Abstract：
:Magnetic Resonance Imaging (MRI) is increasingly being used for improving tumor delineation and tumor tracking in the presence of respiratory motion. The purpose of this work is to design and build an MR compatible motion platform and to use it for evaluating the geometric accuracy of MR imaging techniques during respiratory motion. The motion platform presented in this work is composed of a mobile base made up of a flat plate and four wheels. The mobile base is attached from one end and through a rigid rod to a synchrony motion table by Accuray® placed at the end of the MRI table and from the other end to an elastic rod. The geometric accuracy was measured by placing a control point-based phantom on top of the mobile base. In-house software module was used to automatically assess the geometric distortion. The blurring artifact was also assessed by measuring the Full Width Half Maximum (FWHM) of each control point. Our results were assessed for 50, 100, and 150 mm radial distances, with a mean geometric distortion during the superior-inferior motion of 0.27, 0.41, and 0.55 mm, respectively. Adding the anterior-posterior motion, the mean geometric distortions increased to 0.4, 0.6, and 0.8 mm. Blurring was observed during motion causing an increase in the FWHM of ≈30%. The platform presented in this work provides a valuable tool for the assessment of the geometric accuracy and blurring artifact for MR during motion. Although the main objective was to test the spatial accuracy of an MR system during motion, the modular aspect of the presented platform enables the use of any commercially available phantom for a full quality control of the MR system during motion.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Torfeh T,Hammoud R,El Kaissi T,McGarry M,Aouadi S,Fayad H,Al-Hammadi Ndoi
10.1002/acm2.12274subject
Has Abstractpub_date
2018-03-01 00:00:00pages
168-175issue
2issn
1526-9914journal_volume
19pub_type
杂志文章abstract：:Magnetic resonance imaging (MRI) is regularly used for stereotactic imaging of Gamma Knife (GK) radiosurgery patients for GK treatment planning. MRI-induced thermal injuries have occurred and been reported for GK patients with attached metallic headframes. Depending on the specific MR imaging and headframe conditions,...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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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：2015-05-08 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：2002-07-01 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2020-07-01 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：2019-08-01 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：2017-01-01 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：2018-05-01 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.v10i1.2772
更新日期：2009-02-05 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：2018-11-01 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2008-07-14 00:00:00
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更新日期：2013-09-06 00:00:00
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更新日期：2014-07-08 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：2013-01-07 00:00:00
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更新日期：2014-01-06 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：2020-10-27 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2016-03-08 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：2020-12-20 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2012-05-10 00:00:00
