LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY.

Massoud Motamedi, W. F. Cheong, G. Yoong, A. J. Welch

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Recent measurements of the phase function of biological tissue such as blood and skin for visible and near-IR wavelengths indicate a highly anisotropic scattering behavior. This suggests that the photon diffusion approximation is not valid for thin layers of an anistropic medium or in the near-surface regions of optically thick tissues. Instead, a combination of small-angle scattering approximation to account for the anisotropic component of the phase function and the diffusion approximation has been used to study the off-axis propagation in biological tissues with a high degree of anisotropy. The former computes the near-axis radiance, and the latter estimates the off-axis light spatial distribution using the on-axis radiance as an external source. The results of the computation of total light intensity as a function of axial as well as radial distance for a 2-mm spot size show the existence of two regions. In the first region, proximal to the surface, scattering is confined to a narrow forward angle. This is followed by a second region of more diffuse scattering. These results indicate that for highly anisotropic scattering the combined model gives a better estimation of the spatial light distribution than each model independently.

Original languageEnglish (US)
Title of host publicationUnknown Host Publication Title
Place of PublicationWashington, DC, USA
PublisherOptical Soc of America
Pages98-100
Number of pages3
ISBN (Print)0936659491
StatePublished - 1987
Externally publishedYes

Fingerprint

Laser beams
Anisotropy
Scattering
Tissue
Surface scattering
Spatial distribution
Skin
Blood
Photons
Wavelength

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Motamedi, M., Cheong, W. F., Yoong, G., & Welch, A. J. (1987). LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY. In Unknown Host Publication Title (pp. 98-100). Washington, DC, USA: Optical Soc of America.

LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY. / Motamedi, Massoud; Cheong, W. F.; Yoong, G.; Welch, A. J.

Unknown Host Publication Title. Washington, DC, USA : Optical Soc of America, 1987. p. 98-100.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Motamedi, M, Cheong, WF, Yoong, G & Welch, AJ 1987, LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY. in Unknown Host Publication Title. Optical Soc of America, Washington, DC, USA, pp. 98-100.
Motamedi M, Cheong WF, Yoong G, Welch AJ. LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY. In Unknown Host Publication Title. Washington, DC, USA: Optical Soc of America. 1987. p. 98-100
Motamedi, Massoud ; Cheong, W. F. ; Yoong, G. ; Welch, A. J. / LASER BEAM PROPAGATION IN BIOLOGICAL TISSUE WITH STRONG ANISOTROPY. Unknown Host Publication Title. Washington, DC, USA : Optical Soc of America, 1987. pp. 98-100
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