Share Email Print

Journal of Biomedical Optics

Reducing motion artifacts in photoplethysmograms by using relative sensor motion: phantom study
Author(s): Ralph W. C. G. R. Wijshoff; Massimo Mischi; Jeroen Veen; Alexander M. Van Der Lee; Ronald M. Aarts
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

Currently, photoplethysmograms (PPGs) are mostly used to determine a patient's blood oxygenation and pulse rate. However, PPG morphology conveys more information about the patient's cardiovascular status. Extracting this information requires measuring clean PPG waveforms that are free of artifacts. PPGs are highly susceptible to motion, which can distort the PPG-derived data. Part of the motion artifacts are considered to result from sensor-tissue motion and sensor deformation. It is hypothesized that these motion artifacts correlate with movement of the sensor with respect to the skin. This hypothesis has been proven true in a laboratory setup. In vitro PPGs have been measured in a skin perfusion phantom that is illuminated by a laser diode. Optical motion artifacts are generated in the PPG by translating the laser diode with respect to the PPG photodiode. The optical motion artifacts have been reduced significantly in vitro, by using a normalized least-mean-square algorithm with only a single coefficient that uses the laser's displacement as a reference for the motion artifacts. Laser displacement has been measured accurately via self-mixing interferometry by a compact laser diode with a ball lens integrated into the package, which can be easily integrated into a commercial sensor.

Paper Details

Date Published: 29 November 2012
PDF: 15 pages
J. Biomed. Opt. 17(11) 117007 doi: 10.1117/1.JBO.17.11.117007
Published in: Journal of Biomedical Optics Volume 17, Issue 11
Show Author Affiliations
Ralph W. C. G. R. Wijshoff, Technische Univ. Eindhoven (Netherlands)
Massimo Mischi, Technische Univ. Eindhoven (Netherlands)
Jeroen Veen, Philips Research (Netherlands)
Alexander M. Van Der Lee, Philips Research (Netherlands)
Ronald M. Aarts, Technische Univ. Eindhoven (Netherlands)

© SPIE. Terms of Use
Back to Top