Dosimetric characterization of low energy brachytherapy sources: measurements

Low energy photon emitter brachytherapy sources are being used with increasing frequency for interstitial implants in tumor sites, especially the prostate. Recently, several new designs of ¹²⁵I and ¹⁰³Pd sources have become commercially available for clinical applications. Dosimetric characteristics (i.e. dose rate constant, radial dose function, and anisotropy function) of this source were experimentally and theoretically determined following the AAPM Task Group 43 (TG-43) recommendations and were related to the 1999 NIST calibration assigned to this source [S_k, 99std]. Measurements were performed in a Solid Water phantom using LiF thermoluminescent dosimeters and MD55-2 radiochromic films. The calculations were performed using Monte Carlo simulation techniques in Solid Water and liquid water. The goal of this presentation is to describe the experimental method of dosimetry of the brachytherapy sources