Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator
Background and purpose: A commercial 2.5 MV beam has been clinically available for beam’s-eye-view imaging in radiotherapy, offering improved contrast-to-noise ratio (CNR) compared to therapeutic beams, due to the softer spectrum. Previous research suggested that imaging performance could be improve...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2020-10-01
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| Series: | Physics and Imaging in Radiation Oncology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2405631620300701 |
| _version_ | 1818594413741342720 |
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| author | Jennifer M. Borsavage Amanda Cherpak James L. Robar |
| author_facet | Jennifer M. Borsavage Amanda Cherpak James L. Robar |
| author_sort | Jennifer M. Borsavage |
| collection | DOAJ |
| description | Background and purpose: A commercial 2.5 MV beam has been clinically available for beam’s-eye-view imaging in radiotherapy, offering improved contrast-to-noise ratio (CNR) compared to therapeutic beams, due to the softer spectrum. Previous research suggested that imaging performance could be improved using a low-Z diamond target to reduce the self-absorption of diagnostic energy photons. The aim of this study was to 1) investigate the feasibility of two 2.5 MV diamond target beamline configurations and 2) characterize the dosimetry and planar image quality of these novel low-Z beams. Materials and methods: The commercial 2.5 MV beam was modified by replacing the copper target with sintered diamond. Two beamlines were investigated: a carousel-mounted diamond target beamline and a ‘conventional’ beamline, with the diamond target in the target arm. Planar image quality was assessed in terms of spatial resolution and CNR. Results: Due to image artifacts, image quality could not be assessed for the carousel-mounted low-Z target beam. The ‘conventional’ 2.5 MV low-Z beam quality was softer by 2.7% compared to the commercial imaging beam, resulting in improved CNR by factors of up to 1.3 and 1.7 in thin and thick phantoms, respectively. In regard to spatial resolution, the ‘conventional’ 2.5 MV low-Z beam slightly outperformed the commercial imaging beam. Conclusion: With a simple modification to the 2.5 MV commercial beamline, we produced an improved energy spectrum for imaging. This 2.5 MV diamond target beam proved to be an advantageous alternative to the commercial target configuration, offering both superior resolution and CNR. |
| first_indexed | 2024-12-16T10:59:44Z |
| format | Article |
| id | doaj.art-07e51d57b4b84163bdb575ff2112e7bd |
| institution | Directory Open Access Journal |
| issn | 2405-6316 |
| language | English |
| last_indexed | 2024-12-16T10:59:44Z |
| publishDate | 2020-10-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Physics and Imaging in Radiation Oncology |
| spelling | doaj.art-07e51d57b4b84163bdb575ff2112e7bd2022-12-21T22:34:02ZengElsevierPhysics and Imaging in Radiation Oncology2405-63162020-10-0116103108Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear acceleratorJennifer M. Borsavage0Amanda Cherpak1James L. Robar2Dalhousie University, Department of Physics and Atmospheric Science, 5820 University Ave., Halifax, Nova Scotia B3H 1V7, Canada; Corresponding author.Dalhousie University, Department of Physics and Atmospheric Science, 5820 University Ave., Halifax, Nova Scotia B3H 1V7, Canada; Dalhousie University, Department of Radiation Oncology, 5820 University Ave., Halifax, Nova Scotia B3H 1V7, Canada; Nova Scotia Health Authority, Department of Medical Physics, Halifax, CanadaDalhousie University, Department of Physics and Atmospheric Science, 5820 University Ave., Halifax, Nova Scotia B3H 1V7, Canada; Dalhousie University, Department of Radiation Oncology, 5820 University Ave., Halifax, Nova Scotia B3H 1V7, Canada; Nova Scotia Health Authority, Department of Medical Physics, Halifax, CanadaBackground and purpose: A commercial 2.5 MV beam has been clinically available for beam’s-eye-view imaging in radiotherapy, offering improved contrast-to-noise ratio (CNR) compared to therapeutic beams, due to the softer spectrum. Previous research suggested that imaging performance could be improved using a low-Z diamond target to reduce the self-absorption of diagnostic energy photons. The aim of this study was to 1) investigate the feasibility of two 2.5 MV diamond target beamline configurations and 2) characterize the dosimetry and planar image quality of these novel low-Z beams. Materials and methods: The commercial 2.5 MV beam was modified by replacing the copper target with sintered diamond. Two beamlines were investigated: a carousel-mounted diamond target beamline and a ‘conventional’ beamline, with the diamond target in the target arm. Planar image quality was assessed in terms of spatial resolution and CNR. Results: Due to image artifacts, image quality could not be assessed for the carousel-mounted low-Z target beam. The ‘conventional’ 2.5 MV low-Z beam quality was softer by 2.7% compared to the commercial imaging beam, resulting in improved CNR by factors of up to 1.3 and 1.7 in thin and thick phantoms, respectively. In regard to spatial resolution, the ‘conventional’ 2.5 MV low-Z beam slightly outperformed the commercial imaging beam. Conclusion: With a simple modification to the 2.5 MV commercial beamline, we produced an improved energy spectrum for imaging. This 2.5 MV diamond target beam proved to be an advantageous alternative to the commercial target configuration, offering both superior resolution and CNR.http://www.sciencedirect.com/science/article/pii/S2405631620300701Low-Z targetBeam’s eye view imagingDiamond targetPlanar imagingMV imaging |
| spellingShingle | Jennifer M. Borsavage Amanda Cherpak James L. Robar Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator Physics and Imaging in Radiation Oncology Low-Z target Beam’s eye view imaging Diamond target Planar imaging MV imaging |
| title | Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator |
| title_full | Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator |
| title_fullStr | Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator |
| title_full_unstemmed | Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator |
| title_short | Investigation of planar image quality for a novel 2.5 MV diamond target beam from a radiotherapy linear accelerator |
| title_sort | investigation of planar image quality for a novel 2 5 mv diamond target beam from a radiotherapy linear accelerator |
| topic | Low-Z target Beam’s eye view imaging Diamond target Planar imaging MV imaging |
| url | http://www.sciencedirect.com/science/article/pii/S2405631620300701 |
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