Show simple item record

dc.contributor.authorNajem, MA
dc.contributor.authorTedder, M
dc.contributor.authorKing, D
dc.contributor.authorBernstein, D
dc.contributor.authorTrouncer, R
dc.contributor.authorMeehan, C
dc.contributor.authorBidmead, AM
dc.date.accessioned2019-06-27T11:30:17Z
dc.date.issued2018-08-02
dc.identifier.citationPhysica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB), 2018, 52 pp. 143 - 153
dc.identifier.issn1120-1797
dc.identifier.urihttps://repository.icr.ac.uk/handle/internal/3279
dc.identifier.eissn1724-191X
dc.identifier.doi10.1016/j.ejmp.2018.07.010
dc.description.abstractWe have adapted the methodology of Berry et al. (2012) for Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) treatments at a fixed source to imager distance (SID) based on the manufacturer's through-air portal dose image prediction algorithm. In order to fix the SID a correction factor was introduced to account for the change in air gap between patient and imager. Commissioning data, collected with multiple field sizes, solid water thicknesses and air gaps, were acquired at 150 cm SID on the Varian aS1200 EPID. The method was verified using six IMRT and seven VMAT plans on up to three different phantoms. The method's sensitivity and accuracy were investigated by introducing errors. A global 3%/3 mm gamma was used to assess the differences between the predicted and measured portal dose images. The effect of a varying air gap on EPID signal was found to be significant - varying by up to 30% with field size, phantom thickness, and air gap. All IMRT plans passed the 3%/3 mm gamma criteria by more than 95% on the three phantoms. 23 of 24 arcs from the VMAT plans passed the 3%/3 mm gamma criteria by more than 95%. This method was found to be sensitive to a range of potential errors. The presented approach provides fast and accurate in-vivo EPID dosimetry for IMRT and VMAT treatments and can potentially replace many pre-treatment verifications.
dc.formatPrint-Electronic
dc.format.extent143 - 153
dc.languageeng
dc.language.isoeng
dc.rights.urihttps://creativecommons.org/licenses/by/4.0
dc.subjectHumans
dc.subjectWater
dc.subjectRadiometry
dc.subjectPhantoms, Imaging
dc.subjectAir
dc.subjectAlgorithms
dc.subjectModels, Anatomic
dc.subjectRadiotherapy, Intensity-Modulated
dc.titleIn-vivo EPID dosimetry for IMRT and VMAT based on through-air predicted portal dose algorithm.
dc.typeJournal Article
dcterms.dateAccepted2018-07-24
rioxxterms.versionofrecord10.1016/j.ejmp.2018.07.010
rioxxterms.licenseref.urihttps://creativecommons.org/licenses/by/4.0
rioxxterms.licenseref.startdate2018-08-02
rioxxterms.typeJournal Article/Review
dc.relation.isPartOfPhysica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)
pubs.notesNot known
pubs.organisational-group/ICR
pubs.organisational-group/ICR/Primary Group
pubs.organisational-group/ICR/Primary Group/ICR Divisions
pubs.organisational-group/ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging
pubs.organisational-group/ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radiotherapy Physics Modelling
pubs.organisational-group/ICR
pubs.organisational-group/ICR/Primary Group
pubs.organisational-group/ICR/Primary Group/ICR Divisions
pubs.organisational-group/ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging
pubs.organisational-group/ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radiotherapy Physics Modelling
pubs.publication-statusPublished
pubs.volume52
pubs.embargo.termsNot known
icr.researchteamRadiotherapy Physics Modellingen_US
dc.contributor.icrauthorBernstein, Daviden


Files in this item

Thumbnail

This item appears in the following collection(s)

Show simple item record

https://creativecommons.org/licenses/by/4.0
Except where otherwise noted, this item's license is described as https://creativecommons.org/licenses/by/4.0