Abstract：
:The assessment of the coincidence of imaging and radiation isocenters is an important task of regular quality assurance of medical linear accelerators (linacs) as recommended in national and international quality assurance guidelines. A previously reported investigation of the accuracy of the Elekta XVI software to localize the linac radiation isocenter, by comparing statistically with other independent software, has shown some discrepancies at the sub-mm level. A further investigation is carried out here using a set of reference images and mathematical operations to observe how the Elekta XVI software analyses them. Symmetric mathematical operations on reference images should result in symmetrical outcomes. Three different rotation functions are used in increasing degree of complexity to characterize the Elekta XVI software error in the linac radiation isocenter position. No independent algorithms or phantoms are used in this methodology. The magnitude and direction of the radiation isocenter localization error has been determined to be consistently 0.13 mm or 0.14 mm in the longitudinal direction towards the target depending on the case. The radiation isocenter localization error comprises two separated errors of the Ball Bearing Center by 0.13 mm and MV Field Center by either 0.00 mm or -0.01 mm in the longitudinal direction towards the target. The calculation of the MV Field Center is influenced by the polymethyl methacrylate rod supporting the ball-bearing. The precise value and the root cause of the error cannot be assessed due to the rounding effect of the results reported by the Elekta XVI software and lack of access to the source code.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Chojnowski JM,Warr GB,Sykes JR,Thwaites DIdoi
10.1002/acm2.12861subject
Has Abstractpub_date
2020-05-01 00:00:00pages
93-97issue
5issn
1526-9914journal_volume
21pub_type
杂志文章abstract：:To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherap...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12121
更新日期：2017-09-01 00:00:00
abstract：PURPOSE:The target detectability of cone beam computed tomography (CBCT) performed in image-guided radiation therapy (IGRT) was investigated to achieve sufficient image quality for patient positioning over a course of treatment session while maintaining radiation exposure from CBCT imaging as low as reasonably achievab...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12306
更新日期：2018-05-01 00:00:00
abstract：:The QFix EncompassTM stereotactic radiosurgery (SRS) immobilization system consists of a thermoplastic mask that attaches to the couch insert to immobilize patients treated with intracranial SRS. This study evaluates the dosimetric impact and verifies a vendor provided treatment planning system (TPS) model in the Ecli...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12387
更新日期：2018-07-01 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.v15i1.4095
更新日期：2014-01-06 00:00:00
abstract：:Physical and dosimetric characteristics of HDMLC were studied for SRS6, 6, and 10 MV X-rays from Novalis Tx. This in-built tertiary collimator consists of 60 pairs (32 × 0.25 cm; 26 × 0.5 cm and 2 × 0.7 cm) of leaves. Properties of HDMLC studied included alignment, readout and radiation field congruence, radiation pen...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v12i3.3475
更新日期：2011-04-14 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.v3i2.2580
更新日期：2002-04-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12718
更新日期：2019-10-01 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.v17i5.6148
更新日期：2016-09-08 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.v15i5.4844
更新日期：2014-09-08 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.v15i5.4696
更新日期：2014-09-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12165
更新日期：2017-09-01 00:00:00
abstract：:We have investigated the combined effect of tissue heterogeneity and its variation associated with geometric error in stereotactic body radiotherapy (SBRT) for lung cancer. The treatment plans for eight lung cancer patients were calculated using effective path length (EPL) correction and Monte Carlo (MC) algorithms, w...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i5.5397
更新日期：2015-09-08 00:00:00
abstract：:The aim of this study was to assess the performance of a gantry-mounted detector system and a couch set detector system using a systematic multileaf collimator positional error manually introduced for volumetric-modulated arc therapy. Four head and neck and esophagus VMAT plans were evaluated by measurement using an e...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v15i3.4495
更新日期：2014-05-08 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.v7i4.2222
更新日期：2006-11-28 00:00:00
abstract：:The assessment of intracranial aneurysms is increasingly performed using three-dimensional cone-beam rotational angiography (3D CBRA). To reduce the dose to the patient during 3D CBRA procedures, filtered region-of-interest imaging (FROI) is presented in literature to be an effective technique as the dose in regions o...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i2.5306
更新日期：2015-03-08 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.v16i4.5350
更新日期：2015-07-08 00:00:00
abstract：:A custom-made computer program, SWIMRT, to construct "multileaf collimator (MLC) machine" file for intensity-modulated radiotherapy (IMRT) fluence maps was developed using MATLAB and the sliding window algorithm. The user can either import a fluence map with a graphical file format created by an external treatment-pla...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v7i2.2231
更新日期：2006-05-25 00:00:00
abstract：PURPOSE:Prescription practice in SRS plans for brain tumors differs significantly for different modalities. In this retrospective study, the strategies to optimize SRS plans for brain tumors with volumetric arc therapy (VMAT) were presented. METHODS:Fifty clinically treated cases were stratified by the maximum target ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12818
更新日期：2020-03-01 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.v15i5.4931
更新日期：2014-09-08 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：2018-11-01 00:00:00
abstract：:The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States. The...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i5.5768
更新日期：2015-09-08 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12895
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
doi：10.1120/jacmp.v2i3.2607
更新日期：2001-07-01 00:00:00
abstract：BACKGROUND AND PURPOSE:The purpose of this study of pancreatic cancer patients treated with respiratory-guided stereotactic body radiotherapy (SBRT) on a standard linac was to investigate (a) the intrafractional relationship change (IRC) between a breathing signal and the tumor position, (b) the impact of IRC on the de...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12841
更新日期：2020-03-01 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.v15i4.4360
更新日期：2014-07-08 00:00:00
abstract：:Increasingly, the advent of multislice CT scanners, volume CT scanners, and total body spiral acquisition modes has led to the use of Multi Planar Reconstruction and 3D datasets. In considering 3D resolution properties of a CT system it is important to note that both the in-plane (x,y) and z-axis (slice thickness) inf...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i5.6294
更新日期：2016-09-08 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：2017-05-01 00:00:00
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journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12227
更新日期：2018-01-01 00:00:00
abstract：:The purpose of this study was to develop and evaluate filmless quality assurance (QA) tools for helical tomotherapy by using the signals from the on-board megavoltage computed tomography (MVCT) detector and applying a dedicated step-wedge phantom. The step-wedge phantom is a 15 cm long step-like aluminum block positio...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v13i1.3585
更新日期：2012-01-05 00:00:00
abstract：:The purpose of this study is to find the uncertainties in the reconstruction of MR compatible ring-tandem intracavitary applicators of high-dose rate image-based brachytherapy treatment planning using rigid registration of 3D MR and CT image fusion. Tandem and ring reconstruction in MR image based brachytherapy planni...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v15i2.4206
更新日期：2014-03-06 00:00:00
