Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer
Introduction: Conventionally, the fattened beam is being used in radiotherapy for routine clinical cases even after introduction of intensity-modulated radiotherapy with incorporation of multi-leaf collimator system. With the removal of the flattening filter (FF) from the beam's path average en...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Wolters Kluwer Medknow Publications
2023-01-01
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| Series: | Journal of Medical Physics |
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| Online Access: | http://www.jmp.org.in/article.asp?issn=0971-6203;year=2023;volume=48;issue=4;spage=338;epage=344;aulast=Kumar |
| _version_ | 1797231822750351360 |
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| author | Arvind Kumar Kiran Sharma Chandi Prasad Bhatt Abhishek Garg |
| author_facet | Arvind Kumar Kiran Sharma Chandi Prasad Bhatt Abhishek Garg |
| author_sort | Arvind Kumar |
| collection | DOAJ |
| description | Introduction: Conventionally, the fattened beam is being used in radiotherapy for routine clinical cases even after introduction of intensity-modulated radiotherapy with incorporation of multi-leaf collimator system. With the removal of the flattening filter (FF) from the beam's path average energy of the photon gets reduced resulting in reduced scatter, reduction in treatment time, and reduced neutron contamination for high-energy beam and ultimately resulting in treatment plan quality deviations. This study aims to investigate the usefulness of the FF-free (FFF) beam for routine head-and-neck cancer (HNC) cases treated with volumetric arc therapy (VMAT) and dosimetrically compares the result with the FF beam. Materials and Methods: In this study, 20 patients treated on HalcyonTM (unmatched 6 megavoltage [6MV] FFF beam) medical linear accelerator with VMAT of different HNC selected and for comparison with 6MV FF beam, 20 equivalent treatment plans are created for TruebeamTM configuration and the plans have been evaluated for target coverage, doses to the organ at risk (OAR), and other dose quality indices. Results: Comparable target coverage, doses to OARs except for rest right parotid (P = 0.02) between 6MV FFF beam and 6MV FF beam is observed. Insignificant differences in conformity index, homogeneity index, and gradient index have been observed. Higher monitor unit (MU) (P ≤ 0.001) and lesser beam on time (BOT) (P = 0.003) have been observed in 6MV FFF. Conclusion: 6MV FFF beam provides comparable target coverage and improved dose-sparing effect to most of the OARs. 6MV FFF beam has lesser BOT, but on the other hand number of MUs is higher as compared to 6MV-FF plans. |
| first_indexed | 2024-04-24T15:50:29Z |
| format | Article |
| id | doaj.art-97d75295262d4c12a2893a409ef14ea5 |
| institution | Directory Open Access Journal |
| issn | 0971-6203 1998-3913 |
| language | English |
| last_indexed | 2024-04-24T15:50:29Z |
| publishDate | 2023-01-01 |
| publisher | Wolters Kluwer Medknow Publications |
| record_format | Article |
| series | Journal of Medical Physics |
| spelling | doaj.art-97d75295262d4c12a2893a409ef14ea52024-04-01T12:49:17ZengWolters Kluwer Medknow PublicationsJournal of Medical Physics0971-62031998-39132023-01-0148433834410.4103/jmp.jmp_68_23Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancerArvind KumarKiran SharmaChandi Prasad BhattAbhishek GargIntroduction: Conventionally, the fattened beam is being used in radiotherapy for routine clinical cases even after introduction of intensity-modulated radiotherapy with incorporation of multi-leaf collimator system. With the removal of the flattening filter (FF) from the beam's path average energy of the photon gets reduced resulting in reduced scatter, reduction in treatment time, and reduced neutron contamination for high-energy beam and ultimately resulting in treatment plan quality deviations. This study aims to investigate the usefulness of the FF-free (FFF) beam for routine head-and-neck cancer (HNC) cases treated with volumetric arc therapy (VMAT) and dosimetrically compares the result with the FF beam. Materials and Methods: In this study, 20 patients treated on HalcyonTM (unmatched 6 megavoltage [6MV] FFF beam) medical linear accelerator with VMAT of different HNC selected and for comparison with 6MV FF beam, 20 equivalent treatment plans are created for TruebeamTM configuration and the plans have been evaluated for target coverage, doses to the organ at risk (OAR), and other dose quality indices. Results: Comparable target coverage, doses to OARs except for rest right parotid (P = 0.02) between 6MV FFF beam and 6MV FF beam is observed. Insignificant differences in conformity index, homogeneity index, and gradient index have been observed. Higher monitor unit (MU) (P ≤ 0.001) and lesser beam on time (BOT) (P = 0.003) have been observed in 6MV FFF. Conclusion: 6MV FFF beam provides comparable target coverage and improved dose-sparing effect to most of the OARs. 6MV FFF beam has lesser BOT, but on the other hand number of MUs is higher as compared to 6MV-FF plans.http://www.jmp.org.in/article.asp?issn=0971-6203;year=2023;volume=48;issue=4;spage=338;epage=344;aulast=Kumar6 megavoltage flattening filter beamflattening filter freehead-and-neck cancerunmatched 6 megavoltage flattening filter-free beamvolumetric arc therapy |
| spellingShingle | Arvind Kumar Kiran Sharma Chandi Prasad Bhatt Abhishek Garg Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer Journal of Medical Physics 6 megavoltage flattening filter beam flattening filter free head-and-neck cancer unmatched 6 megavoltage flattening filter-free beam volumetric arc therapy |
| title | Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer |
| title_full | Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer |
| title_fullStr | Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer |
| title_full_unstemmed | Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer |
| title_short | Dosimetric comparison of unmatched flattening filter-free and flattened beams in volumetric arc therapy plans for head-and-neck cancer |
| title_sort | dosimetric comparison of unmatched flattening filter free and flattened beams in volumetric arc therapy plans for head and neck cancer |
| topic | 6 megavoltage flattening filter beam flattening filter free head-and-neck cancer unmatched 6 megavoltage flattening filter-free beam volumetric arc therapy |
| url | http://www.jmp.org.in/article.asp?issn=0971-6203;year=2023;volume=48;issue=4;spage=338;epage=344;aulast=Kumar |
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