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Quantitation of Pathlength in Optical Spectroscopy

  • D. T. Delpy
  • S. R. Arridge
  • M. Cope
  • D. Edwards
  • E. O. R. Reynolds
  • C. E. Richardson
  • S. Wray
  • J. Wyatt
  • P. van der Zee
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 248)

Abstract

The relative transparency of tissues to near infrared light means that it is possible to transilluminate intact organs. In the infrared region, oxygen dependent absorptions due to haemoglobin and cytochrome aa3 can be observed, and it is therefore possible to monitor changes in both the blood and tissue oxygenation of the organ.1 This monitoring technique is particularly applicable to the study of the brain since there is no interfering absorption from myoglobin, and recent technical developments of the instrumentation have made it possible to transilluminate 8–9 cm of brain tissue.2 However, once measurements of absorption change at several wavelengths are available, there are still considerable problems in converting this data into quantitative changes in the concentration of oxy and deoxy haemoglobin and of oxidised cytochrome aa3.

Keywords

Monte Carlo Model Streak Camera Light Transport Scatter Phase Function Ultrashort Light Pulse 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Jobsis F.F. “Non invasive infrared monitoring of cerebral and myocardial oxygen sufficiency and circulatory parameters” Science, 198, 1264–1267 (1977).PubMedCrossRefGoogle Scholar
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    Cope, M., Delpy, D.T. “System for long term measurement of cerebral blood and tissue oxygenation on newborn infants by near infrared transillumination” Med. & Biol. Eng. & Comp. 222, 183–190, (1988).Google Scholar
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    Cope, M., Delpy, D.T., Reynolds, E.O.R., Wray, S., Wyatt, J.S., van der Zee, P. “Methods of quantitating cerebral near infrared spectroscopy data” Adv. Exp. Med & Biol. 222, 183–190, (1988).Google Scholar
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    Wray, S., Cope, M., Delpy, D.T., Wyatt, J.S., Reynolds, E.O.R. “Characterisation of the near infrared absorption spectra of cytochrome aa3 and haemoglobin for the non invasive monitoring of cerebral oxygenation” Biochim, Biophys. Acta. 933, 184–192, (1988).CrossRefGoogle Scholar
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    Delpy, D.T., Cope, M., van der Zee, P., Arridge, S., Wray S., Wyatt, J.S. “Estimation of optical path length through tissue from direct time of flight measurement” Phys. in Med. & Biol, (in press).Google Scholar
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    Svaasand, L.O., Ellinsen, R., “Optical properties of human brain” Photochem. & Photbiol. 38, 293–299, (1983).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • D. T. Delpy
    • 1
  • S. R. Arridge
    • 1
  • M. Cope
    • 1
  • D. Edwards
    • 2
  • E. O. R. Reynolds
    • 2
  • C. E. Richardson
    • 1
  • S. Wray
    • 3
  • J. Wyatt
    • 2
  • P. van der Zee
    • 1
  1. 1.Department of Medical PhysicsUniversity College LondonLondonUK
  2. 2.Department of Medical PaediatricsUniversity College LondonLondonUK
  3. 3.Department of Medical PhysiologyUniversity College LondonLondonUK

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