Choice of phantom material for the dosimetry of /sup 192/Ir sources

Journal Article · Tue Mar 01 04:00:00 EST 1988 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(88)90280-5· OSTI ID:5156702

Meli, J A; Meigooni, A S; Nath, R

Dosimetric characteristics of polystyrene, solid water, and polymethylmethacrylate were examined and compared to water to determine the suitability of these solid materials for the dosimetry of /sup 192/Ir. Ionization charge measured in each of the four media as a function of depth and depth-dose curves calculated by Monte Carlo simulation show that the three solids are equivalent to each other and to water under full scattering conditions. Photon energy spectra generated from the Monte Carlo simulation show little variation for the different media. Mass energy absorption coefficients and exposure-to-dose conversion factors were calculated as a function of depth for these spectra. Measured tissue attenuation factors are in excellent agreement with Meisberger's selected values. The radial dose function, which describes the change in dose with distance in phantom exclusive of the inverse square law, was calculated from the tissue attenuation factor and found to be in significant disagreement with Dale's Monte Carlo values. The reason for this discrepancy is discussed.

• Research Organization: Yale Univ. School of Medicine, New Haven, CT (USA)
• OSTI ID: 5156702
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Journal Name: Int. J. Radiat. Oncol., Biol. Phys.; (United States) Vol. 14:3; ISSN IOBPD
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
655003* -- Medical Physics-- Dosimetry
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CARBOXYLIC ACID ESTERS
COMPARATIVE EVALUATIONS
DAYS LIVING RADIOISOTOPES
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INTERNAL CONVERSION RADIOISOTOPES
IRIDIUM 192
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ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MATERIALS
METHACRYLIC ACID ESTERS
METHYL METHACRYLATE
MINUTES LIVING RADIOISOTOPES
MONTE CARLO METHOD
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
RADIATION DOSE DISTRIBUTIONS
RADIOISOTOPES
SPATIAL DOSE DISTRIBUTIONS
TISSUE-EQUIVALENT MATERIALS
WATER
YEARS LIVING RADIOISOTOPES