Development of new two-dosimeter algorithm for effective dose in ICRP Publication 103.

The two-dosimeter method, which employs one dosimeter on the chest and the other on the back, determines the effective dose with sufficient accuracy for complex or unknown irradiation geometries. The two-dosimeter method, with a suitable algorithm, neither significantly overestimates (in most cases) nor seriously underestimates the effective dose, not even for extreme exposure geometries. Recently, however, the definition of the effective dose itself was changed in ICRP Publication 103; that is, the organ and tissue configuration employed in calculations of effective dose, along with the related tissue weighting factors, was significantly modified.

Dosimetric characterization of 142Pr glass seeds for brachytherapy.

A glass bead consisted of the beta(-)-emitting (142)Pr is proposed for brachytherapy treatment of prostate cancer. Appropriate radionuclide and seed dimensions were selected and sample seeds were manufactured. For the quantitative dosimetric parameters, two-dimensional dose distributions were calculated using the MCNP5 Monte Carlo code and measured using radiochromic film.

Dose calculation of 142Pr microspheres as a potential treatment for arteriovenous malformations.

Arteriovenous malformation (AVM), especially cryptic AVM, can cause highly variable cerebral neurological defects. Injection of 142Pr microspheres into arteries feeding an AVM in order to simulate radio-embolism has been proposed as a novel treatment method. To investigate optimization of radiation dose to the clinically important arterial wall area, preliminary dosimetric studies have been performed.

Dose backscatter factors for selected beta sources as a function of source, calcified plaque and contrast agent using Monte Carlo calculations.

Electron backscattering is a prominent secondary effect in beta dosimetry, and is closely correlated with factors such as the geometries of the source and the scattering material, as well as the composition of the scattering material. Previous results were varied depending on the experimental setup and detector resolution, and were generally performed for monoenergetic electron beams, which makes direct application of these factors to beta sources difficult. In this work, backscattering factors were calculated with MCNP 4C for selected beta sources currently in use (32P and 90Sr/90Y) as well as for sources of potential therapeutic use (45Ca, 142Pr and 185W).