Abstract：
INTRODUCTION:Increased modulation and dynamical delivery of external beam radiotherapy (EBRT), such as volumetric modulated arc therapy (VMAT) with dynamic gantry rotation, continuously variable dose rate (CVDR) and field shapes that change during the beam, place greater demands on the performance of linear accelerators (linac). In this study, the accuracy of the linac beam steering is improved by the application of a new method to determine the gantry-dependent lookup table. METHODS:An improved method of lookup table creation based on service graphing information from the linac is investigated. This minimizes the impact of magnetic hysteresis due to the previous current in the steering magnets, which is dependent on the previous gantry angle. A software tool, programmed with MATLAB®, is used to calculate and export the new optimal lookup table (LUT). RESULTS:This method is efficient requiring little clinical machine time or analysis time, and leads to an improved VMAT delivery with a reduction of about 60 percent in beam steering errors. If the surrounding magnetic field is changed, for example, ramping a nearby magnetic resonance imaging system (MRI), the beam steering LUT optimization can be quickly performed. CONCLUSION:This study shows an improved linac stability using improved lookup tables. Resulting in a lower number of interruptions, preventing down-time, and a lower risk of intrafraction motion due to longer treatment times.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
van Appeldoorn AA,Kok JGM,Wolthaus JWHdoi
10.1002/acm2.13047subject
Has Abstractpub_date
2020-10-23 00:00:00issn
1526-9914pub_type
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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
pub_type： 杂志文章
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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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pub_type： 杂志文章
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journal_title：Journal of applied clinical medical physics
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doi：10.1120/jacmp.v3i4.2554
更新日期：2002-10-01 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.v15i6.5035
更新日期：2014-11-08 00:00:00
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doi：10.1120/jacmp.v14i6.4382
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doi：10.1120/jacmp.v17i5.6237
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：
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pub_type： 杂志文章,随机对照试验
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pub_type： 临床试验,杂志文章
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journal_title：Journal of applied clinical medical physics
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更新日期：2020-05-01 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2002-07-01 00:00:00
abstract：:Part II of this review article presents four case studies for which peak skin doses are calculated following the methods outlined in Part I of this review. The data available in the cases ranges from proprietary dose reports to fluoroscopy time and number of digital acquisition frames only. Flowcharts are provided for...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2012-01-05 00:00:00
