Measurement of the absorbed dose distribution near an Ir-192 intravascular brachytherapy seed using a high-spatial-resolution gel dosimetry system
Por:
Massillon-JL, G, Minniti, R, Mitch, MG, Soares, CG
Publicada:
7 jun 2012
Resumen:
The absorbed dose distribution at sub-millimeter distances from the Best single Ir-192 intravascular brachytherapy seed was measured using a high-spatial-resolution gel dosimetry system. Two gel phantoms from the same batch were used; one for the seed irradiation and one for calibration. Since the response of this gel is energy independent for photons between 20 and 1250 keV, the gel was calibrated using a narrowly collimated Co-60 gamma-ray beam (cross-sectional area similar to 1 cm(2)). A small format laser computed tomography scanner was used to acquire the data. The measurements were carried out with a spatial resolution of 100 mu m in all dimensions. The seed was calibrated at NIST in terms of air-kerma strength. The absorbed dose rate as well as the radial dose function, g(L)(r), was measured for radial distances between 0.6 and 12.6 mm from the seed center. The dose rate constant was measured, yielding a value of Lambda = (1.122 +/- 0.032) cGy h(-1) U-1, which agrees with publis
Filiaciones:
Massillon-JL, G:
Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico
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