IIntroduction - MD Anderson Cancer Center



User Guide for Varian Medical Systems BrachyVisionTM Algorithm TestingDraft of 8th December 2015Contents TOC \o "1-3" \h \z \u IIntroduction PAGEREF _Toc437364751 \h 2IITest Case Import PAGEREF _Toc437364752 \h 4A. Accessing the Test Case Repository PAGEREF _Toc437364753 \h 4B. Downloading a Test Case PAGEREF _Toc437364754 \h 5C. Importing a Test Case into BrachyVision PAGEREF _Toc437364755 \h 6IIIDose Calculation PAGEREF _Toc437364756 \h 12TEST CASE 1 PAGEREF _Toc437364757 \h 12A.Confirming the Plan Properties PAGEREF _Toc437364758 \h 12B.Performing the ACUROS Dose Calculation PAGEREF _Toc437364759 \h 14TEST CASE 4 PAGEREF _Toc437364760 \h 17A.Inserting the Generic WG Applicator PAGEREF _Toc437364761 \h 17B.Confirming the Plan Properties PAGEREF _Toc437364762 \h 22C.Performing the ACUROS Dose Calculation PAGEREF _Toc437364763 \h 23IVDose Distribution Comparison PAGEREF _Toc437364764 \h parison Process Overview PAGEREF _Toc437364765 \h 25B.Doses at Specified Points PAGEREF _Toc437364766 \h 26C.2D Dose Maps and 1D Dose Profiles PAGEREF _Toc437364767 \h 27D.2D Dose Map Differences PAGEREF _Toc437364768 \h 28VTest Case Reporting PAGEREF _Toc437364769 \h 29VICreating a generic HDR Ir-192 virtual WG-MBDCA source model in the TPS PAGEREF _Toc437364770 \h 30VII References PAGEREF _Toc437364771 \h 31IIntroduction The American Association of Physicists in Medicine (AAPM) Task Group 186 reportADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "DOI" : "10.1118/1.4747264", "ISSN" : "0094-2405", "PMID" : "23039658", "abstract" : "The charge of Task Group 186 (TG-186) is to provide guidance for early adopters of model-based dose calculation algorithms (MBDCAs) for brachytherapy (BT) dose calculations to ensure practice uniformity. Contrary to external beam radiotherapy, heterogeneity correction algorithms have only recently been made available to the BT community. Yet, BT dose calculation accuracy is highly dependent on scatter conditions and photoelectric effect cross-sections relative to water. In specific situations, differences between the current water-based BT dose calculation formalism (TG-43) and MBDCAs can lead to differences in calculated doses exceeding a factor of 10. MBDCAs raise three major issues that are not addressed by current guidance documents: (1) MBDCA calculated doses are sensitive to the dose specification medium, resulting in energy-dependent differences between dose calculated to water in a homogeneous water geometry (TG-43), dose calculated to the local medium in the heterogeneous medium, and the intermediate scenario of dose calculated to a small volume of water in the heterogeneous medium. (2) MBDCA doses are sensitive to voxel-by-voxel interaction cross sections. Neither conventional single-energy CT nor ICRU\u2215ICRP tissue composition compilations provide useful guidance for the task of assigning interaction cross sections to each voxel. (3) Since each patient-source-applicator combination is unique, having reference data for each possible combination to benchmark MBDCAs is an impractical strategy. Hence, a new commissioning process is required. TG-186 addresses in detail the above issues through the literature review and provides explicit recommendations based on the current state of knowledge. TG-43-based dose prescription and dose calculation remain in effect, with MBDCA dose reporting performed in parallel when available. In using MBDCAs, it is recommended that the radiation transport should be performed in the heterogeneous medium and, at minimum, the dose to the local medium be reported along with the TG-43 calculated doses. Assignments of voxel-by-voxel cross sections represent a particular challenge. Electron density information is readily extracted from CT imaging, but cannot be used to distinguish between different materials having the same density. Therefore, a recommendation is made to use a number of standardized materials to maintain uniformity across institutions. Sensitivity analysis shows that this recommendation offers increased accur\u2026", "author" : [ { "dropping-particle" : "", "family" : "Beaulieu", "given" : "Luc", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Carlsson Tedgren", "given" : "Asa", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Carrier", "given" : "Jean-Francois", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Davis", "given" : "Stephen D", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Mourtada", "given" : "Firas", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Rivard", "given" : "Mark J", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Thomson", "given" : "Rowan M", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Verhaegen", "given" : "Frank", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Wareing", "given" : "Todd A", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Williamson", "given" : "Jeffrey F", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical physics", "id" : "ITEM-1", "issue" : "10", "issued" : { "date-parts" : [ [ "2012", "10" ] ] }, "page" : "6208-36", "title" : "Report of the Task Group 186 on model-based dose calculation methods in brachytherapy beyond the TG-43 formalism: current status and recommendations for clinical implementation.", "type" : "article-journal", "volume" : "39" }, "uris" : [ "" ] } ], "mendeley" : { "formattedCitation" : "¹", "plainTextFormattedCitation" : "1", "previouslyFormattedCitation" : "¹" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }1 provides general guidance for early adopters of model-based dose calculation algorithms (MBDCAs) for brachytherapy (BT) treatment planning. The report’s aim is to facilitate uniformity of clinical practice. Among its recommendations is a two-level approach to commissioning MBDCAs embedded in BT treatment planning systems (TPSs) insofar as specific tasks relating to the dose calculation algorithm are concerned. In commissioning level 1, the clinical physicist should assess agreement of MBDCA TPS-derived absolute dose or dose rate with the dose or dose rate obtained in the TPS using AAPM-recommended consensus TG-43 dosimetry parameters for a given BT source model. In commissioning level 2, the physicist should compare 3D dose distributions calculated with the MBDCA-based TPS for specific virtual phantoms mimicking clinical scenarios against benchmark dose distributions derived independently from the same phantom geometries.The AAPM Working Group on Dose Calculation Algorithms in Brachytherapy (WG-DCAB)ADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "author" : [ { "dropping-particle" : "", "family" : "", "given" : "", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "id" : "ITEM-1", "issued" : { "date-parts" : [ [ "0" ] ] }, "title" : "Working Group on Model-Based Dose Calculation Algorithms in Brachytherapy", "type" : "webpage" }, "uris" : [ "", "" ] } ], "mendeley" : { "formattedCitation" : "²", "plainTextFormattedCitation" : "2", "previouslyFormattedCitation" : "²" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }2 was created to facilitate implementation of the recommendations for MBDCA commissioning made in the TG-186 report. One of its charges is to develop a small number of prototypical virtual phantoms and corresponding benchmark dose distributions for use in level 1 and 2 commissioning of high dose rate (HDR) Ir-192 BT sources. These sources can be dealt with collectively by virtue of their similar photon emission properties, and therefore the WG-DCAB has designed a generic HDR Ir-192 virtual source for the express purpose of MBDCA commissioningADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "DOI" : "10.1118/1.4921020", "ISSN" : "0094-2405", "abstract" : "Purpose: In order to facilitate a smooth transition for brachytherapy dose calculations from the American Association of Physicists in Medicine (AAPM) Task Group No. 43 (TG-43) formalism to model-based dose calculation algorithms (MBDCAs), treatment planning systems (TPSs) using a MBDCA require a set of well-defined test case plans characterized by Monte Carlo (MC) methods. This also permits direct dose comparison to TG-43 reference data. Such test case plans should be made available for use in the software commissioning process performed by clinical end users. To this end, a hypothetical, generic high-dose rate (HDR) 192 Ir source and a virtual water phantom were designed, which can be imported into a TPS. Methods: A hypothetical, generic HDR 192 Ir source was designed based on commercially available sources as well as a virtual, cubic water phantom that can be imported into any TPS in DICOM format. The dose distribution of the generic 192 Ir source when placed at the center of the cubic phantom, and away from the center under altered scatter conditions, was evaluated using two commercial MBDCAs [Oncentra\u00ae Brachy with advanced collapsed-cone engine (ace) and BrachyVision acuros\u2122 ]. Dose comparisons were performed using state-of-the-art MC codes for radiation transport, including algebra , BrachyDose, geant4, mcnp5, mcnp6, and penelope2008. The methodologies adhered to recommendations in the AAPM TG-229 report on high-energy brachytherapy source dosimetry. TG-43 dosimetry parameters, an along-away dose-rate table, and primary and scatter separated (PSS) data were obtained. The virtual water phantom of (201)3 voxels (1 mm sides) was used to evaluate the calculated dose distributions. Two test case plans involving a single position of the generic HDR 192 Ir source in this phantom were prepared: (i) source centered in the phantom and (ii) source displaced 7 cm laterally from the center. Datasets were independently produced by different investigators. MC results were then compared against dose calculated using TG-43 and MBDCA methods. Results: TG-43 and PSS datasets were generated for the generic source, the PSS data for use with the ace algorithm. The dose-rate constant values obtained from seven MC simulations, performed independently using different codes, were in excellent agreement, yielding an average of 1.1109 \u00b1 0.0004 cGy/(h U) (k = 1, Type A uncertainty). MC calculated dose-rate distributions for the two plans were also found to be in excellent agr\u2026", "author" : [ { "dropping-particle" : "", "family" : "Ballester", "given" : "Facundo", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Carlsson Tedgren", "given" : "\u00c5sa", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Granero", "given" : "Domingo", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Haworth", "given" : "Annette", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Mourtada", "given" : "Firas", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Fonseca", "given" : "Gabriel Paiva", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Zourari", "given" : "Kyveli", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Papagiannis", "given" : "Panagiotis", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Rivard", "given" : "Mark J.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Siebert", "given" : "Frank-Andr\u00e9", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Sloboda", "given" : "Ron S.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Smith", "given" : "Ryan L.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Thomson", "given" : "Rowan M.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Verhaegen", "given" : "Frank", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Vijande", "given" : "Javier", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Ma", "given" : "Yunzhi", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Beaulieu", "given" : "Luc", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical Physics", "id" : "ITEM-1", "issue" : "6", "issued" : { "date-parts" : [ [ "2015", "6", "27" ] ] }, "page" : "3048-3062", "publisher" : "American Association of Physicists in Medicine", "title" : "A generic high-dose rate 192Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism", "type" : "article-journal", "volume" : "42" }, "uris" : [ "" ] } ], "mendeley" : { "formattedCitation" : "³", "plainTextFormattedCitation" : "3", "previouslyFormattedCitation" : "³" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }3. At the present time, the generic Ir-192 source model has been implemented by two MBDCA-based TPS vendors and hence is available to test the commissioning process described in the TG-186 report. Four treatment plans using virtual phantom geometries, designated Test Cases 1 - 4, have also been created by the WG for commissioning purposes and are described below.Test cases 1 - 4, which have been prepared by the WG-MBDCA, are based on a voxelized computational model of a homogeneous water cube (20.1 cm side) set inside either a water or an air cube (51.1 cm side), represented as a CT DICOM image series. Both cubes have a common center located at (x, y, z) = (0, 0, 0) cm and their sides are parallel. The dimensions, in-plane resolution, and number of images were chosen so that 511×511×511 cubic voxels (1 mm)3 fill the space. The patient coordinate system origin, as defined in the Image Position Patient (0020, 0032) and Image Orientation Patient (0020, 0037) DICOM tags, coincides with the cube centers which facilitates calculations and precludes comparison bias, i.e., the center voxel indices are (255, 255, 255) with the ordering [0:510]. An odd number of voxels was chosen so that the center of a voxel coincides with the geometrical center of the phantom. The four test cases are summarized in Table 1.Table 1: Test case geometries for ACUROS? algorithm testingTest CaseInner cube material‘Cube’Outer cube material‘BgBOX’Ir-192 source center locationIr-192 source orientationApplicator1H2OH2O(0, 0, 0) cm+znone2H2Oair(0, 0, 0) cm+znone3H2Oair(7, 0, 0) cm+znone4H2Oair(0, 0 ,0) cm+zGeneric WG ApplicatorThe geometry for Test Case 2 is depicted in the figure below as an example.xyThe geometry for Test Case 2 consists of a generic Ir-192 source located at coordinates (7, 0, 0) cm within a (20.1 cm)3 water-filled cube (‘Cube’, gray) embedded in a (50.1 cm)3 air-filled box (‘BgBOX’, black).The applicator in Test case 4, is also a generic, virtual shielded cylinder prepared by the WG-MBDCA for the purpose of MBDCA commissioning. Its basic features are illustrated in the following figure.(a)(b)PMMA shielded applicator (a) Dimensions and the origin of coordinates. (b) The black portion is a tungsten shield and the blue portion represents air.Varian? Medical Systems (Palo Alto, CA) has implemented the WG-MBDCA Ir-192 source and applicator in v.13 of their BrachyVision? (BV) planning system which incorporates the Acuros? algorithm. Acuros? is a grid-based Boltzmann transport equation solver developed by Transpire Inc. (Gig Harbor, WA) and optimized for use as a licensable module of BrachyVision versions 8.9 and higher, as well as external beam radiation therapy (Acuros XB in Eclipse). Information on the implementation of the ACUROS? algorithm for brachytherapy can be found in the reference guide available from the vendor.ADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "id" : "ITEM-1", "issued" : { "date-parts" : [ [ "0" ] ] }, "title" : "BrachyVision-Acuros algorithm reference guide (P/N B5202151R01A). Palo Alto, CA: Varian Medical Systems Inc.; 2009.", "type" : "report" }, "uris" : [ "", "" ] } ], "mendeley" : { "formattedCitation" : "⁴", "plainTextFormattedCitation" : "4", "previouslyFormattedCitation" : "⁴" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }4 Dosimetric benchmarking studies are also available in the literature.ADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "DOI" : "10.1118/1.3290630", "ISBN" : "0094-2405 (Print)\\r0094-2405 (Linking)", "ISSN" : "00942405", "PMID" : "20229874", "abstract" : "Purpose: The aim of this work is to validate a deterministic radiation transport based treatment planning system (TPS) for single 192Ir brachytherapy source dosimetry in homogeneous water geometries. Methods: TPS results were obtained using the deterministic radiation transport option of a BRACHYVISION v. 8.8 system for three characteristic source designs (VS2000, GMPlus HDR, and GMPlus PDR) with each source either centered in a 15 cm radius spherical water phantom, or positioned at varying distance away from the phantom center. Corresponding MC simulations were performed using the MCNPX code v.2.5.0 and source geometry models prepared using information provided by the manufacturers. Results: Comparison in terms of the AAPM TG-43 dosimetric formalism quantities, as well as dose rate distributions per unit air kerma strength with a spatial resolution of 0.1 cm, yielded close agreement between TPS and MC results for the sources centered in the phantom. Besides some regions close to the source longitudinal axes where discrepancies could be characterized as systematic, overall agreement for all three sources studied is comparable to the statistical (type A) uncertainty of MC simulations (1% at the majority of points in the geometry increasing to 2%-3% at points lying both away from the source center and close to the source longitudinal axis). A corresponding good agreement was also found between TPS and MC results for the sources positioned away from the phantom center. Conclusions: Results of this work attest the capability of the TPS to accurately account for the scatter conditions regardless of the size or shape of a given geometry of dosimetric interest, and the position of a source within it. This is important since, as shown in the literature and summarized also in this work, these factors could introduce a significant dosimetric effect that is currently ignored in clinical treatment planning. It is concluded that the implementation of the deterministic radiation transport option of the BRACHYVISION v. 8.8 system for 192 Ir brachytherapy dosimetry in homogeneous water geometries yields results of comparable accuracy to the golden standard of Monte Carlo simulation, in clinically viable calculation times. \u00a9 2010 American Association of Physicists in Medicine.", "author" : [ { "dropping-particle" : "", "family" : "Zourari", "given" : "K.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Pantelis", "given" : "E.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Moutsatsos", "given" : "A.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Petrokokkinos", "given" : "L.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Karaiskos", "given" : "P.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Sakelliou", "given" : "L.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Georgiou", "given" : "E.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Papagiannis", "given" : "P.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical Physics", "id" : "ITEM-1", "issue" : "2", "issued" : { "date-parts" : [ [ "2010" ] ] }, "page" : "649", "title" : "Dosimetric accuracy of a deterministic radiation transport based [sup 192]Ir brachytherapy treatment planning system. Part I: Single sources and bounded homogeneous geometries", "type" : "article-journal", "volume" : "37" }, "uris" : [ "" ] }, { "id" : "ITEM-2", "itemData" : { "DOI" : "10.1118/1.3567507", "ISSN" : "00942405", "abstract" : "Purpose: The aim of this work is the dosimetric validation of a deterministic radiation transport based treatment planning system (BRACHYVISION\u2122 v. 8.8, referred to as TPS in the following) for multiple 192Ir source dwell position brachytherapy applications employing a shielded applicator in homogeneous water geometries. Methods: TPS calculations for an irradiation plan employing seven VS2000 192Ir high dose rate (HDR) source dwell positions and a partially shielded applicator (GM11004380) were compared to corresponding Monte Carlo (MC) simulation results, as well as experimental results obtained using the VIP polymer gel-magnetic resonance imaging three-dimensional dosimetry method with a custom made phantom. Results: TPS and MC dose distributions were found in agreement which is mainly within \u00b12%. Considerable differences between TPS and MC results (greater than 2%) were observed at points in the penumbra of the shields (i.e., close to the edges of the \"shielded\" segment of the geometries). These differences were experimentally verified and therefore attributed to the TPS. Apart from these regions, experimental and TPS dose distributions were found in agreement within 2 mm distance to agreement and 5% dose difference criteria. As shown in this work, these results mark a significant improvement relative to dosimetry algorithms that disregard the presence of the shielded applicator since the use of the latter leads to dosimetry errors on the order of 20%-30% at the edge of the \"unshielded\" segment of the geometry and even 2%-6% at points corresponding to the potential location of the target volume in clinical applications using the applicator (points in the unshielded segment at short distances from the applicator). Conclusions: Results of this work attest the capability of the TPS to accurately account for the scatter conditions and the increased attenuation involved in HDR brachytherapy applications employing multiple source dwell positions and partially shielded applicators. \u00a9 2011 American Association of Physicists in Medicine.", "author" : [ { "dropping-particle" : "", "family" : "Petrokokkinos", "given" : "L.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Zourari", "given" : "K.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Pantelis", "given" : "E.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Moutsatsos", "given" : "A.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Karaiskos", "given" : "P.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Sakelliou", "given" : "L.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Seimenis", "given" : "I.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Georgiou", "given" : "E.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Papagiannis", "given" : "P.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical Physics", "id" : "ITEM-2", "issue" : "4", "issued" : { "date-parts" : [ [ "2011" ] ] }, "page" : "1981", "title" : "Dosimetric accuracy of a deterministic radiation transport based [sup 192]Ir brachytherapy treatment planning system. Part II: Monte Carlo and experimental verification of a multiple source dwell position plan employing a shielded applicator", "type" : "article-journal", "volume" : "38" }, "uris" : [ "" ] }, { "id" : "ITEM-3", "itemData" : { "DOI" : "10.1118/1.4770275", "ISSN" : "0094-2405", "PMID" : "23298082", "abstract" : "PURPOSE: To compare TG43-based and Acuros deterministic radiation transport-based calculations of the BrachyVision treatment planning system (TPS) with corresponding Monte Carlo (MC) simulation results in heterogeneous patient geometries, in order to validate Acuros and quantify the accuracy improvement it marks relative to TG43. METHODS: Dosimetric comparisons in the form of isodose lines, percentage dose difference maps, and dose volume histogram results were performed for two voxelized mathematical models resembling an esophageal and a breast brachytherapy patient, as well as an actual breast brachytherapy patient model. The mathematical models were converted to digital imaging and communications in medicine (DICOM) image series for input to the TPS. The MCNP5 v.1.40 general-purpose simulation code input files for each model were prepared using information derived from the corresponding DICOM RT exports from the TPS. RESULTS: Comparisons of MC and TG43 results in all models showed significant differences, as reported previously in the literature and expected from the inability of the TG43 based algorithm to account for heterogeneities and model specific scatter conditions. A close agreement was observed between MC and Acuros results in all models except for a limited number of points that lay in the penumbra of perfectly shaped structures in the esophageal model, or at distances very close to the catheters in all models. CONCLUSIONS: Acuros marks a significant dosimetry improvement relative to TG43. The assessment of the clinical significance of this accuracy improvement requires further work. Mathematical patient equivalent models and models prepared from actual patient CT series are useful complementary tools in the methodology outlined in this series of works for the benchmarking of any advanced dose calculation algorithm beyond TG43.", "author" : [ { "dropping-particle" : "", "family" : "Zourari", "given" : "K", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Pantelis", "given" : "E", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Moutsatsos", "given" : "A", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Sakelliou", "given" : "L", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Georgiou", "given" : "E", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Karaiskos", "given" : "P", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Papagiannis", "given" : "P", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical physics", "id" : "ITEM-3", "issue" : "1", "issued" : { "date-parts" : [ [ "2013", "1", "18" ] ] }, "page" : "011712", "publisher" : "American Association of Physicists in Medicine", "title" : "Dosimetric accuracy of a deterministic radiation transport based (192)Ir brachytherapy treatment planning system. Part III. Comparison to Monte Carlo simulation in voxelized anatomical computational models.", "type" : "article-journal", "volume" : "40" }, "uris" : [ "" ] }, { "id" : "ITEM-4", "itemData" : { "DOI" : "10.1118/1.3478278", "ISSN" : "00942405", "author" : [ { "dropping-particle" : "", "family" : "Mikell", "given" : "Justin K.", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Mourtada", "given" : "Firas", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical Physics", "id" : "ITEM-4", "issue" : "9", "issued" : { "date-parts" : [ [ "2010" ] ] }, "page" : "4733", "title" : "Dosimetric impact of an [sup 192]Ir brachytherapy source cable length modeled using a grid-based Boltzmann transport equation solver", "type" : "article-journal", "volume" : "37" }, "uris" : [ "" ] }, { "id" : "ITEM-5", "itemData" : { "DOI" : "10.1259/bjr.20140163", "ISSN" : "1748-880X", "PMID" : "25027247", "abstract" : "Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for (192)Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice.", "author" : [ { "dropping-particle" : "", "family" : "Papagiannis", "given" : "P", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Pantelis", "given" : "E", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Karaiskos", "given" : "P", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "The British journal of radiology", "id" : "ITEM-5", "issue" : "1041", "issued" : { "date-parts" : [ [ "2014", "9", "18" ] ] }, "language" : "EN", "page" : "20140163", "publisher" : "The British Institute of Radiology.", "title" : "Current state of the art brachytherapy treatment planning dosimetry algorithms.", "type" : "article-journal", "volume" : "87" }, "uris" : [ "" ] } ], "mendeley" : { "formattedCitation" : "^5\u20139", "plainTextFormattedCitation" : "5\u20139", "previouslyFormattedCitation" : "^5\u20139" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }5–9 The present guide has been prepared for experienced BrachyVision users participating in testing the TG-186 commissioning process for the ACUROS? algorithm and the WG-MBDCA HDR Ir-192 virtual source.In overview, the testing process involves downloading a Test Case treatment plan and an associated reference dose distribution and importing them into BV (Sec. II), locally calculating a dose distribution using Acuros (Sec. III), comparing the locally calculated and reference dose distributions (Sec. IV), and finally reporting the results of the dose comparison (Sec. V). As a “sanity check”, a second reference dose distribution generated by the WG-DCAB using the Acuros algorithm has been made available in the Test Case repository. Comparison of this latter reference dose distribution with the locally calculated one should not any yield dose differences.IITest Case Import A. Accessing the Test Case RepositoryData for test cases 1 - 4 will be made available via a web-accessible repository located at: For the internal (to the WG that is) testing, data are available in the WG dropbox folder as well as the pydio server WG members have access to. The main page contains links to Reference Data generated using the Monte Carlo code MCNP6, and to TPS-specific data for Elekta and Varian users.B. Downloading a Test CaseSelect a test case by navigating to the Varian Database folder and clicking on the Case of interest. This will open a download dialogue box. Save the associated .zip file to the BrachyVision workstation. Each test case .zip file contains 517 DICOM files including 511 virtual CT slices of a test phantom, a 3D reference radiotherapy dose (RD) matrix calculated using MCNP6 Monte Carlo simulation, a radiotherapy plan (RP), and a radiotherapy structure set (RS). The .zip file also includes a spreadsheet, DP_source_centered.xls (Test Cases 1 and 2) or DP_source_displaced.xls (Test Case 3), and an isodose line definition file, Test_case_isolines.xml. These latter files are provided to promote uniformity in dose reporting and comparison.Extract all files from the test case .zip folder to a local folder on the BrachyVision workstation.The contents of the zip folder will produce the following directory structure:\Case-1-ACUROS (Contains the CT data, Structure Sets, ACUROS plan and (pre-calculated) ACUROS dose grid)\ Case-1-MCNP6 (Contains the CT data, Structure Sets, MCNP6 plan and MCNP6 dose grid used as the primary reference)C. Importing a Test Case into BrachyVision Note: The following steps use Test Case 1 to illustrate the case import process. The same import process is used for all test cases. Click on the ‘File Import DICOM Media File Import Filter…’ button. The import of the test case will occur in two steps, firstly importing the pre-calculated ACUROS plan & dose and then importing the reference MCNP6 plan & dose.Click the button and browse to the folder containing the unzipped test case, ‘…\Case-1-ACUROS\’. Enter the folder and click .The system will display a list of CT Image data, RT Plan, RT Structure Set and RT Dose. Click the button and the button gets activated. Click the ‘Next>’ button and the system will read and validate the data ready for import. Then the ‘Log Details’ window appears with a message: “DVH import is not supported - histogram(s) will be skipped”. Click to continue. When the import window appears, select the button. The Patient Information will automatically populate the fields (as shown below).Click the button to create the new patient. The import window appears again with the WGMBDCA_1_II patient created. Click to import the new patient data.The plan opens when the import is complete. Click the ‘File Import DICOM Media File Import Filter…’ button again and select the folder containing the unzipped test case with the MCNP6 data files, ‘…\Case-1-MCNP6\’. Enter the folder and click . The system will display again a list of CT Image data, RT Plan, RT Structure Set and RT Dose.Click the button and the button gets activated. Click the ‘Next>’ button and the system will read and validate the data ready for import. The same ‘Log Details’ window appears with the message: “DVH import is not supported - histogram(s) will be skipped”. Click to continue. center1427205The system will attempt to match the patient details with an existing patient already in the BrachyVision database. Check the correct patient has been identified, in this case ID=’WGMBDCA_ 1_IIA’. If the system has not identified the correct patient, click the button and then the button to browse the database for the correct patient. Click to return to the ‘Import DICOM Media File Import Filter: Select Patient’ window.Click the button to start the import of the MCNP6 data.The plan opens when the import is complete with the two datasets loaded. The data for Test Case 1 have been imported. A local working copy of the ACUROS plan will now be created for the local user to calculate dose which will be then used for comparison with the reference MCNP6 dose.Select the ‘ACUROS’ plan, right-click on it and select the ‘Copy Plan’ option.Select the ‘ACUROS’ plan, right-click on it and select the ‘Paste Plan’ option. The ‘Plan Properties’ window opens. Enter ‘LocalUser’ in the ID field, ‘LocalUser’ in the Name field and Click . The import process and local plan creation is complete. Test Case 2, 3 and 4 can be imported into the BrachyVision system by following the same procedure above.IIIDose Calculation TEST CASE 1 Confirming the Plan Properties Select the ‘LocalUser’ plan, right-click on it and select ‘Drop to view’.Select the ‘Norm’ Reference Point, right-click on it and select ‘Properties’. Confirm the Reference Point ‘P1’ is at the “prescription” point (-1, 0, 0) with a prescription of 1 Gy. Select the ‘Applicator1, channel 1’, right-click on it and select ‘Properties’. Confirm all applicator properties as shown below. Click the button and confirm the applicator points (as shown below in the ‘Point Set Editor’ window) so that the applicator tip points towards the positive z-axis. Click to close all windows. A message appears saying ‘A change has occurred that invalidates the previous dose calculation. Real time dose is calculated according to TG-43 formalism’. Click . Click the ‘Window Dwell Control Window’ and confirm the active source dwell position is at the centre of the cube (130cm) and the dwell nominal time is 10sec.Select the ‘Dose’, right-click on it and select ‘Properties’. Confirm the ‘Dose Matrix Properties’ as shown below. Click . Performing the ACUROS Dose CalculationThe loaded ‘ACUROS LocalUser’ plan will have dose defined already as this is a copy from the downloaded data set but now is calculated according to TG-43 formalism (This dose will be overwritten by the local Acuros calculation).The end user will now perform a local model based dose calculation using the geometry defined by the selected case, overwriting any previous dose contained in the ‘ACUROS LocalUser’ plan.To perform an ACUROS dose calculation, click the button.1706245497205The ACUROS dose calculation window will appear. Confirm that for the calculation medium the ‘CT values’ are used and click button to begin the ACUROS calculation.757555299720The ‘Select Imaging Device’ window appears. Click . The calculation starts. When the calculation is completed, a warning message appears. Click . Close the window. The display will be updated with isodoses for the ACUROS calculation. The display will also specify the calculation algorithm ‘Transport in medium. Dose to water’.Click ‘Planning Isodose Levels’ to change the isodose line values and properly see the dose distribution. Click . Dose values exist inside the dose matrix defined. Click the button to see the dose matrix. Save the plan by clicking File Save All.The test case is ready for comparison as defined in section IV, Dose Distribution Comparison.Dose calculation in Test Cases 2 and 3 can be performed in the BrachyVision system by following the same procedure above. Note the different source center location in test case 3 (refer to Table 1).TEST CASE 4 Test Case 4 is different regarding the process that should be followed to perform the ACUROS dose calculation due to the presence of the solid Generic WG Applicator. Inserting the Generic WG Applicator When the import process and local plan creation is complete, the user can observe that the applicator channel containing the TG186 source is loaded but not the actual applicator probe. So before proceeding to the ACUROS dose calculation, the Generic WG applicator has to be inserted. Select the ‘LocalUser’ plan, right-click on it and select ‘Drop to view’.Select the ‘LocalUser – Transversal (axial)’ CT plane to activate it. With the ‘LocalUser – Transversal (axial)’ CT plane activated, click the ‘Insert’ tab and select the ‘Insert New Solid Applicator…’ option. The Solid Applicator library opens, select the ‘TG-186 Generic Shielded Applicator’, and add it to the plan by pressing the arrow pointing down and clicking . 5524500A message appears informing you that ‘A change has occurred that invalidates the previous dose calculation. Real time dose is calculated according to TG-43 formalism’. Click . 402526546355The WG Applicator is loaded with its central axis on the z-axis, the first available dwell position at the origin and the shielded part on the negative x-axis. Hence the applicator has to be rotated 180o (the shielding should be placed on the positive x-axis) and moved by 6.05 cm towards the positive z-axis so that the center of the active source dwell position of the plan moves at the origin. Maximize the ‘LocalUser – Transversal (axial)’ CT plane. Select the ‘TG186 Shielded’ applicator to have a better view of the part you have to rotate. Click the button. Place the mouse on the applicator and rotate it by 180o. 209169010160Return to the main view. Maximize the ‘LocalUser – Frontal (coronal)’ CT plane.Click the button to move the applicator 6.05 cm towards the positive z-axis. The center of the probe should be at the origin. 4267201905Return to the main view. Select the ‘TG186, channel 1’, right-click on it and select ‘Properties’.The ‘Applicator Properties’ window opens. Copy all the source position parameters to the ‘Applicator Properties’ of the ‘TG187, channel 2’ by selecting it from the list on the left. Note that when you switch between the applicator channels from the list on the left, the properties window also switches between the two obviating the need to close and re-open the properties window. Click the button and confirm that both applicators have the same points (as shown below in the ‘Point Set Editor’ window). In case the coordinates shown in your system do not match the values shown above, please repeat the procedure for correctly placing the applicator.Close all the above mentioned windows and return to the main view. Select the ‘TG186, channel 1’, right-click on it and select ‘Delete’.Click the ‘Window Dwell Control Window’ and confirm the active source dwell position is at the centre of the cube (124.30cm) and enter a dwell time t’=(Sknominal/Skcurrent)*50 sec. Sknominal = 40700 cGy*cm2/h. Confirming the Plan Properties Select the ‘Norm’ Reference Point, right-click on it and select ‘Properties’. Confirm the Reference Point ‘P1’ is at the “prescription” point (-2.3, 0, 0) with a prescription of 1 Gy. Select the ‘Dose’, right-click on it and select ‘Properties’. Confirm the ‘Dose Matrix Properties’ as shown below. Click . Performing the ACUROS Dose CalculationThe loaded ‘ACUROS LocalUser’ plan will have dose defined already as this is a copy from the downloaded data set but now it is calculated according to TG-43 formalism (This dose will be overwritten by the local Acuros calculation).The end user will now perform a local model based dose calculation using the geometry defined by the selected case, overwriting any previous dose contained in the ‘ACUROS LocalUser’ plan.To perform an ACUROS dose calculation, click the button.1706245497205The ACUROS dose calculation window will appear. Confirm that for the calculation medium the ‘CT values’ are used and click button to begin the ACUROS calculation.757555299720The ‘Select Imaging Device’ window appears. Click . The calculation starts. When the calculation is completed, a warnings message appears. Click . Close the window. The display will be updated with isodoses for the ACUROS calculation. The display will also specify the calculation algorithm ‘Transport in medium. Dose to water’.Click ‘Planning Isodose Levels’ to change the isodose line values and properly see the dose distribution. Click . Dose values exist inside the dose matrix defined. Click the button to see the dose matrix. Save the plan by clicking File Save All.The test case is ready for comparison as defined in section IV Dose Distribution Comparison.IVDose Distribution Comparison Comparison Process Overview Open the Plan Evaluation Link. 1699260-635Select the ‘LocalUser’ plan, right-click on it and select ‘Drop to view Left’.Select the ‘MCNP6_Case_4’ plan, right-click on it and select ‘Drop to view Right’.00The comparison of 3D dose distributions is typically done at specified points, in selected planes (dose maps), or for defined volumes within the distributions. Commonly used comparative metrics include dose differences, dose ratios, and the gamma index. The comparison tools available within the BV treatment planning system are limited to those based on dose differences; correspondingly, the detailed dose comparison and reporting guidance provided below is limited to dose differences.To augment the OCB dose comparison tools, end-users are encouraged to also make use of appropriate and available third party software, and to report their experiences using it. In this regard, public-domain software such as BrachyGuide v2ADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "ISSN" : "15269914", "abstract" : "This work presents BrachyGuide, a brachytherapy-dedicated software tool for the automatic preparation of input files for Monte Carlo simulation from treatment plans exported in DICOM RT format, and results of calculations performed for its benchmarking. Three plans were prepared using two computational models, the image series of a water sphere and a multicatheter breast brachytherapy patient, for each of two commercially available treatment planning systems: BrachyVision and Oncentra Brachy. One plan involved a single source dwell position of an 192Ir HDR source (VS2000 or mHDR-v2) at the center of the water sphere using the TG43 algorithm, and the other two corresponded to the TG43 and advanced dose calculation algorithm for the multicatheter breast brachytherapy patient. Monte Carlo input files were prepared using BrachyGuide and simulations were performed with MCNP v.6.1. For the TG43 patient plans, the Monte Carlo computational model was manually edited in the prepared input files to resemble TG43 dosimetry assumptions. Hence all DICOM RT dose exports were equivalent to corresponding simulation results and their comparison was used for benchmarking the use of BrachyGuide. Monte Carlo simulation results and corresponding DICOM RT dose exports agree within type A uncertainties in the majority of points in the computational models. Treatment planning system, algorithm, and source specific differences greater than type A uncertainties were also observed, but these were explained by treatment planning system-related issues and other sources of type B uncertainty. These differences have to be taken into account in commissioning procedures of brachytherapy dosimetry algorithms. BrachyGuide is accurate and effective for use in the preparation of commissioning tests for new brachytherapy dosimetry algorithms as a user-oriented commissioning tool and the expedition of retrospective patient cohort studies of dosimetry planning.", "author" : [ { "dropping-particle" : "", "family" : "Pantelis", "given" : "Evaggelos", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Peppa", "given" : "Vassiliki", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Lahanas", "given" : "Vasileios", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Pappas", "given" : "Eleftherios", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Papagiannis", "given" : "Panagiotis", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Journal of Applied Clinical Medical Physics", "id" : "ITEM-1", "issue" : "1", "issued" : { "date-parts" : [ [ "2015", "1", "8" ] ] }, "language" : "en", "page" : "208-218", "publisher" : "Journal of Applied Clinical Medical Physics", "title" : "BrachyGuide: A brachytherapy-dedicated DICOM RT viewer and interface to Monte Carlo simulation software", "type" : "article-journal", "volume" : "16" }, "uris" : [ "" ] } ], "mendeley" : { "formattedCitation" : "¹⁰", "plainTextFormattedCitation" : "10", "previouslyFormattedCitation" : "¹⁰" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }10 (available at: ) or SlicerRTADDIN CSL_CITATION { "citationItems" : [ { "id" : "ITEM-1", "itemData" : { "DOI" : "10.1118/1.4754659", "ISSN" : "0094-2405", "PMID" : "23039669", "abstract" : "PURPOSE: Interest in adaptive radiation therapy research is constantly growing, but software tools available for researchers are mostly either expensive, closed proprietary applications, or free open-source packages with limited scope, extensibility, reliability, or user support. To address these limitations, we propose SlicerRT, a customizable, free, and open-source radiation therapy research toolkit. SlicerRT aspires to be an open-source toolkit for RT research, providing fast computations, convenient workflows for researchers, and a general image-guided therapy infrastructure to assist clinical translation of experimental therapeutic approaches. It is a medium into which RT researchers can integrate their methods and algorithms, and conduct comparative testing.\n\nMETHODS: SlicerRT was implemented as an extension for the widely used 3D Slicer medical image visualization and analysis application platform. SlicerRT provides functionality specifically designed for radiation therapy research, in addition to the powerful tools that 3D Slicer offers for visualization, registration, segmentation, and data management. The feature set of SlicerRT was defined through consensus discussions with a large pool of RT researchers, including both radiation oncologists and medical physicists. The development processes used were similar to those of 3D Slicer to ensure software quality. Standardized mechanisms of 3D Slicer were applied for documentation, distribution, and user support. The testing and validation environment was configured to automatically launch a regression test upon each software change and to perform comparison with ground truth results provided by other RT applications.\n\nRESULTS: Modules have been created for importing and loading DICOM-RT data, computing and displaying dose volume histograms, creating accumulated dose volumes, comparing dose volumes, and visualizing isodose lines and surfaces. The effectiveness of using 3D Slicer with the proposed SlicerRT extension for radiation therapy research was demonstrated on multiple use cases.\n\nCONCLUSIONS: A new open-source software toolkit has been developed for radiation therapy research. SlicerRT can import treatment plans from various sources into 3D Slicer for visualization, analysis, comparison, and processing. The provided algorithms are extensively tested and they are accessible through a convenient graphical user interface as well as a flexible application programming interface.", "author" : [ { "dropping-particle" : "", "family" : "Pinter", "given" : "Csaba", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Lasso", "given" : "Andras", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Wang", "given" : "An", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Jaffray", "given" : "David", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" }, { "dropping-particle" : "", "family" : "Fichtinger", "given" : "Gabor", "non-dropping-particle" : "", "parse-names" : false, "suffix" : "" } ], "container-title" : "Medical physics", "id" : "ITEM-1", "issue" : "10", "issued" : { "date-parts" : [ [ "2012", "10" ] ] }, "page" : "6332-8", "title" : "SlicerRT: radiation therapy research toolkit for 3D Slicer.", "type" : "article-journal", "volume" : "39" }, "uris" : [ "" ] } ], "mendeley" : { "formattedCitation" : "¹¹", "plainTextFormattedCitation" : "11" }, "properties" : { "noteIndex" : 0 }, "schema" : "" }11 (available at: ) may be of interest.Doses at Specified Points To perform a dose point check in the BrachyVision:Click the ‘Point Dose’ button and place the mouse at the point of interest. Repeat the same procedure in both plans and check the dose value. 2740025405765Alternatively, create ‘New Reference Points’ in both plans at the same location and by selecting each point from the list on the left, review the calculated dose. Create a display grid using the grid definition tool in the toolbar. Click the button to facilitate the whole process. 0-19052D Dose Maps and 1D Dose Profiles To set up a side-by-side display of a locally calculated and a reference dose distribution:Choose or define an appropriate set of isolines for dose display by selecting ‘Planning Isodose Levels’ from the main menu. Click in the upper left panel of the display grid the / buttons, and zoom/pan the image to show an area of dosimetric interest. Click the button to create a dose profile for that area of the image. Use the cross-hair enabled to navigate through the Distance-Dose values of each plan. 1029335635Without closing the ‘Dose Line Profiler’ window, scroll through the slices to visually compare 2D doses and 1D dose profiles throughout the phantom.For the source centered geometry (Test Cases 1, 2 and 4), dose maps and “horizontal” dose profiles through the center of the source could be generated and recorded using screen capture software in planes x = 0 cm, y = 0 cm, and z = 0 cm. For the source displaced geometry (Test Case 3), dose maps and “horizontal” dose profiles through the center of the source could be created and recorded in planes x = 7 cm, y = 0 cm, and z = 0 cm.2D Dose Map Differences To display differences between a locally calculated and a reference dose distribution:Click the ‘Insert’ tab and select ‘New Plan Sum’. Tick both plans of interest for comparison by checking the box for each plan (‘LocalUser’ and ‘MCNP6_Case_’No’’). Set the ‘Operation’ for the reference plan to ‘–‘; this yields the difference in the locally calculated dose distribution relative to the reference distribution. Click Ok. Choose or define an appropriate set of isolines for dose display by selecting ‘Planning Isodose Levels’ from the main menu. 0441325Choose from the ‘Window’ tab the desired views. Click ‘Window Orthogonal Views and BEV’. Scroll through the slices to inspect 2D dose differences throughout the phantom.For the source centered geometry (Test Cases 1, 2 and 4), dose difference maps through the center of the source could be generated and recorded using screen capture software on planes x = 0 cm, y = 0 cm, and z = 0 cm. For the source displaced geometry (Test Case 3), dose difference maps through the center of the source could be created and recorded on planes x = 7 cm, y = 0 cm, and z = 0 cm.VTest Case Reporting Reporting on test case dose calculations is intended to provide: (1) end-user generated dosimetric data for inter-comparison purposes; and (2) feedback on the test case calculation process itself. Both types of information are valuable for refining the detailed testing procedures introduced in this Guide.Dosimetric data to be reported for each test case should include:Doses at selected points, in spreadsheet form (.xls, .xlsx)Dose maps and “horizontal” dose profiles in the planes indicated in Sec. IV.C, in screen capture form (.jpg, .tiff, .png)Dose difference maps in the planes indicated in Sec. IV.D, in screen capture form (.jpg, .tiff, .png)Any other dose data highlighting an issue that the end-user believes requires attention, in spreadsheet or screen capture form, along with a concise description of the issueWritten feedback on the calculation process itself should include:A description of any issues encountered with test case import, set up, dose calculation, dose display, etc.A description of any difficulties encountered in following this User GuideSuggestions for improving the calculation process and the User Guide.VICreating a generic HDR Ir-192 virtual WG-MBDCA source model in the TPSDepending on BV TPS version (v. 13 or higher) a source model for the generic WG source might have to be created before proceeding with test case import and dose calculations. Users should follow the BV reference guide instructions. In short, users can create a new radioactive source model with the ID “TG-186” in RT Administration. It is imperative that the above mentioned ID is used as it is used to link the source to the correct source model in the Acuros BV dose calculation algorithm. Since the source model is non-clinical, the status of the source model must be kept as “Commissioning” to ensure that it is not used in treatments. Users can then create a new brachytherapy treatment unit and add the new radioactive source model to the created treatment unit.VII ReferencesADDIN Mendeley Bibliography CSL_BIBLIOGRAPHY 1 L. Beaulieu et al., “Report of the Task Group 186 on model-based dose calculation methods in brachytherapy beyond the TG-43 formalism: current status and recommendations for clinical implementation.,” Med. Phys. 39(10), 6208–36 (2012).2 , Working Group on Model-Based Dose Calculation Algorithms in Brachytherapy, (n.d.).3 F. Ballester et al., “A generic high-dose rate 192Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism,” Med. Phys. 42(6), 3048–3062 (2015).4 BrachyVision-Acuros algorithm reference guide (P/N B5202151R01A). Palo Alto, CA: Varian Medical Systems Inc.; 2009. (n.d.).5 K. Zourari et al., “Dosimetric accuracy of a deterministic radiation transport based [sup 192]Ir brachytherapy treatment planning system. Part I: Single sources and bounded homogeneous geometries,” Med. Phys. 37(2), 649 (2010).6 L. Petrokokkinos et al., “Dosimetric accuracy of a deterministic radiation transport based [sup 192]Ir brachytherapy treatment planning system. Part II: Monte Carlo and experimental verification of a multiple source dwell position plan employing a shielded applicator,” Med. Phys. 38(4), 1981 (2011).7 K. Zourari et al., “Dosimetric accuracy of a deterministic radiation transport based (192)Ir brachytherapy treatment planning system. Part III. Comparison to Monte Carlo simulation in voxelized anatomical computational models.,” Med. Phys. 40(1), 011712 (2013).8 J.K. Mikell and F. Mourtada, “Dosimetric impact of an [sup 192]Ir brachytherapy source cable length modeled using a grid-based Boltzmann transport equation solver,” Med. Phys. 37(9), 4733 (2010).9 P. Papagiannis, E. Pantelis, and P. Karaiskos, “Current state of the art brachytherapy treatment planning dosimetry algorithms.,” Br. J. Radiol. 87(1041), 20140163 (2014).10 E. Pantelis, V. Peppa, V. Lahanas, E. Pappas, and P. Papagiannis, “BrachyGuide: A brachytherapy-dedicated DICOM RT viewer and interface to Monte Carlo simulation software,” J. Appl. Clin. Med. Phys. 16(1), 208–218 (2015).11 C. Pinter, A. Lasso, A. Wang, D. Jaffray, and G. Fichtinger, “SlicerRT: radiation therapy research toolkit for 3D Slicer.,” Med. Phys. 39(10), 6332–8 (2012). ................
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