Abstract:
PURPOSE:The purpose of this study was to introduce a new algorithm for automated measurement of the modulation transfer function (MTF) using an edge of a readily available phantom and to evaluate the effect of reconstruction filter and field of view (FOV) on the spatial resolution in the CT images. METHODS:Our automated MTF measurement consisted of several steps. The center of the image was established and an appropriate region of interest (ROI) designated. The edge spread function (ESF) was determined, and a suitably interpolated ESF curve was differentiated to obtain the line spread function (LSF). The LSF was Fourier transformed to obtain the MTF. All these steps were accomplished automatically without user intervention. The results of the automated MTF from the edge phantom were validated by comparing them with a point image, and the results of the automated calculation were validated by the standard fitting method. The automated MTF calculation was then applied to the images of two polymethyl methacrylate (PMMA) phantoms and a wire phantom which had been scanned by a Toshiba Alexion 4-slice CT scanner and reconstructed with various filter types and FOVs. RESULTS:The difference in the 50% MTF values obtained from the edge and point phantoms were within ±4%. The values from the automated and fitted methods agreed to within ±2%, indicating that the automated MTF calculation was accurate. The automated MTF calculation was able to differentiate MTF curves for various filters. The spatial resolution values were 0.37 ± 0.00, 0.71 ± 0.01, and 0.78 ± 0.01 cycles/mm for FC13, FC30 and FC52 filters, respectively. The spatial resolution of the images decrease linearly (R2 > 0.98) with increasing FOVs. CONCLUSION:An automated MTF method was successfully developed using an edge phantom, the PMMA phantom. The method is easy to implement in a clinical environment and is not influenced by user experience.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Anam C,Fujibuchi T,Budi WS,Haryanto F,Dougherty Gdoi
10.1002/acm2.12476subject
Has Abstractpub_date
2018-11-01 00:00:00pages
244-252issue
6issn
1526-9914journal_volume
19pub_type
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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更新日期:2009-06-17 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2016-05-08 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2018-11-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2019-06-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
doi:10.1120/jacmp.v1i2.2647
更新日期:2000-04-01 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2016-09-08 00:00:00
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更新日期:2009-10-15 00:00:00
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2017-09-01 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2014-05-08 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2019-10-01 00:00:00