A comparison between transport and diffusion calculations using a finite element-spherical harmonics radiation transport method

ATALAY E. D., de Oliveira C., Goddard A.

MEDICAL PHYSICS, cilt.29, sa.9, ss.2013-2023, 2002 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 29 Sayı: 9
  • Basım Tarihi: 2002
  • Doi Numarası: 10.1118/1.1500404
  • Dergi Adı: MEDICAL PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.2013-2023
  • Anahtar Kelimeler: photon migration, Boltzmann transport equation, finite elements, spherical harmonics, anisotropic scattering, IMAGE-RECONSTRUCTION, LIGHT-PROPAGATION, PHOTON MIGRATION, NONSCATTERING REGIONS, HETEROGENEOUS TISSUES, BOUNDARY-CONDITIONS, OPTICAL TOMOGRAPHY, BIOLOGICAL TISSUES, NEUTRON-TRANSPORT, PHASE FUNCTION
  • Çanakkale Onsekiz Mart Üniversitesi Adresli: Evet

Özet

Most researchers choose the diffusion approximation to the transport equation as the model to describe photon migration in biological tissues. However, the applicability of this approximation is limited and, in certain cases, invalid. In this paper we introduce a two-dimensional, finite element-spherical harmonics (FE-P-N) radiation transport method for the simulation of light propagation in tissue. The propagation of light is investigated first in a layered cylinder, which can be seen as a very simplistic approximation of a human head. Effects of the anisotropy factor g on the photon migration is then examined in homogeneous and heterogeneous media for different values of g and mu(s). The influence of void-like heterogeneities and channels in which absorption and scattering are very small compared with the surrounding medium on the transport of photons is also investigated. Significant differences between transport and diffusion calculations are shown to occur in all cases. (C) 2002 American Association of Physicists in Medicine.