of a 1.8 kΩ resistance at fs = 64Hz, fs = 24 kHz and varying clock frequencies fCLK,AFE.
Measured signal sa(n) of a 1.8 kΩ resistance at fs = 64Hz, fs = 24 kHz and varying clock frequencies fCLK,AFE.

Fig. 9

Bland-Altman plot of the new measurement device and the PPG as gold standard of the bent leg.
Bland-Altman plot of the new measurement device and the PPG as gold standard of the bent leg.

Measurement period and number of detected pulse waves for the bent and stretched leg_

periodNPPGNIPGNTPNFNNFP
bent leg128 s1509797530
stretched leg100 s1168181350
DOI: https://doi.org/10.5617/jeb.953 | Journal eISSN: 1891-5469
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Language: English
Page range: 2 - 9
Submitted on: Oct 14, 2014
Published on: Apr 3, 2015
Published by: University of Oslo
In partnership with: Paradigm Publishing Services
Publication frequency: 1 issue per year
Keywords:
chronic venous insufficiency,
impedance plethysmography,
capacitive measurement,
real-time detection algorithm
Related subjects:
Engineering,
Bioengineering and biomedical engineering,
Biomedical electronics,
Life sciences,
Biophysics,
Medicine,
Biomedical engineering,
Physics,
Spectroscopy and metrology

© 2015 Sören Weyer, Hannes Weber, Christian Kleeberg, Steffen Leonhardt, Tobias Wartzek, published by University of Oslo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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