title: Photon absorbed fractions for cylindrical geometry: homogeneous nonradioactive cylinder containing a homogeneous cylindrical distribution of activity.
abstract: The purpose of this study was to calculate photon absorbed fractions in tissue surrounding a radioactive source where both the source and the surrounding tissue are assumed to have cylindrical geometry. Specifically, we treated two cases: the case of a cylindrical source of homogeneous activity placed in air, and second, the case of a cylindrical source of homogeneous activity placed in a cylindrical nonradioactive absorbing material. In this study we offer an analytical solution to these problems followed by numerical integration. The computer program allowed for very general calculations, e.g., different tissues, different geometrical setups. Tables of absorbed fractions have been developed for commonly used radionuclide energies and tissue-equivalent material. A comparison between our results and the results of other related studies showed the advantages and limitations of this approach.
authors.affiliation: Department of Physics and Astronomy, University of Wyoming, Laramie, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Dreesen
authors.forename: D I
authors.initials: DI
authors.lastname: Dumitru
authors.forename: T C
authors.initials: TC
authors.lastname: Fearon
authors.forename: D C
authors.initials: DC
authors.lastname: Kushner
mesh_terms: D001918:Brachytherapy; D006801:Humans; D008433:Mathematics; D008961:Models, Structural; D019047:Phantoms, Imaging; D017785:Photons