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Almatani T. Investigation of variance reduction techniques on photon fluence and dose calculation efficiency for Elekta Agility head using EGSnrc MC code. JOURNAL OF TAIBAH UNIVERSITY FOR SCIENCE 2023. [DOI: 10.1080/16583655.2022.2160195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Yani S, Noviantoro YA, Husin AD, Rhani MF, Sumaryada T, Haryanto F. Verification of 3D-CRT dose distribution in ArcCheck phantom using Monte Carlo code. Radiat Phys Chem Oxf Engl 1993 2023; 210:111019. [DOI: 10.1016/j.radphyschem.2023.111019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Paschal HMP, Kabat CN, Papaconstadopoulos P, Kirby NA, Myers PA, Wagner TD, Stathakis S. Monte Carlo modeling of the Elekta Versa HD and patient dose calculation with EGSnrc/BEAMnrc. J Appl Clin Med Phys 2022; 23:e13715. [PMID: 35985698 PMCID: PMC9512349 DOI: 10.1002/acm2.13715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 04/18/2022] [Accepted: 06/12/2022] [Indexed: 11/10/2022] Open
Abstract
Introduction Numerous studies have proven the Monte Carlo method to be an accurate means of dose calculation. Although there are several commercial Monte Carlo treatment planning systems (TPSs), some clinics may not have access to these resources. We present a method for routine, independent patient dose calculations from treatment plans generated in a commercial TPS with our own Monte Carlo model using free, open‐source software. Materials and methods A model of the Elekta Versa HD linear accelerator was developed using the EGSnrc codes. A MATLAB script was created to take clinical patient plans and convert the DICOM RTP files into a format usable by EGSnrc. Ten patients’ treatment plans were exported from the Monaco TPS to be recalculated using EGSnrc. Treatment simulations were done in BEAMnrc, and doses were calculated using Source 21 in DOSXYZnrc. Results were compared to patient plans calculated in the Monaco TPS and evaluated in Verisoft with a gamma criterion of 3%/2 mm. Results Our Monte Carlo model was validated within 1%/1‐mm accuracy of measured percent depth doses and profiles. Gamma passing rates ranged from 82.1% to 99.8%, with 7 out of 10 plans having a gamma pass rate over 95%. Lung and prostate patients showed the best agreement with doses calculated in Monaco. All statistical uncertainties in DOSXYZnrc were less than 3.0%. Conclusion A Monte Carlo model for routine patient dose calculation was successfully developed and tested. This model allows users to directly recalculate DICOM RP files containing patients’ plans that have been exported from a commercial TPS.
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Affiliation(s)
- Holly M Parenica Paschal
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Christopher N Kabat
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | | | - Neil A Kirby
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Pamela A Myers
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Timothy D Wagner
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Sotirios Stathakis
- Department of Radiation Oncology, School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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Chand B, Singh R, Kumar M. Determination and validation of the initial beam parameters of Elekta Agility collimator head by Monte Carlo simulations. Phys Eng Sci Med 2022; 45:889-899. [PMID: 35849322 DOI: 10.1007/s13246-022-01159-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 07/01/2022] [Indexed: 11/24/2022]
Abstract
The availability of geometrical, physical, and initial beam parameters for Monte Carlo (MC) simulations of the Elekta Agility collimator head has become very difficult due to the proprietary nature of this data. This study presents strategies to independently determine the geometrical and physical properties of the components and initial beam parameters of the Agility collimator head for full beam simulations and postulates a benchmarking process using the EGSnrc MC toolkit. Target material of W (90%) and Re (10%) of 0.09 cm thickness, flattening filter of 1.77 cm thick stainless steel placed on 0.5 cm Al disc, and primary and secondary collimators of Tungsten alloy have been found to best fit the Agility head. The initial beam energy of 6.0 MeV with a radial distribution given as full-width half maxima (FWHM) of 0.301 cm (crossline) × 0.201 cm (inline) for 6 MV beam with a mean angular spread of 1.34° has been found best fitting the model. Variations of 0.29% and 0.59% have been noted in the measured and calculated values of TPR20,10 and D10 respectively. More than 90% dose points for all simulations passed the 2D gamma criteria of 3% DD, 3 mm DTA. This MC model of the Agility head can be used for dose calculation and validation of advanced treatment techniques.
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Affiliation(s)
- Bhagat Chand
- Department of Physics, Lovely Professional University, Phagwara, 1444141, Punjab, India.,Department of Radiotherapy, Dr. Rajendra Prasad Government Medical College, Tanda, Kangra, 176001, Himachal Pradesh, India
| | - Ranjit Singh
- Department of Radiotherapy, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Mukesh Kumar
- Department of Physics, Lovely Professional University, Phagwara, 1444141, Punjab, India.
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Chuah K, Abdul Aziz M, Jayamani J. Determination of the Small-Field Output Factor for 6 MV Photon Beam Using EGSnrc Monte Carlo. J Med Phys 2022; 47:301-308. [PMID: 36684700 PMCID: PMC9846995 DOI: 10.4103/jmp.jmp_40_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/04/2022] [Accepted: 07/20/2022] [Indexed: 11/10/2022] Open
Abstract
Accuracy of ionization chamber (IC) to measure the scatter output factor (Scp) of a linear accelerator (linac) is crucial, especially in small field (<4 cm × 4 cm). The common IC volume of 0.6 cc is not adequate for small-field measurement and not all radiotherapy centers can afford to purchase additional IC due to the additional cost. This study aimed to determine the efficiency of the EGSnrc Monte Carlo (MC) to calculate the Scp for various field sizes including small field in Elekta Synergy (Agility multileaf collimator) linac. The BEAMnrc and DOSXYZnrc user codes were used to simulate a 6 MV linac model for various field sizes and calculate the radiation dose output in water phantom. The modeled linac treatment head was validated by comparing the percentage depth dose (PDD), beam profile, and beam quality (Tissue Phantom Ratio (TPR)20,10) with the IC measurement. The validated linac model was simulated to calculate the Scp consisting of collimator scatter factor (Sc) and phantom scatter factor (Sp). The PDD and beam profile of the simulated field sizes were within a good agreement of ±2% compared with the measured data. The TPR20,10 value was 0.675 for field size 10 cm × 10 cm. The Scp, Sc, and Sp simulated values were close to the IC measurement within ±2% difference. The simulation for Sc and Sp in 3 cm × 3 cm field size was calculated to be 0.955 and 0.884, respectively. In conclusion, this study validated the efficiency of the MC simulation as a promising tool for the Scp calculation including small-field size for linac.
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Affiliation(s)
- K.W. Chuah
- Medical Radiation Programme, School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
| | - M.Z. Abdul Aziz
- Department of Biomedical Imaging, Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Kepala Batas, Pulau Pinang, Malaysia
| | - J Jayamani
- Medical Radiation Programme, School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia
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Using a fixed-jaw technique to achieve superior delivery accuracy and plan quality in single-isocenter multiple-target stereotactic radiosurgery for brain metastases. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2022. [DOI: 10.1016/j.jrras.2022.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Almatani T, Hugtenburg RP, Smakovs A. A Monte Carlo model of an agility head for a 10-MV photon beam. JOURNAL OF TAIBAH UNIVERSITY FOR SCIENCE 2022. [DOI: 10.1080/16583655.2022.2050097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | - Richard P. Hugtenburg
- College of Medicine, Swansea University, Swansea, UK
- Department of Medical Physics and Clinical Engineering, Swansea Bay University Health Board, Swansea, UK
| | - Artjoms Smakovs
- Department of Medical Physics and Clinical Engineering, Swansea Bay University Health Board, Swansea, UK
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Yano M, Araki F, Ohno T. Monte Carlo study of small-field dosimetry for an ELEKTA Unity MR-Linac system. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Yang HJ, Kim TH, Schaarschmidt T, Park DW, Kang SH, Chung HT, Suh TS. A multivariate approach to determine electron beam parameters for a Monte Carlo 6 MV Linac model: Statistical and machine learning methods. Phys Med 2021; 93:38-45. [PMID: 34920381 DOI: 10.1016/j.ejmp.2021.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 11/28/2021] [Accepted: 12/07/2021] [Indexed: 11/28/2022] Open
Abstract
PURPOSE This study aimed to determine the optimal initial electron beam parameters of a Linac for radiotherapy with a multivariate approach using statistical and machine-learning tools. METHODS For MC beam commissioning, a 6 MV Varian Clinac was simulated using the Geant4 toolkit. The authors investigated the relations between simulated dose distribution and initial electron beam parameters, namely, mean energy (E), energy spread (ES), and radial beam size (RS). The goodness of simulation was evaluated by the slope of differences between the simulated and the golden beam data. The best-fit combination of the electron beam parameters that minimized the slope of dose difference was searched through multivariate methods using conventional statistical methods and machine-learning tools of the scikit-learn library. RESULTS Simulation results with 87 combinations of the electron beam parameters were analyzed. Regardless of being univariate or multivariate, traditional statistical models did not recommend a single parameter set simultaneously minimizing slope of dose differences for percent depth dose (PDD) and lateral dose profile (LDP). Two machine learning classification modules, RandomForestClassifier and BaggingClassifier, agreed in recommending (E = 6.3 MeV, ES = ±5.0%, RS = 1.0 mm) for predicting simultaneous acceptance of PDD and LDP. CONCLUSIONS The machine learning with random-forest and bagging classifier modules recommended a consistent result. It was possible to draw an optimal electron beam parameter set using multivariate methods for MC simulation of a radiotherapy 6 MV Linac.
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Affiliation(s)
- Hye Jeong Yang
- Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Tae Hoon Kim
- Department of Nuclear Engineering, Hanyang University College of Engineering, Seoul, Republic of Korea
| | - Thomas Schaarschmidt
- Department of Nuclear Engineering, Hanyang University College of Engineering, Seoul, Republic of Korea
| | - Dong-Wook Park
- Department of Radiation Oncology, Ilsan Paik Hospital, Goyang, Republic of Korea
| | - Seung Hee Kang
- Department of Radiation Oncology, Ilsan Paik Hospital, Goyang, Republic of Korea
| | - Hyun-Tai Chung
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Republic of Korea.
| | - Tae Suk Suh
- Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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Thi Oanh L, Thanh Tai D, Thi Hong Loan T, Chow JCL. Calculation of Jaws-only IMRT (JO-IMRT) dose distributions based on the AAPM TG-119 test cases using Monte Carlo simulation and Prowess Panther treatment planning system. NUCLEAR ENGINEERING AND TECHNOLOGY 2021. [DOI: 10.1016/j.net.2021.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Kandlakunta P, Momin S, Sloop A, Zhang T, Khan R. Characterizing a Geant4 Monte Carlo model of a multileaf collimator for a TrueBeam™ linear accelerator. Phys Med 2019; 59:1-12. [PMID: 30928056 DOI: 10.1016/j.ejmp.2019.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/11/2019] [Accepted: 02/12/2019] [Indexed: 11/26/2022] Open
Abstract
PURPOSE The purpose of this work was to develop and validate a multileaf collimator (MLC) model for a TrueBeam™ linac using Geant4 Monte Carlo (MC) simulation kit. METHODS A Geant4 application was developed to accurately represent TrueBeam™ linac. Pre-computed phase-space file in a plane just above the jaws was used for radiation transport. A Varian 120 leaf Millennium™ MLC was modeled using geometry and material specifications provided by the manufacturer using Geant4 constructs. Leaf characteristics e.g. tongue-groove design, variable thickness, interleaf gap were simulated. The linac model was validated by comparing simulated dose profiles and depth-doses with experimental data using an ionization chamber in water. Dosimetric characteristics of the MLC such as inter- and intra-leaf leakage, penumbra effect, MLC leaf positioning, and dynamic characteristics were also investigated. RESULTS For the depth dose curves, 99% of the calculated data points agree within 1% of the experimental values for the 4 × 4 cm2 and 10 × 10 cm2 and within 2% of the experimental values for 20 × 20, 30 × 30 and 40 × 40 cm2 jaw defined fields. The cross-plane dose profiles show agreement <2% for depths up to 10 cm and to within 4% beyond 10 cm. MLC dosimetric characterization with MC agree well with film measurements. The rounded leaf penumbra remained constant throughout the range of leaf motion. CONCLUSIONS The TrueBeam™ linac equipped with 120-leaf MLC was successfully modeled using Geant4. The accuracy of the model was verified by comparing the simulations with experiments. The model may be utilized for independent dose verification and QA of IMRT.
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Affiliation(s)
- Praneeth Kandlakunta
- Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St Louis, MO, USA
| | - Shadab Momin
- Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St Louis, MO, USA
| | - Austin Sloop
- Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St Louis, MO, USA
| | - Tiezhi Zhang
- Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St Louis, MO, USA
| | - Rao Khan
- Department of Radiation Oncology, Washington University in St. Louis School of Medicine, St Louis, MO, USA.
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Chen J, Morin O, Weethee B, Perez-Andujar A, Phillips J, Held M, Kearney V, Han DY, Cheung J, Chuang C, Valdes G, Sudhyadhom A, Solberg T. Optimizing beam models for dosimetric accuracy over a wide range of treatments. Phys Med 2019; 58:47-53. [PMID: 30824149 DOI: 10.1016/j.ejmp.2019.01.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 01/12/2019] [Accepted: 01/16/2019] [Indexed: 11/29/2022] Open
Abstract
This work presents a systematic approach for testing a dose calculation algorithm over a variety of conditions designed to span the possible range of clinical treatment plans. Using this method, a TrueBeam STx machine with high definition multi-leaf collimators (MLCs) was commissioned in the RayStation treatment planning system (TPS). The initial model parameters values were determined by comparing TPS calculations with standard measured depth dose and profile curves. The MLC leaf offset calibration was determined by comparing measured and calculated field edges utilizing a wide range of MLC retracted and over-travel positions. The radial fluence was adjusted using profiles through both the center and corners of the largest field size, and through measurements of small fields that were located at highly off-axis positions. The flattening filter source was adjusted to improve the TPS agreement for the output of MLC-defined fields with much larger jaw openings. The MLC leaf transmission and leaf end parameters were adjusted to optimize the TPS agreement for highly modulated intensity-modulated radiotherapy (IMRT) plans. The final model was validated for simple open fields, multiple field configurations, the TG 119 C-shape target test, and a battery of clinical IMRT and volumetric-modulated arc therapy (VMAT) plans. The commissioning process detected potential dosimetric errors of over 10% and resulted in a final model that provided in general 3% dosimetric accuracy. This study demonstrates the importance of using a variety of conditions to adjust a beam model and provides an effective framework for achieving high dosimetric accuracy.
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Affiliation(s)
- Josephine Chen
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States.
| | - Olivier Morin
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Brandon Weethee
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Angelica Perez-Andujar
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Justin Phillips
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Mareike Held
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Vasant Kearney
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Dae Yup Han
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Joey Cheung
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Cynthia Chuang
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Gilmer Valdes
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Atchar Sudhyadhom
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
| | - Timothy Solberg
- Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, Suite H1031, San Francisco, CA 94115, United States
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Saenz DL, Li Y, Rasmussen K, Stathakis S, Pappas E, Papanikolaou N. Dosimetric and localization accuracy of Elekta high definition dynamic radiosurgery. Phys Med 2018; 54:146-151. [PMID: 30337004 DOI: 10.1016/j.ejmp.2018.10.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 08/24/2018] [Accepted: 10/02/2018] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND AND PURPOSE With the increasingly prominent role of stereotactic radiosurgery in radiation therapy, there is a clinical need for robust, efficient, and accurate solutions for targeting multiple sites with one patient setup. The end-to-end accuracy of high definition dynamic radiosurgery with Elekta treatment planning and delivery systems was investigated in this study. MATERIALS AND METHODS A patient-derived CT scan was used to create a radiosurgery plan to seven targets in the brain. Monaco was used for treatment planning using 5 VMAT non-coplanar arcs. Prior to delivery, 3D-printed phantoms from RTsafe were ordered including a gel phantom for 3D dosimetry, phantom with 2D film insert, and an ion chamber phantom for point dose measurement. Delivery was performed using the Elekta VersaHD, XVI cone-beam CT, and HexaPOD six degree of freedom tabletop. RESULTS Absolute dose accuracy was verified within 2%. 3D global gamma analysis in the film measurement revealed 3%/2 mm passing rates >95%. Gel dosimetry 3D global gamma analysis (3%/2 mm) were above 90% for all targets with the exception of one. Results were indicative of typical end-to-end accuracies (<1 mm spatial uncertainty, 2% dose accuracy) within 4 cm of isocenter. Beyond 4 cm, 2 mm accuracy was found. CONCLUSIONS High definition dynamic radiosurgery expands clinically acceptable stereotactic accuracy to a sphere around isocenter allowing for radiosurgery of several targets with one setup with a high degree of dosimetric precision. Gel dosimetry proved to be an essential tool for the validation of the 3D dose distributions in this technique.
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Affiliation(s)
- Daniel L Saenz
- University of Texas Health San Antonio, Department of Radiation Oncology, 7979 Wurzbach Road, San Antonio, TX 78229, United States.
| | - Ying Li
- University of Texas Health San Antonio, Department of Radiation Oncology, 7979 Wurzbach Road, San Antonio, TX 78229, United States
| | - Karl Rasmussen
- University of Texas Health San Antonio, Department of Radiation Oncology, 7979 Wurzbach Road, San Antonio, TX 78229, United States
| | - Sotirios Stathakis
- University of Texas Health San Antonio, Department of Radiation Oncology, 7979 Wurzbach Road, San Antonio, TX 78229, United States
| | - Evangelos Pappas
- University of West Attica, Department of Biomedical Sciences, Radiology & Radiotherapy Sector, Athens, Greece
| | - Niko Papanikolaou
- University of Texas Health San Antonio, Department of Radiation Oncology, 7979 Wurzbach Road, San Antonio, TX 78229, United States
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