Abstract：
:Detection and accurate quantification of treatment delivery errors is important in radiation therapy. This study aims to evaluate the accuracy of DVH based QA in quantifying delivery errors. Eighteen previously treated VMAT plans (prostate, H&N, and brain) were randomly chosen for this study. Conventional IMRT delivery QA was done with the ArcCHECK diode detector for error-free plans and plans with the following modifications: 1) induced monitor unit differences up to ± 3.0%, 2) control point deletion (3, 5, and 8 control points were deleted for each arc), and 3) gantry angle shift (2° uniform shift clockwise and counterclockwise). 2D and 3D distance-to-agreement (DTA) analyses were performed for all plans with SNC Patient software and 3DVH software, respectively. Subsequently, accuracy of the reconstructed DVH curves and DVH parameters in 3DVH software were analyzed for all selected cases using the plans in the Eclipse treatment planning system as standard. 3D DTA analysis for error-induced plans generally gave high pass rates, whereas the 2D evaluation seemed to be more sensitive to detecting delivery errors. The average differences for DVH parameters between each pair of Eclipse recalculation and 3DVH prediction were within 2% for all three types of error-induced treatment plans. This illustrates that 3DVH accurately quantifies delivery errors in terms of actual dose delivered to the patients. 2D DTA analysis should be routinely used for clinical evaluation. Any concerns or dose discrepancies should be further analyzed through DVH-based QA for clinically relevant results and confirmation of a conventional passing-rate-based QA.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Ma T,Podgorsak MB,Kumaraswamy LKdoi
10.1120/jacmp.v17i5.6344subject
Has Abstractpub_date
2016-09-08 00:00:00pages
273-282issue
5issn
1526-9914journal_volume
17pub_type
杂志文章abstract：:A thorax phantom was used to assess radiotherapy dose deviations induced by respiratory motion of the target volume. Both intensity modulated and static, non-modulated treatment plans were planned on CT scans of the phantom. The plans were optimized using various CT reconstructions, to investigate whether they had an ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12847
更新日期：2020-04-01 00:00:00
abstract：:The purpose of this study was to investigate amplitude gating combined with a coached breathing strategy for 10 MV flattening filter-free (FFF) volumetric-modulated arc therapy (VMAT) on the Varian TrueBeam linac. Ten patient plans for VMAT SABR liver were created using the Eclipse treatment planning system (TPS). The...
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：:Remote afterloading devices used for high-dose-rate (HDR) brachytherapy may be supplied with different sources, and these sources typically have differing initial source strengths. In addition, the proposed frequency for source changes may also vary, depending upon the source type. Dosimetric parameters unique to each...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v14i6.4239
更新日期：2013-11-04 00:00:00
abstract：:The main purposes of this study are to: 1) evaluate the accuracy of XiO treatment planning system (TPS) for different dose calculation grid size based on head phan-tom measurements in uniform scanning proton therapy (USPT); and 2) compare the dosimetric results for various dose calculation grid sizes based on real com...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i5.5510
更新日期：2015-09-08 00:00:00
abstract：:Modern three-dimensional image-guided intracavitary high dose rate (HDR) brachytherapy is often used in combination with external beam radiotherapy (EBRT) to manage cervical cancer. Intrafraction motion of critical organs relative to the HDR applicator in the time between the planning CT and treatment delivery can cau...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12462
更新日期：2018-11-01 00:00:00
abstract：:Radiographic film dosimetry provides fast, convenient 2-D dose distributions, but is challenged by the dependence of film response on scatter conditions (i.e., energy dependence). Verification of delivered dose in the surface buildup region is important for intensity modulated radiation therapy (IMRT) when volumes of ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v9i4.2782
更新日期：2008-10-24 00:00:00
abstract：PURPOSE:To provide insight into the types of questions asked to medical physicists by patients during one-on-one physicist-patient consults at one institution. MATERIALS AND METHODS:Medical physicists trained in patient communication techniques met with patients to provide an overview of the treatment planning and del...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12942
更新日期：2020-08-01 00:00:00
abstract：:In this study, we compared the amount of lung tissue irradiated when respiratory gating was imposed during expiration with the amount of lung tissue irradiated when gating was imposed during inspiration. Our hypothesis was that the amount of lung tissue spared increased as inspiration increased. Computed tomography (C...
journal_title：Journal of applied clinical medical physics
pub_type： 临床试验,杂志文章
doi：10.1120/jacmp.26.146
更新日期：2004-01-01 00:00:00
abstract：:Recently, specific computed tomography (CT) scanners have been equipped with organ-based tube current modulation (TCM) technology. It is possible that organ-based TCM will replace the conventional dose-reduction technique of reducing the effective milliampere-second. The aim of this study was to determine if organ-bas...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2012-03-08 00:00:00
abstract：:Hepatic encephalopathy (HE) is normally diagnosed by neuropsychological (NP) tests, which are not very specific and do not reveal the underlying pathology. Magnetic resonance imaging (MRI) and spectroscopy (MRS) of the brain offer alternative and possibly more specific markers for HE. These methods were applied in con...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v7i1.2151
更新日期：2006-01-01 00:00:00
abstract：:The goal of the present study was to develop a new dose-volume histogram (DVH)- based homogeneity index for effectively evaluating the dose homogeneity of intensity-modulated radiotherapy plans. The new index, called the sigma-index ("S-index") is defined as the standard deviation of the normalized differential DVH cu...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v8i2.2390
更新日期：2007-03-20 00:00:00
abstract：PURPOSE:To assess the impact of isocenter shifts due to linac gantry and table rotation during cranial stereotactic radiosurgery on D98 , target volume coverage (TVC), conformity (CI), and gradient index (GI). METHODS:Winston-Lutz (WL) checks were performed on two Elekta Synergy linacs. A stereotactic quality assuranc...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12854
更新日期：2020-05-01 00:00:00
abstract：:This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) dose distributions using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is present...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v15i4.4831
更新日期：2014-07-08 00:00:00
abstract：:The goal of this study was to investigate small field output factors (OFs) for flat-tening filter-free (FFF) beams on a dedicated stereotactic linear accelerator-based system. From this data, the collimator exchange effect was quantified, and detector-specific correction factors were generated. Output factors for 16 j...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i6.6433
更新日期：2016-11-08 00:00:00
abstract：:We investigate the role of adaptive radiation therapy in pediatric patients with diffuse pontine glioma and the impact of steroid-related weight gain on treatment parameters utilizing cone-beam CT. Fifteen patients with diffuse pontine glioma were treated with three-dimensional conformal radiation therapy and enrolled...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：
更新日期：2011-01-30 00:00:00
abstract：:A wide variety of existing combinations of target and filter materials (target/filter combinations) are used in mammography equipment. The patient dose depends on the X-ray quality that is derived from the target/filter combination, and a calibration of the dosimeter that is used in the measurement that corresponds to...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v16i6.5604
更新日期：2015-11-08 00:00:00
abstract：PURPOSE/OBJECTIVES:To present our linac-based SRS procedural technique for medically and/or surgically refractory trigeminal neuralgia (TN) treatment and simultaneously report our clinical outcomes. MATERIALS AND METHODS:Twenty-seven refractory TN patients who were treated with a single fraction of 80 Gy to TN. Treatm...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12057
更新日期：2017-03-01 00:00:00
abstract：:A Histogram Analysis in Radiation Therapy (HART) program was primarily developed to increase the efficiency and accuracy of dose-volume histogram (DVH) analysis of large quantities of patient data in radiation therapy research. The program was written in MATLAB to analyze patient plans exported from the treatment plan...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：
更新日期：2010-01-28 00:00:00
abstract：:Quality control (QC) of CT scanners is important to evaluate image quality and radiation dose. Different QC phantoms for testing image quality parameters on CT are commercially available, and Catphan phantoms are widely used for this purpose. More data from measured image quality parameters on CT are necessary to asse...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1002/acm2.12186
更新日期：2017-11-01 00:00:00
abstract：:TomoEDGE is an advanced delivery form of tomotherapy which uses a dynamic secondary collimator. This plan comparison study describes the new features, their clinical applicability, and their effect on plan quality and treatment speed. For the first 45 patients worldwide that were scheduled for a treatment with TomoEdg...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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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
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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
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更新日期：2020-09-01 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.v5i3.2026
更新日期：2004-07-01 00:00:00
abstract：:We report our technique for hemibody skin electron irradiation with a custom-made plywood shield. The technique is similar to our clinical total skin electron irradiation (TSEI), performed with a six-pair dual field (Stanford technique) at an extended source-to-skin distance (SSD) of 377 cm, with the addition of a ply...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i6.6367
更新日期：2016-11-08 00:00:00
abstract：:The control loop in the Varian DMLC system (V4.8) requires approximately 65 msec to monitor and halt the irradiation of a segment, causing an "overshoot" effect: the segment ends on a fractional monitor unit larger than that planned. As a result, the actual MU delivered may differ from that planned. In general, for st...
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：:Varian (Palo Alto, California, United States) recently released an online adaptation treatment platform, Ethos, which has introduced a new Dose Preview and Automated Plan Generation module despite sharing identical beam data with the existing Halcyon linac. The module incorporates a preconfigured beam model and the Ac...
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：:Measurement of cumulative dose ƒ(0,150) with a small ionization chamber within standard polymethyl methacrylate (PMMA) CT head and body phantoms, 150 mm in length, is a possible practical method for cone-beam computed tomography (CBCT) dosimetry. This differs from evaluating cumulative dose under scatter equilibrium c...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
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更新日期：2015-11-08 00:00:00
abstract：:A patient with a cardiac ventricular assist device (VAD) with computer-controlled driver presented to our department for radiation therapy. The treatment plan was 4500 cGy to the rectum over 25 fractions with 15MV photon beams. All beams avoided the pump and leads. The response to electromagnetic interference (EMI) wa...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v9i4.2851
更新日期：2008-10-29 00:00:00
abstract：:The purpose of the present study was to use a kilovoltage imaging device to measure interfractional and intrafractional setup deviations in patients with head-and-neck or brain cancers receiving intensity-modulated radiotherapy (IMRT) treatment. Before and after IMRT treatment, approximately 3 times weekly, 7 patients...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v8i4.2439
更新日期：2007-09-24 00:00:00
abstract：:The primary study objective was to assess radiation doses using a modified form of the Imaging Performance Assessment of Computed Tomography (CT) scanner (ImPACT) patient dosimetry for cardiac applications on an Aquilion ONE ViSION Edition scanner, including the Ca score, target computed tomography angiography (CTA), ...
journal_title：Journal of applied clinical medical physics
pub_type： 杂志文章
doi：10.1120/jacmp.v17i4.6218
更新日期：2016-07-08 00:00:00
