Abstract：
:This paper investigates the accuracy of the two available calculation algorithms of the Oncentra MasterPlan three-dimensional treatment planning system (TPS)-- the pencil beam method and collapsed-cone convolution--in modeling the Varian enhanced dynamic wedge (EDW). Measurements were carried out for a dual high energy (6-15 MV) Varian DHX-S linear accelerator using ionization chambers for beam axis measurements (wedge factors and depth doses), film dosimetry for off-axis dose profiles measurements, and a diode matrix detector for two dimensional absolute dose distributions. Using both calculation algorithms, different configuration of symmetric and asymmetric fields varying the wedge's angle were tested. Accuracy of the treatment planning system was evaluated in terms of percentage differences between measured and calculated values for wedge factors, depth doses, and profiles. As far as the absolute dose distribution was concerned, the gamma index method (Low et al.) was used with 3% and 3 mm as acceptance criteria for dose difference and distance-to-agreement, respectively. Wedge factors and percentage depth doses were within 1% deviation between calculated and measured values. The comparison of measured and calculated dose profiles shows that the Van Dyk's acceptance criteria (Van Dyk et al.) are generally met; a disagreement can be noted for large wedge angles and field size limited to the low dose-low gradient region only. The 2D absolute dose distribution analysis confirms the good accuracy of the two calculation algorithms in modeling the enhanced dynamic wedge.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Pasquino M,Borca VC,Tofani S,Ozzello Fdoi
10.1120/jacmp.v10i2.2867subject
Has Abstractpub_date
2009-04-22 00:00:00pages
11-20issue
2issn
1526-9914journal_volume
10pub_type
杂志文章abstract：INTRODUCTION:This study aimed to investigate the feasibility of generating pseudo dual-energy CT (DECT) from one 120-kVp CT by using convolutional neural network (CNN) to derive additional information for quantitative image analysis through phantom study. METHODS:Dual-energy scans (80/140 kVp) and single-energy scans ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2020-10-14 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：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：2020-12-01 00:00:00
abstract：:The longitudinal coverage of a LINAC-mounted CBCT scan is limited to the corresponding dimensional limits of its flat panel detector, which is often shorter than the length of the treatment field. These limits become apparent when fields are designed to encompass wide regions, as when providing nodal coverage. Therefo...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2012-07-05 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.v4i2.2530
更新日期：2003-04-01 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：2016-09-08 00:00:00
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更新日期：2016-03-08 00:00:00
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更新日期：2015-11-08 00:00:00
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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：2003-01-01 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：2017-09-01 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：2019-12-01 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：2019-04-01 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：2012-09-06 00:00:00
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pub_type： 杂志文章
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更新日期：2016-01-08 00:00:00
abstract：:The purpose of this study is to simulate random and systematic RapidArc delivery errors for external beam prostate radiotherapy plans in order to determine the dose sensitivity for each error type. Ten prostate plans were created with a single 360° arc. The DICOM files for these treatment plans were then imported into...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v12i3.3409
更新日期：2011-05-20 00:00:00
abstract：:We conducted a metrological evaluation of the dosimetric impact due to the polysulfone cap used with the Fletcher-Williamson (FW) colpostat for 192Ir high-dose rate and pulsed-dose rate intracavitary brachytherapy using Monte Carlo simulations. Polysulfone caps with diameter of 30 mm, 25 mm, 20 mm, and 16 mm (mini-ovo...
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pub_type： 杂志文章
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更新日期：2010-01-28 00:00:00
abstract：PURPOSE:Previous studies suggest that within radiation oncology, medical physicists (MP) experience high workloads. Little is known about how MPs use social support (SS) in times of stress. METHODS:In collaboration with the Workgroup on Prevention of Medical Error, the American Association of Physicists in Medicine ad...
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pub_type： 杂志文章
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更新日期：2019-09-01 00:00:00
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更新日期：2016-11-08 00:00:00
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更新日期：2013-11-04 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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pub_type： 杂志文章
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更新日期：2017-05-01 00:00:00
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更新日期：2013-03-04 00:00:00
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journal_title：Journal of applied clinical medical physics
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更新日期：2015-07-08 00:00:00
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更新日期：2014-11-08 00:00:00
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更新日期：2013-03-04 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：2015-07-08 00:00:00
abstract：:The purpose of this study was to compare dosimetric parameters of treatment plans among four techniques for preoperative single-fraction partial breast radiotherapy in order to select an optimal treatment technique. The techniques evaluated were noncoplanar 3D conformal radiation therapy (3D CRT), noncoplanar intensit...
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更新日期：2015-01-08 00:00:00
