Show simple item record

dc.contributor.authorGislason-Lee, Amber J.*
dc.contributor.authorTunstall, C.M.*
dc.contributor.authorKengyelics, S.K.*
dc.contributor.authorCowen, A.R.*
dc.contributor.authorDavies, A.G.*
dc.date.accessioned2019-04-16T14:45:28Z
dc.date.available2019-04-16T14:45:28Z
dc.date.issued2015-08
dc.identifier.citationGislason-Lee AJ, Tunstall CM, Kengyelics SK et al (2015) Technical Note: Impact on detective quantum efficiency of edge angle determination method by International Electrotechnical Commission methodology for cardiac x-ray image detectors. Medical Physics. 42(8): 4423-4427.en_US
dc.identifier.urihttp://hdl.handle.net/10454/16973
dc.descriptionNoen_US
dc.description.abstractPurpose: Cardiac x-ray detectors are used to acquire moving images in real-time for angiography and interventional procedures. Detective quantum efficiency (DQE) is not generally measured on these dynamic detectors; the required “for processing” image data and control of x-ray settings have not been accessible. By 2016, USA hospital physicists will have the ability to measure DQE and will likely utilize the International Electrotechnical Commission (IEC) standard for measuring DQE of dynamic x-ray imaging devices. The current IEC standard requires an image of a tilted tungsten edge test object to obtain modulation transfer function (MTF) for DQE calculation. It specifies the range of edge angles to use; however, it does not specify a preferred method to determine this angle for image analysis. The study aimed to answer the question “will my choice in method impact my results?” Four different established edge angle determination methods were compared to investigate the impact on DQE. Methods: Following the IEC standard, edge and flat field images were acquired on a cardiac flat-panel detector to calculate MTF and noise power spectrum, respectively, to determine DQE. Accuracy of the methods in determining the correct angle was ascertained using a simulated edge image with known angulations. Precision of the methods was ascertained using variability of MTF and DQE, calculated via bootstrapping. Results: Three methods provided near equal angles and the same MTF while the fourth, with an angular difference of 6%, had a MTF lower by 3% at 1.5 mm−1 spatial frequency and 8% at 2.5 mm−1; corresponding DQE differences were 6% at 1.5 mm−1 and 17% at 2.5 mm−1; differences were greater than standard deviations in the measurements. Conclusions: DQE measurements may vary by a significant amount, depending on the method used to determine the edge angle when following the IEC standard methodology for a cardiac x-ray detector. The most accurate and precise methods are recommended for absolute assessments and reproducible measurements, respectively.en_US
dc.description.sponsorshipFunded by Philips Healthcare, NL, and a University of Leeds Career Development Bursery.en_US
dc.language.isoenen_US
dc.relation.isreferencedbyhttps://doi.org/10.1118/1.4923178en_US
dc.subjectModulation transfer functionen_US
dc.subjectDetective quantum efficiencyen_US
dc.subjectX-rayen_US
dc.subjectFluoroscopyen_US
dc.subjectDigital radiographyen_US
dc.titleTechnical Note: Impact on detective quantum efficiency of edge angle determination method by International Electrotechnical Commission methodology for cardiac x-ray image detectorsen_US
dc.status.refereedYesen_US
dc.date.Accepted2015-06-16
dc.date.application2015-07-02
dc.typeArticleen_US
dc.type.versionNo full-text in the repositoryen_US


This item appears in the following Collection(s)

Show simple item record