open access
Dose distribution verification for GYN brachytherapy using EBT Gafchromic film and TG-43 calculation
open access
Abstract
Aim
Verification of dose distributions for gynecological (GYN) brachytherapy implants using EBT Gafchromic film.
Background
One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by a treatment planning system.
Materials and methods
A new phantom was designed and fabricated using 90 slabs of 18[[ce:hsp sp="0.25"/]]cm[[ce:hsp sp="0.25"/]]×[[ce:hsp sp="0.25"/]]16[[ce:hsp sp="0.25"/]]cm[[ce:hsp sp="0.25"/]]×[[ce:hsp sp="0.25"/]]0.2[[ce:hsp sp="0.25"/]]cm Perspex to accommodate a tandem and Ovoid assembly, which is normally used for GYN brachytherapy treatment. This phantom design allows the use of EBT Gafchromic films for dosimetric verification of GYN implants with a cobalt-60 HDR system or a LDR Cs-137 system. Gafchromic films were exposed using a plan that was designed to deliver 1.5[[ce:hsp sp="0.25"/]]Gy of dose to 0.5[[ce:hsp sp="0.25"/]]cm distance from the lateral surface of ovoids from a pair of ovoid assembly that was used for treatment vaginal cuff. For a quantitative analysis of the results for both LDR and HDR systems, the measured dose values at several points of interests were compared with the calculated data from a commercially available treatment planning system. This planning system was utilizing the TG-43 formalism and parameters for calculation of dose distributions around a brachytherapy implant.
Results
The results of these investigations indicated that the differences between the calculated and measured data at different points were ranging from 2.4% to 3.8% for the LDR Cs-137 and HDR Co-60 systems, respectively.
Conclusion
The EBT Gafchromic films combined with the newly designed phantom could be utilized for verification of the dose distributions around different GYN implants treated with either LDR or HDR brachytherapy procedures.
Abstract
Aim
Verification of dose distributions for gynecological (GYN) brachytherapy implants using EBT Gafchromic film.
Background
One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by a treatment planning system.
Materials and methods
A new phantom was designed and fabricated using 90 slabs of 18[[ce:hsp sp="0.25"/]]cm[[ce:hsp sp="0.25"/]]×[[ce:hsp sp="0.25"/]]16[[ce:hsp sp="0.25"/]]cm[[ce:hsp sp="0.25"/]]×[[ce:hsp sp="0.25"/]]0.2[[ce:hsp sp="0.25"/]]cm Perspex to accommodate a tandem and Ovoid assembly, which is normally used for GYN brachytherapy treatment. This phantom design allows the use of EBT Gafchromic films for dosimetric verification of GYN implants with a cobalt-60 HDR system or a LDR Cs-137 system. Gafchromic films were exposed using a plan that was designed to deliver 1.5[[ce:hsp sp="0.25"/]]Gy of dose to 0.5[[ce:hsp sp="0.25"/]]cm distance from the lateral surface of ovoids from a pair of ovoid assembly that was used for treatment vaginal cuff. For a quantitative analysis of the results for both LDR and HDR systems, the measured dose values at several points of interests were compared with the calculated data from a commercially available treatment planning system. This planning system was utilizing the TG-43 formalism and parameters for calculation of dose distributions around a brachytherapy implant.
Results
The results of these investigations indicated that the differences between the calculated and measured data at different points were ranging from 2.4% to 3.8% for the LDR Cs-137 and HDR Co-60 systems, respectively.
Conclusion
The EBT Gafchromic films combined with the newly designed phantom could be utilized for verification of the dose distributions around different GYN implants treated with either LDR or HDR brachytherapy procedures.
Keywords
QA brachytherapy phantom; Film dosimetry; GZP6 HDR system; Selectron LDR system; TG-43


Title
Dose distribution verification for GYN brachytherapy using EBT Gafchromic film and TG-43 calculation
Journal
Reports of Practical Oncology and Radiotherapy
Issue
Pages
480-486
Published online
2016-09-01
DOI
10.1016/j.rpor.2016.06.005
Bibliographic record
Rep Pract Oncol Radiother 2016;21(5):480-486.
Keywords
QA brachytherapy phantom
Film dosimetry
GZP6 HDR system
Selectron LDR system
TG-43
Authors
Somayeh Gholami
Hamid Reza Mirzaei
Ali Jabbary Arfaee
Ramin Jaberi
Hassan Ali Nedaie
Seied Rabi Mahdavi
Eftekhar Rajab Bolookat
Ali S. Meigooni