Limits...
Monte Carlo dosimetry of a new (90)Y brachytherapy source.

Junxiang W, Shihu Y, Jing H, Fengxiang L, Chengkai W, Zhangwen W, Qing H, Chengjun G - J Contemp Brachytherapy (2015)

Bottom Line: The active core length of the new (90)Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old (90)Sr/(90)Y source.The reference absorbed dose rate for the new (90)Y source was determined to be equal to 1.6608 ± 0.0008 cGy s(-1) mCi(-1), compared to the values of 0.9063 ± 0.0005 cGy s(-1) mCi(-1) that were calculated for the old (90)Sr/(90)Y source.These data are meant to be used commercially in after-loading system.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Radiation Physics and Technology, Ministry of Education and Institute of Nuclear Science and Technology, Sichuan University.

ABSTRACT

Purpose: In this study, we attempted to obtain full dosimetric data for a new (90)Y brachytherapy source developed by the College of Chemistry (Sichuan University) for use in high-dose-rate after-loading systems.

Material and methods: The dosimetric data for this new source were used as required by the dose calculation formalisms proposed by the AAPM Task Group 60 and Task Group 149. The active core length of the new (90)Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old (90)Sr/(90)Y source. The Monte Carlo simulation toolkit Geant4 was used to calculate these parameters. The source was located in a 30-cm-radius theoretical sphere water phantom.

Results: The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 1.0 to 8.0 mm in the longitudinal axis, and the anisotropy function with a θ in the range of 0° to 90° at 5° intervals and an r in the range of 1.0 to 8.0 mm in 0.2-mm intervals. The reference absorbed dose rate for the new (90)Y source was determined to be equal to 1.6608 ± 0.0008 cGy s(-1) mCi(-1), compared to the values of 0.9063 ± 0.0005 cGy s(-1) mCi(-1) that were calculated for the old (90)Sr/(90)Y source. A polynomial function was also obtained for the radial dose function by curve fitting.

Conclusions: Dosimetric data are provided for the new (90)Y brachytherapy source. These data are meant to be used commercially in after-loading system.

No MeSH data available.


Related in: MedlinePlus

Longitudinal view of new 90Y (mm)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4663217&req=5

Figure 0001: Longitudinal view of new 90Y (mm)

Mentions: The source design, materials and sizes are presented in Figure 1. The design of the new 90Y source was provided by the College of Chemistry (Sichuan University), and the tolerances of this new source were ± 0.01 mm provided by manufacturer. The basic sizes and materials of the core and capsules used in the simulation were taken as follows: the composition of the liquid 90Y core was assumed to be H2O with a density of 1.0 g/cm3, and the radioactive material was uniformly distributed in its core. The active core was encapsulated. The capsule material was polyethylene (PE, 86% carbon and 14% hydrogen) with an effective density of 0.94 g/cm3 as shown in Table 1. The active length of the new source was 4.7 mm. At the center of the capsule was a cylinder 4.2 mm in length, 0.8 mm in outer diameter, and 0.5 mm in inner diameter, with two semispherical endings with 0.8 mm external diameters and 0.5 mm inner diameters on the top and the bottom of the cylindrical capsule. The thickness of the PE capsule was 0.15 mm at the cylindrical core.


Monte Carlo dosimetry of a new (90)Y brachytherapy source.

Junxiang W, Shihu Y, Jing H, Fengxiang L, Chengkai W, Zhangwen W, Qing H, Chengjun G - J Contemp Brachytherapy (2015)

Longitudinal view of new 90Y (mm)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4663217&req=5

Figure 0001: Longitudinal view of new 90Y (mm)
Mentions: The source design, materials and sizes are presented in Figure 1. The design of the new 90Y source was provided by the College of Chemistry (Sichuan University), and the tolerances of this new source were ± 0.01 mm provided by manufacturer. The basic sizes and materials of the core and capsules used in the simulation were taken as follows: the composition of the liquid 90Y core was assumed to be H2O with a density of 1.0 g/cm3, and the radioactive material was uniformly distributed in its core. The active core was encapsulated. The capsule material was polyethylene (PE, 86% carbon and 14% hydrogen) with an effective density of 0.94 g/cm3 as shown in Table 1. The active length of the new source was 4.7 mm. At the center of the capsule was a cylinder 4.2 mm in length, 0.8 mm in outer diameter, and 0.5 mm in inner diameter, with two semispherical endings with 0.8 mm external diameters and 0.5 mm inner diameters on the top and the bottom of the cylindrical capsule. The thickness of the PE capsule was 0.15 mm at the cylindrical core.

Bottom Line: The active core length of the new (90)Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old (90)Sr/(90)Y source.The reference absorbed dose rate for the new (90)Y source was determined to be equal to 1.6608 ± 0.0008 cGy s(-1) mCi(-1), compared to the values of 0.9063 ± 0.0005 cGy s(-1) mCi(-1) that were calculated for the old (90)Sr/(90)Y source.These data are meant to be used commercially in after-loading system.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Radiation Physics and Technology, Ministry of Education and Institute of Nuclear Science and Technology, Sichuan University.

ABSTRACT

Purpose: In this study, we attempted to obtain full dosimetric data for a new (90)Y brachytherapy source developed by the College of Chemistry (Sichuan University) for use in high-dose-rate after-loading systems.

Material and methods: The dosimetric data for this new source were used as required by the dose calculation formalisms proposed by the AAPM Task Group 60 and Task Group 149. The active core length of the new (90)Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old (90)Sr/(90)Y source. The Monte Carlo simulation toolkit Geant4 was used to calculate these parameters. The source was located in a 30-cm-radius theoretical sphere water phantom.

Results: The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 1.0 to 8.0 mm in the longitudinal axis, and the anisotropy function with a θ in the range of 0° to 90° at 5° intervals and an r in the range of 1.0 to 8.0 mm in 0.2-mm intervals. The reference absorbed dose rate for the new (90)Y source was determined to be equal to 1.6608 ± 0.0008 cGy s(-1) mCi(-1), compared to the values of 0.9063 ± 0.0005 cGy s(-1) mCi(-1) that were calculated for the old (90)Sr/(90)Y source. A polynomial function was also obtained for the radial dose function by curve fitting.

Conclusions: Dosimetric data are provided for the new (90)Y brachytherapy source. These data are meant to be used commercially in after-loading system.

No MeSH data available.


Related in: MedlinePlus