Premium
A photon spectrometric dose‐rate constant determination for the Advantage™ Pd‐103 brachytherapy source
Author(s) -
Chen Zhe Jay,
Bongiorni Paul,
Nath Ravinder
Publication year - 2010
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.3298011
Subject(s) - monte carlo method , dosimetry , photon , thermoluminescent dosimeter , brachytherapy , photon energy , physics , nuclear medicine , computational physics , medical physics , optics , statistics , mathematics , medicine , radiation therapy , radiology , dosimeter
Purpose: Although several dosimetric characterizations using Monte Carlo simulation and thermoluminescent dosimetry (TLD) have been reported for the new Advantage™ Pd‐103 source (IsoAid, LLC, Port Richey, FL), no AAPM consensus value has been established for the dosimetric parameters of the source. The aim of this work was to perform an additional dose‐rate constant ( Λ )determination using a recently established photon spectrometry technique (PST) that is independent of the published TLD and Monte Carlo techniques. Methods: Three Model IAPD‐103A Advantage™ Pd‐103 sources were used in this study. The relative photon energy spectrum emitted by each source along the transverse axis was measured using a high‐resolution germanium spectrometer designed for low‐energy photons. For each source, the dose‐rate constant was determined from its emitted energy spectrum. The PST‐determined dose‐rate constant ( ΛPST)was then compared to those determined by TLD( ΛTLD)and Monte Carlo( ΛMC)techniques. A likely consensus Λ value was estimated as the arithmetic mean of the average Λ values determined by each of three different techniques. Results: The average ΛPSTvalue for the three Advantage™ sources was found to be( 0.676 ± 0.026 )cGyh − 1U − 1. Intersource variation inΛPSTwas less than 0.01%. TheΛPSTwas within 2% of the reportedΛMCvalues determined by PTRAN , EGSnrc, and MCNP5 codes. It was 3.4% lower than the reportedΛTLD. A likely consensus Λ value was estimated to be( 0.688 ± 0.026 )cGyh − 1U − 1, similar to the AAPM consensus values recommended currently for the Theragenics (Buford, GA) Model 200( 0.686 ± 0.033 )cGyh − 1U − 1, the NASI (Chatsworth, CA) Model MED3633( 0.688 ± 0.033 )cGyh − 1U − 1, and the Best Medical (Springfield, VA) Model 2335( 0.685 ± 0.033 )cGyh − 1U − 1P103 d sources. Conclusions: An independent Λ determination has been performed for the Advantage™ Pd‐103 source. TheΛPSTobtained in this work provides additional information needed for establishing a more accurate consensus Λ value for the Advantage™ Pd‐103 source.