Skip to main content
Log in

In vitro comparison of different signal processing algorithms used in laser Doppler flowmetry

  • Physiological Measurement
  • Published:
Medical and Biological Engineering and Computing Aims and scope Submit manuscript

Abstract

The paper reports the results of investigations comparing the relative in vitro responses of different signal processing algorithms commonly employed in laser Doppler flowmetry (LDF). A versatile laser Doppler system is described which enabled complex signal processing to be implemented relatively simply using digital analysis. The flexibility of the system allowed a variety of processing algorithms to be studied by simply characterising the algorithm of interest under software control using a personal computer. An in vitro physical model is also presented which was used to maintain reproducible fluid flows. Flows of particles were studied in a physical model using both a near-infra-red (NIR) diode and an He/Ne laser source. The results show that frequency-weighted algorithms are responsive to both particle velocity and concentration, whereas non-weighted algorithms respond to concentration only. The linearity of the velocity response is critically dependent on both the dimensions of the in vitro model and the frequency bandwidth of the signalprocessing algorithm.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Berne, B. J. andPecora, R. (1976)Dynamic light scattering. John Wiley & Sons Inc., New York.

    Google Scholar 

  • Boggett, D., Obeid, A. N., Blond, J. andRolfe, P. (1986) Calibration of a laser Doppler skin blood flow meter using a simple fluid model and digital signal processing. InElectronics in medicine and biology—selected papers.Copeland, K. (Ed.), IERE, London, 241–247.

    Google Scholar 

  • Bonner, R. F., Bowen, P., Bowman, R. L. andNossal, R. (1978) Proc. Electro-Optics/Laser '78 Conf., Industrial & Scientific Conference Management Inc., Chicago,III, 539.

    Google Scholar 

  • Bonner, R. andNossal, R. (1981) Model for laser Doppler measurements of blood flow in tissue.Appl. Optics.,20, 2097–2107.

    Article  Google Scholar 

  • Holloway, G. A. andWatkins, D. W. (1977) Laser Doppler measurement of cutaneous blood flow.J. Invest. Dermatol.,69, 306–309.

    Article  Google Scholar 

  • Holloway, G. A. (1980) Cutaneous blood flow responses to injection trauma measured by laser Doppler velocimetry. ——Ibid.,74, 1–4.

    Article  Google Scholar 

  • Nilsson, G. E., Tenland, T. andÖberg, P. Å. (1980a) Evaluation of a laser Doppler flowmeter for measurement of tissue blood flow.IEEE Trans.,BME-27, 597–604.

    Google Scholar 

  • Nilsson, G. E., Tenland, T. andÖberg, P. Å. (1980b) A new instrument for continuous measurement of tissue blood flow by light beating spectroscopy. ——Ibid.,BME-27, 12–19.

    Google Scholar 

  • Nilsson, G. E. (1984) Signal processor for laser Doppler tissue flowmeters.Med. & Biol. Eng. & Comput.,22, 343–348.

    Article  Google Scholar 

  • Obeid, A. N., Boggett, D., Barnett, N. J., Dougherty, G. andRolfe, P. (1988) Depth discrimination in laser Doppler skin blood flow measurement using different lasers. ——Ibid.,26, 415–419.

    Article  Google Scholar 

  • Obeid, A. N. (1989) The measurement of blood flow in the microcirculation using laser Doppler flowmetry. Ph.D. Thesis, CNAA, Oxford Polytechnic.

  • Obeid, A. N., Barnett, N. J., Dougherty, G. andWard, G. (1990a) A critical review of laser Doppler flowmetry.J. Med. Eng. & Technol.,14, 178–181.

    Google Scholar 

  • Obeid, A. N., Dougherty, G. andPettinger, S. (1990b)In vivo comparison of a twin wavelength laser Doppler flowmeter using He−Ne and laser diode sources. ——Ibid.,,14, 102–110.

    Google Scholar 

  • Öberg, P. Å., Tenland, T. andNilsson, G. E. (1983) Laser Doppler flowmetry—a noninvasive and continuous method for blood flow evaluation in microvascular studies.Acta Med. Scand., Suppl. 687, 17–24.

    Google Scholar 

  • Stern, M. D., Lappe, D. L., Bowen, P. D., Chimosky, J. E., Holloway, G. A., Keiser, H. R. andBowman, R. L. (1977) Continuous measurement of tissue blood flow by laser Doppler spectroscopy.Am. J. Physiol.,232, H441-H448.

    Google Scholar 

  • Watkins, D. andHolloway, G. A. (1978) An instrument to measure cutaneous blood flow using the Doppler shift of laser light.IEEE Trans.,BME-25, 28–33.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Obeid, A.N. In vitro comparison of different signal processing algorithms used in laser Doppler flowmetry. Med. Biol. Eng. Comput. 31, 43–52 (1993). https://doi.org/10.1007/BF02446892

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02446892

Keywords

Navigation