Abstract:
:The purpose of this study is to evaluate the accuracy of the electron Monte Carlo (eMC) dose calculation algorithm included in a commercial treatment planning system and compare its performance against an electron pencil beam algorithm. Several tests were performed to explore the system's behavior in simple geometries and in configurations encountered in clinical practice. The first series of tests were executed in a homogeneous water phantom, where experimental measurements and eMC-calculated dose distributions were compared for various combinations of energy and applicator. More specifically, we compared beam profiles and depth-dose curves at different source-to-surface distances (SSDs) and gantry angles, by using dose difference and distance to agreement. Also, we compared output factors, we studied the effects of algorithm input parameters, which are the random number generator seed, as well as the calculation grid size, and we performed a calculation time evaluation. Three different inhomogeneous solid phantoms were built, using high- and low-density materials inserts, to clinically simulate relevant heterogeneity conditions: a small air cylinder within a homogeneous phantom, a lung phantom, and a chest wall phantom. We also used an anthropomorphic phantom to perform comparison of eMC calculations to measurements. Finally, we proceeded with an evaluation of the eMC algorithm on a clinical case of nose cancer. In all mentioned cases, measurements, carried out by means of XV-2 films, radiographic films or EBT2 Gafchromic films. were used to compare eMC calculations with dose distributions obtained from an electron pencil beam algorithm. eMC calculations in the water phantom were accurate. Discrepancies for depth-dose curves and beam profiles were under 2.5% and 2 mm. Dose calculations with eMC for the small air cylinder and the lung phantom agreed within 2% and 4%, respectively. eMC calculations for the chest wall phantom and the anthropomorphic phantom also showed a positive agreement with the measurements. The retrospective dosimetric comparison of a clinical case, which presented scatter perturbations by air cavities, showed a difference in dose of up to 20% between pencil beam and eMC algorithms. When comparing to the pencil beam algorithm, eMC calculations are definitely more accurate at predicting large dose perturbations due to inhomogeneities.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Chamberland E,Beaulieu L,Lachance Bdoi
10.1120/jacmp.v16i3.4636subject
Has Abstractpub_date
2015-05-08 00:00:00pages
4636issue
3issn
1526-9914journal_volume
16pub_type
杂志文章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
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更新日期:2019-09-01 00:00:00
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更新日期:2020-10-15 00:00:00
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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:2021-01-10 00:00:00
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pub_type: 杂志文章
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更新日期:2000-04-01 00:00:00
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pub_type: 杂志文章
doi:10.1120/jacmp.v8i3.2377
更新日期:2007-07-17 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:2013-09-06 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:2014-01-06 00:00:00
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pub_type: 杂志文章
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更新日期:2016-07-08 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.v13i4.3613
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
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更新日期:2016-07-08 00:00:00
abstract:PURPOSE:Targeting and tracking of central lung tumors may be feasible on the Elekta MRI-linac (MRL) due to the soft-tissue visualization capabilities of MRI. The purpose of this work is to develop a novel treatment planning methodology to simulate tracking of central lung tumors with the MRL and to quantify the benefit...
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pub_type: 杂志文章
doi:10.1002/acm2.12233
更新日期:2018-01-01 00:00:00
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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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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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pub_type: 杂志文章
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更新日期:2010-04-19 00:00:00