Brachytherapy source characterization for improved dose calculations using primary and scatter dose separation

Russell, Kellie R.; Tedgren, Åsa Carlsson; Ahnesjö, Anders

doi:10.1118/1.1949767

Cited by 45 publications

(46 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…15,16 In addition to the TG-43 dosimetry parameters, dose-rate contributions are presented separately for primary, single-scattered, and multiple-scattered photons for high-energy sources. This method follows the formalism by Russell et al 18 that could be used in convolution/superposition methods 19 to calculate dose distributions around brachytherapy sources in heterogeneous media and under bounded conditions.…”

Section: D Carleton Laboratory For Radiotherapy Physicsmentioning

confidence: 99%

Supplement 2 for the 2004 update of theAAPMTask Group No. 43 Report: Joint recommendations by theAAPMandGEC‐ESTRO

et al. 2017

View full text Add to dashboard Cite

Cs (IsoRay Medical model CS-1 Rev2). Observations are included on the behavior of these dosimetry parameters as a function of radionuclide. Recommendations are presented on the selection of dosimetry parameters, such as from societal reports issuing consensus datasets (e.g., TG-43U1, AAPM Report #229), the joint AAPM/IROC Houston Registry, the GEC-ESTRO website, the Carleton University website, and those included in software releases from vendors of treatment planning systems. Aspects such as timeliness, maintenance, and rigor of these resources are discussed.Links to reference data are provided for radionuclides (radiation spectra and half-lives) and dose scoring materials (compositions and mass densities). The recent literature is examined on photon energy response corrections for thermoluminescent dosimetry of low-energy photon-emitting brachytherapy sources. Depending upon the dosimetry parameters currently used by individual physicists, use of these recommended consensus datasets may result in changes to patient dose calculations. These changes must be carefully evaluated and reviewed with the radiation oncologist prior to their implementation.

show abstract

Section: D Carleton Laboratory For Radiotherapy Physicsmentioning

confidence: 99%

Supplement 2 for the 2004 update of theAAPMTask Group No. 43 Report: Joint recommendations by theAAPMandGEC‐ESTRO

et al. 2017

View full text Add to dashboard Cite

show abstract

“…20-22͒ or larger. 23 Current trends support the use of large phantoms, providing full scatter within a radius of 20 cm from the source. 11 A recent comprehensive MC study 15 presenting single-source data on all available 192 Ir HDR and PDR sources used a cubic water phantom of dimensions 80 ϫ 80ϫ 80 cm 3 .…”

Section: Ir Dosimetrymentioning

confidence: 99%

Influence of phantom material and dimensions on experimental dosimetry

Tedgren

Carlsson

2009

Medical Physics

View full text Add to dashboard Cite

In treatment planning of brachytherapy, absorbed dose is calculated by superposing predetermined distributions of absorbed dose to water in water for the single source according to the irradiation pattern ͓i.e., placement of the source͑s͒ or dwelling position͑s͔͒. Single-source reference water data are derived from Monte Carlo ͑MC͒ simulations and/or experiments. For reasons of positional accuracy, experimental brachytherapy dosimetry is most often performed in plastic phantoms. This work investigates the water equivalence of phantoms made from polystyrene, PMMA, and solid water for 192 Ir dosimetry. The EGSnrc MC code is used to simulate radial absorbed dose distributions in cylindrical phantoms of dimensions ranging in size from diameter and height of 20 cm to diameter and height of 40 cm. Water equivalence prevails if the absorbed dose to water in the plastic phantom is the same as the absorbed dose to water in a water phantom at equal distances from the source. It is shown that water equivalence at a specified distance from the source depends not only on the size of the plastic phantom but also on the size of the water phantom used for comparison. Compared to equally sized water phantoms, phantoms of polystyrene are less water equivalent than phantoms of PMMA and solid water but compared to larger water phantoms they are the most water equivalent. Although phantom dimension is the most important single factor influencing the dose distributions around 192 Ir sources, the effect of material properties is nonnegligible and becomes increasingly important as phantom dimensions increase. The importance of knowing the size of the water phantom whose data underlies treatment planning systems, when using such data as a reference in, e.g., detector evaluation studies, is discussed. To achieve the highest possible accuracy in experimental dosimetry, phantom-specific correction factors should be used.

show abstract

“…The primary and scatter dose separation ͑PSS͒ formalism published by Russell et al 32 can be used in convolution/ superposition methods 33 to calculate dose distributions around brachytherapy sources in heterogeneous media. This PSS formalism has been recently used to characterize dosimetric properties of HDR 192 Ir and 169 Yb sources.…”

Section: Iie Calculations Of Primary and Scatter Dose Separationmentioning

confidence: 99%

TG‐43 U1 based dosimetric characterization of model 67‐6520 Cs‐137 brachytherapy source

Meigooni¹,

Wright²,

Koona³

et al. 2009

Medical Physics

View full text Add to dashboard Cite

Purpose: Brachytherapy treatment has been a cornerstone for management of various cancer sites, particularly for the treatment of gynecological malignancies. In low dose rate brachytherapy treatments, Cs source are measured using LiF thermoluminescent dosimeters in a Solid Water™ phantom material and calculated using Monte Carlo simulations with the GEANT4 code in Solid Water™ and liquid water. The dose rate constant, radial dose function, and two-dimensional anisotropy function of this source model were obtained following the TG-43 U1 recommendations. In addition, the primary and scatter dose separation ͑PSS͒ formalism that could be used in convolution/superposition methods to calculate dose distributions around brachytherapy sources in heterogeneous media was studied. Results: The measured and calculated dose rate constants of the IPL 137 Cs source in Solid Water™ were found to be 0.930͑Ϯ7.3%͒ and 0.928͑Ϯ2.6%͒ cGy h −1 U −1 , respectively. The agreement between these two methods was within our experimental uncertainties. The Monte Carlo calculated value in liquid water of the dose rate constant was ⌳ = 0.948͑Ϯ2.6%͒ cGy h −1 U −1 . Similarly, the agreement between measured and calculated radial dose functions and the anisotropy functions was found to be within Ϯ5%. In addition, the tabulated data that are required to characterize the source using the PSS formalism were derived. Conclusions: In this article the complete dosimetry of the newly designed 137 Cs IPL source following the AAPM TG-43 U1 dosimetric protocol and the PSS formalism is provided.

show abstract

Brachytherapy source characterization for improved dose calculations using primary and scatter dose separation

Cited by 45 publications

References 52 publications

Supplement 2 for the 2004 update of theAAPMTask Group No. 43 Report: Joint recommendations by theAAPMandGEC‐ESTRO

Supplement 2 for the 2004 update of theAAPMTask Group No. 43 Report: Joint recommendations by theAAPMandGEC‐ESTRO

Influence of phantom material and dimensions on experimental dosimetry

TG‐43 U1 based dosimetric characterization of model 67‐6520 Cs‐137 brachytherapy source

Contact Info

Product

Resources

About