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A Time Resolved Spectroscopic (TRS) Study of Migration of Visual to Infrared Waves in Brain Tissue in Relation to Absorption of Hemoproteins

  • S. Nioka
  • G. Holtom
  • H. Miyake
  • M. Maris
  • B. Chance
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 277)

Abstract

Previous optical spectroscopic studies of brain tissue revealed that only short photon migration distributions yeilds absorption spectra in the visual wavelength range (Heinrich et al. 1985), while longer wavelengths penetrated over greater distances (Brazy et al., 1985). The alpha and beta bands of hemoproteins in brain tissue have extremely high absorption coefficients which reduce the length of light migration distributions. This phenomena can be explained by photon migration theory. As shown in Figure 1A, in scattering media such as a brain tissue, light path lengths have a distribution function. In this figure, the Y-axis represents the log of photon intensity (I) or number of photons, and the X-axis represents time in nanoseconds. Migrating light path lengths (L), can be represented by use of the conversion factor: 1 ns = 23 cm (light path length in water).

Keywords

Hemoglobin Concentration Brain Homogenate Perfuse Brain Visual Wavelength Range Time Resolve Spectroscopy 
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. Brazy, J. E., Lewis, D. V., Mitnick, M. H., and Jöbsis, F. F., 1989, Noninvasive monitoring of cerebral oxygenation in preterm infants: preliminary observations. Pediatrics. 75:217–225.Google Scholar
  2. Heinrich, U., Hoffmann, J., Baumgärtl, H., Yu, B., Lübbers, D. W., 1985. Oxygen supply of the blood-free perfused buinea pig brain at three different temperatures. Adv. Exp. Med. Biol., 191:77–90.PubMedCrossRefGoogle Scholar
  3. Patterson, M. S., Chance, B., and Wilson, B. C., 1989, Time resolved reflectance and transmittance for the non-invasive measurement of tissue optical properties, Applied Optics. 28:2331–2336.PubMedCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • S. Nioka
    • 1
  • G. Holtom
    • 1
  • H. Miyake
    • 1
  • M. Maris
    • 1
  • B. Chance
    • 1
  1. 1.Department of Biochemistry/Biophysics and Department of ChemistryUniversity of PennsylvaniaPhiladelphiaUSA

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