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Evaluation of 4D CT acquisition methods designed to reduce artifacts

Four‐dimensional computed tomography (4D CT) is used to account for respiratory motion in radiation treatment planning, but artifacts resulting from the acquisition and postprocessing limit its accuracy. We investigated the efficacy of three experimental 4D CT acquisition methods to reduce artifacts...

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Detalles Bibliográficos
Autores principales: Castillo, Sarah J., Castillo, Richard, Castillo, Edward, Pan, Tinsu, Ibbott, Geoffrey, Balter, Peter, Hobbs, Brian, Guerrero, Thomas
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4504190/
https://www.ncbi.nlm.nih.gov/pubmed/26103169
http://dx.doi.org/10.1120/jacmp.v16i2.4949
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author Castillo, Sarah J.
Castillo, Richard
Castillo, Edward
Pan, Tinsu
Ibbott, Geoffrey
Balter, Peter
Hobbs, Brian
Guerrero, Thomas
author_facet Castillo, Sarah J.
Castillo, Richard
Castillo, Edward
Pan, Tinsu
Ibbott, Geoffrey
Balter, Peter
Hobbs, Brian
Guerrero, Thomas
author_sort Castillo, Sarah J.
collection PubMed
description Four‐dimensional computed tomography (4D CT) is used to account for respiratory motion in radiation treatment planning, but artifacts resulting from the acquisition and postprocessing limit its accuracy. We investigated the efficacy of three experimental 4D CT acquisition methods to reduce artifacts in a prospective institutional review board approved study. Eighteen thoracic patients scheduled to undergo radiation therapy received standard clinical 4D CT scans followed by each of the alternative 4D CT acquisitions: 1) data oversampling, 2) beam gating with breathing irregularities, and 3) rescanning the clinical acquisition acquired during irregular breathing. Relative values of a validated correlation‐based artifact metric (CM) determined the best acquisition method per patient. Each 4D CT was processed by an extended phase sorting approach that optimizes the quantitative artifact metric (CM sorting). The clinical acquisitions were also postprocessed by phase sorting for artifact comparison of our current clinical implementation with the experimental methods. The oversampling acquisition achieved the lowest artifact presence among all acquisitions, achieving a 27% reduction from the current clinical 4D CT implementation ([Formula: see text]). The rescan method presented a significantly higher artifact presence from the clinical acquisition (37%; [Formula: see text]), the gating acquisition (26%; [Formula: see text]), and the oversampling acquisition (31%; [Formula: see text]), while the data lacked evidence of a significant difference between the clinical, gating, and oversampling methods. The oversampling acquisition reduced artifact presence from the current clinical 4D CT implementation to the largest degree and provided the simplest and most reproducible implementation. The rescan acquisition increased artifact presence significantly, compared to all acquisitions, and suffered from combination of data from independent scans over which large internal anatomic shifts occurred. PACS numbers: 87.57.C‐, 87.57.cp, 87.57.Q‐, 87.55.Gh
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spelling pubmed-45041902018-04-02 Evaluation of 4D CT acquisition methods designed to reduce artifacts Castillo, Sarah J. Castillo, Richard Castillo, Edward Pan, Tinsu Ibbott, Geoffrey Balter, Peter Hobbs, Brian Guerrero, Thomas J Appl Clin Med Phys Radiation Oncology Physics Four‐dimensional computed tomography (4D CT) is used to account for respiratory motion in radiation treatment planning, but artifacts resulting from the acquisition and postprocessing limit its accuracy. We investigated the efficacy of three experimental 4D CT acquisition methods to reduce artifacts in a prospective institutional review board approved study. Eighteen thoracic patients scheduled to undergo radiation therapy received standard clinical 4D CT scans followed by each of the alternative 4D CT acquisitions: 1) data oversampling, 2) beam gating with breathing irregularities, and 3) rescanning the clinical acquisition acquired during irregular breathing. Relative values of a validated correlation‐based artifact metric (CM) determined the best acquisition method per patient. Each 4D CT was processed by an extended phase sorting approach that optimizes the quantitative artifact metric (CM sorting). The clinical acquisitions were also postprocessed by phase sorting for artifact comparison of our current clinical implementation with the experimental methods. The oversampling acquisition achieved the lowest artifact presence among all acquisitions, achieving a 27% reduction from the current clinical 4D CT implementation ([Formula: see text]). The rescan method presented a significantly higher artifact presence from the clinical acquisition (37%; [Formula: see text]), the gating acquisition (26%; [Formula: see text]), and the oversampling acquisition (31%; [Formula: see text]), while the data lacked evidence of a significant difference between the clinical, gating, and oversampling methods. The oversampling acquisition reduced artifact presence from the current clinical 4D CT implementation to the largest degree and provided the simplest and most reproducible implementation. The rescan acquisition increased artifact presence significantly, compared to all acquisitions, and suffered from combination of data from independent scans over which large internal anatomic shifts occurred. PACS numbers: 87.57.C‐, 87.57.cp, 87.57.Q‐, 87.55.Gh John Wiley and Sons Inc. 2015-03-08 /pmc/articles/PMC4504190/ /pubmed/26103169 http://dx.doi.org/10.1120/jacmp.v16i2.4949 Text en © 2015 The Authors. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/3.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Radiation Oncology Physics
Castillo, Sarah J.
Castillo, Richard
Castillo, Edward
Pan, Tinsu
Ibbott, Geoffrey
Balter, Peter
Hobbs, Brian
Guerrero, Thomas
Evaluation of 4D CT acquisition methods designed to reduce artifacts
title Evaluation of 4D CT acquisition methods designed to reduce artifacts
title_full Evaluation of 4D CT acquisition methods designed to reduce artifacts
title_fullStr Evaluation of 4D CT acquisition methods designed to reduce artifacts
title_full_unstemmed Evaluation of 4D CT acquisition methods designed to reduce artifacts
title_short Evaluation of 4D CT acquisition methods designed to reduce artifacts
title_sort evaluation of 4d ct acquisition methods designed to reduce artifacts
topic Radiation Oncology Physics
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4504190/
https://www.ncbi.nlm.nih.gov/pubmed/26103169
http://dx.doi.org/10.1120/jacmp.v16i2.4949
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