Modeling rhenium-186 and rhenium-188 distribution in a neutron-activated rhenium wire and effect of the distribution on beta dosimetry in a water phantom

Radioactive beta-emitting rhenium wire brachytherapy sources produced by ne utron activation in an isotropic thermal neutron field have a non-uniform r adial radioisotope distribution. We modeled this distribution and confirmed the model by experimental measurements on wires of 0.1-1.0 mm diameter. Wh en the corrected radial distributions of Re-186 and Re-188 were used, the c alculated dose distribution around a 0.5-mm wire agreed with the distributi on measured with Gafchromic film in a solid water phantom to within 5.0% ov er the therapeutic range (radius of 0.4-2.8 mm). (C) 1999 Elsevier Science Ltd. All rights reserved.