Light transport in biological tissue based on the simplified spherical harmonics equations

Journal Article · Wed Dec 20 04:00:00 EST 2006 · Journal of Computational Physics

DOI:https://doi.org/10.1016/j.jcp.2006.07.007· OSTI ID:20840371

Klose, Alexander D ^[1]; Larsen, Edward W ^[2]

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1. Department of Radiology, Columbia University, New York, NY 10032 (United States)
2. Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)

In this work, we demonstrate the validity of the simplified spherical harmonics equations to approximate the more complicated equation of radiative transfer for modeling light propagation in biological tissue. We derive the simplified spherical harmonics equations up to order N = 7 for anisotropic scattering and partially reflective boundary conditions. We compare numerical results with diffusion and discrete ordinates transport solutions. We find that the simplified spherical harmonics methods significantly improve the diffusion solution in transport-like domains with high absorption and small geometries, and are computationally less expensive than the discrete ordinates transport method. For example, the simplified P {sub 3} method is approximately two orders of magnitude faster than the discrete ordinates transport method, but only 2.5 times computationally more demanding than the diffusion method. We conclude that the simplified spherical harmonics methods can accurately model light propagation in small tissue geometries at visible and near-infrared wavelengths, yielding transport-like solutions with only a fraction of the computational cost of the transport calculation.

• OSTI ID: 20840371
• Journal Information: Journal of Computational Physics, Journal Name: Journal of Computational Physics Journal Issue: 1 Vol. 220; ISSN JCTPAH; ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ANISOTROPY
BOUNDARY CONDITIONS
DIFFUSION
DIFFUSION EQUATIONS
DISCRETE ORDINATE METHOD
GEOMETRY
LIGHT TRANSMISSION
MATHEMATICAL SOLUTIONS
OPTICS
RADIANT HEAT TRANSFER
SCATTERING
SIMULATION
SPHERICAL HARMONICS
SPHERICAL HARMONICS METHOD
TRANSPORT THEORY
VISIBLE RADIATION
WAVELENGTHS