Brachytherapy dosimetry parameters calculated for a 131Cs source.
A comprehensive analysis of the IsoRay Medical model CS-1 Rev2 131Cs brachytherapy source was performed. Dose distributions were simulated using Monte Carlo methods (MCNP5) in liquid water, Solid Water, and Virtual Water spherical phantoms. From these results, the in-water brachytherapy dosimetry parameters have been determined, and were compared with those of Murphy et al. [Med. Phys. 31, 1529-1538 (2004)] using measurements and simulations. Our results suggest that calculations obtained using erroneous cross-section libraries should be discarded as recommended by the 2004 AAPM TG-43U1 report. Our Mclambda value of 1.046+/-0.019 cGy h(-1) U(-1) is within 1.3% of that measured by Chen et al. [Med. Phys. 32, 3279-3285 (2005)] using TLDs and the calculated results of Wittman and Fisher [Med. Phys. 34, 49-54 (2007)] using MCNP5. Using the discretized energy approach of Rivard [Appl. Radiat. Isot. 55, 775-782 (2001)] to ascertain the impact of individual 131Cs photons on radial dose function and anisotropy functions, there was virtual equivalence of results for 29.461< or =Egamma< or = 34.419 keV and for a mono-energetic 30.384 keV photon source. Comparisons of radial dose function and 2D anisotropy function data are also included, and an analysis of material composition and cross-section libraries was performed.
Rivard
Mark J
MJ
Department of Radiation Oncology, Tufts-New England Medical Center Tufts University School of Medicine, Box #246, 750 Washington Street, Boston, Massachusetts 02111, USA.
D001918:Brachytherapy / Q000295:instrumentation*; D002588:Cesium Radioisotopes / Q000032:analysis* / Q000627:therapeutic use*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D019736:Prostheses and Implants; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*
D002588:Cesium Radioisotopes