Light and temperature distribution in laser irradiated tissue

The influence of anisotropic scattering and refractive index

Massoud Motamedi, Sohi Rastegar, Gerald Lecarpentier, Ashley J. Welch

Research output: Contribution to journalArticle

72 Citations (Scopus)

Abstract

The rigorous method of discrete ordinates was used to evaluate the effects of anisotropic scattering and optical discontinuity at the boundaries on light and temperature distribution in tissue. The influence of optical parameters of tissue on its thermal response was examined by using a finite element solution of the heat conduction equation. Calculations were performed for wide ranges of scattering albedo, the anisotropy factor, as well as interface reflectivities. This study shows that the presence of an optical discontinuity due to an air-tissue interface forces the maximum peak intensity to move from subsurface to the surface for tissue with high scattering albedo, which leads to a higher fluence rate in the near surface region. Temperature field calculations show a higher subsurface temperature for a highly scattering medium during tissue coagulation. Neglecting the anisotropic properties of tissue as well as the optical discontinuity at the boundaries would result in considerable error in the calculated temperature rises. Additionally the accuracy of the photon diffusion theory for predicting light and temperature distribution near the tissue surface is examined.

Original languageEnglish (US)
Pages (from-to)2230-2237
Number of pages8
JournalApplied Optics
Volume28
Issue number12
DOIs
StatePublished - Jun 15 1989
Externally publishedYes

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Refractive index
Temperature distribution
temperature distribution
Scattering
Tissue
refractivity
Lasers
scattering
lasers
discontinuity
albedo
diffusion theory
coagulation
Coagulation
Heat conduction
conductive heat transfer
fluence
Anisotropy
Photons
reflectance

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

Light and temperature distribution in laser irradiated tissue : The influence of anisotropic scattering and refractive index. / Motamedi, Massoud; Rastegar, Sohi; Lecarpentier, Gerald; Welch, Ashley J.

In: Applied Optics, Vol. 28, No. 12, 15.06.1989, p. 2230-2237.

Research output: Contribution to journalArticle

Motamedi, Massoud ; Rastegar, Sohi ; Lecarpentier, Gerald ; Welch, Ashley J. / Light and temperature distribution in laser irradiated tissue : The influence of anisotropic scattering and refractive index. In: Applied Optics. 1989 ; Vol. 28, No. 12. pp. 2230-2237.
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