A Caltech Library Service

Near-infrared spectroscopy of a heterogeneous turbid system containing distributed absorbers

Liu, Hanli and Hielscher, Andreas H. and Beauvoit, Bertrand and Wang, Lihong and Jacques, Steven L. and Tittel, Frank K. and Chance, Britton (1995) Near-infrared spectroscopy of a heterogeneous turbid system containing distributed absorbers. In: Photon Transport in Highly Scattering Tissue. Proceedings of SPIE. No.2326. Society of Photo-optical Instrumentation Engineers (SPIE) , Bellingham, WA, pp. 164-172. ISBN 9780819416599.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


In most biological tissues, absorbers such as blood in the blood vessels are localized within a low-absorbing background medium. To study the effect of distributed absorbers on the near infrared reflectance, we developed a Monte Carlo code and performed time-domain measurements on heterogeneous tissue-vessel models. The models were made of low absorbing polyester resin mixed with TiO_2 as scatters. A series of tubes with diameters of 3.2 or 6.4 mm were made in the resin sample. The volume ratio of the tubes to the total sample is about 20%. During the measurement, these tubes were filled with turbid fluids with different absorption coefficients to simulate blood in various oxygenation states. We found that the apparent absorption coefficient of the resin/tube system, determined by using the diffusion equation fit, can be approximated by a volume-weighted sum of the absorption coefficients of the different absorbing components. This approximation has to be replaced by a more complex expression if the difference in absorption between the absorbers and background is very large (approximately 20 times). The results of the tissue phantom study are supported by the Monte Carlo simulation. Possible explanations for the photon migration in this kind of heterogeneous system is also presented.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Wang, Lihong0000-0001-9783-4383
Additional Information:© 1995 Society of Photo-Optical Instrumentation Engineers (SPIE).
Series Name:Proceedings of SPIE
Issue or Number:2326
Record Number:CaltechAUTHORS:20181207-161549846
Persistent URL:
Official Citation:Hanli Liu, Andreas H. Hielscher, Bertrand Beauvoit, Lihong V. Wang, Steven L. Jacques, Frank K. Tittel, Britton Chance, "Near-infrared spectroscopy of a heterogeneous turbid system containing distributed absorbers," Proc. SPIE 2326, Photon Transport in Highly Scattering Tissue, (31 January 1995); doi: 10.1117/12.200817
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91625
Deposited By: George Porter
Deposited On:12 Dec 2018 00:18
Last Modified:16 Nov 2021 03:42

Repository Staff Only: item control page