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Simiele E, Romero IO, Wang JY, Chen Y, Lozko Y, Severyn Y, Skinner L, Yang Y, Xing L, Gibbs I, Hiniker SM, Kovalchuk N. Automated contouring, treatment planning, and quality assurance for VMAT craniospinal irradiation (VMAT-CSI). Front Oncol 2024; 14:1378449. [PMID: 38660134 PMCID: PMC11039907 DOI: 10.3389/fonc.2024.1378449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/18/2024] [Indexed: 04/26/2024] Open
Abstract
Purpose Create a comprehensive automated solution for pediatric and adult VMAT-CSI including contouring, planning, and plan check to reduce planning time and improve plan quality. Methods Seventy-seven previously treated CSI patients (age, 2-67 years) were used for creation of an auto-contouring model to segment 25 organs at risk (OARs). The auto-contoured OARs were evaluated using the Dice Similarity Coefficient (DSC), 95% Hausdorff Distance (HD95), and a qualitative ranking by one physician and one physicist (scale: 1-acceptable, 2-minor edits, 3-major edits). The auto-planning script was developed using the Varian Eclipse Scripting API and tested with 20 patients previously treated with either low-dose VMAT-CSI (12 Gy) or high-dose VMAT-CSI (36 Gy + 18 Gy boost). Clinically relevant metrics, planning time, and blinded physician review were used to evaluate significance of differences between the auto and manual plans. Finally, the plan preparation for treatment and plan check processes were automated to improve efficiency and safety of VMAT-CSI. Results The auto-contours achieved an average DSC of 0.71 ± 0.15, HD95 of 4.81 ± 4.68, and reviewers' ranking of 1.22 ± 0.39, indicating close to "acceptable-as-is" contours. Compared to the manual CSI plans, the auto-plans for both dose regimens achieved statistically significant reductions in body V50% and Dmean for parotids, submandibular, and thyroid glands. The variance in the dosimetric parameters decreased for the auto-plans as compared to the manual plans indicating better plan consistency. From the blinded review, the auto-plans were marked as equivalent or superior to the manual-plans 88.3% of the time. The required time for the auto-contouring and planning was consistently between 1-2 hours compared to an estimated 5-6 hours for manual contouring and planning. Conclusions Reductions in contouring and planning time without sacrificing plan quality were obtained using the developed auto-planning process. The auto-planning scripts and documentation will be made freely available to other institutions and clinics.
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Melton MK, Stanley DN, Iqbal Z, Keene KS, Simiele E, McDonald A. Acute Toxicity of Total Body Irradiation Using Volumetric Arc Therapy With a Focus on the Effect of Lung Dose Rate. Adv Radiat Oncol 2024; 9:101430. [PMID: 38406392 PMCID: PMC10882112 DOI: 10.1016/j.adro.2023.101430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 11/27/2023] [Indexed: 02/27/2024] Open
Abstract
Purpose To report adverse effects of high dose total body irradiation (TBI) delivered using a volumetric arc therapy (VMAT) technique and to assess pulmonary toxicity at dose rates of 40 and 100 monitor units per minute (MU/min). Methods and Materials This retrospective study included patients >18 years old who received ≥8 Gy TBI using a VMAT technique. The TBI dose was prescribed to a planning target volume consisting of a 0.5 cm retraction of the body with the lungs subtracted. The objective function specified planning target volume coverage goals of D100% ≥ 90% and Dmax <130%. A lung dose control structure consisting of a 1 cm retraction of the lung volume was limited to Dmean <75%. Treatments were initially delivered with a dose rate of 40 MU/min for the thoracic isocenters and 100 MU/min for the other isocenters. Beginning in January 2021, a dose rate of 100 MU/min was used for all isocenters. All treatments were administered in 2 Gy fractions delivered twice daily. Acute toxicity was assessed for 30 days after TBI. Results A total of 29 patients were included in this analysis who received TBI between January 2019 and October 2021. Prescription dose ranged from 8 to 12 Gy. Mean lung dose was 7.9 Gy (SD, 1.4 Gy) for patients treated at 40 MU/min and for patients treated at 100 MU/min 7.1 Gy (SD, 1.3 Gy). Mucositis was the most common grade 3 toxicity and occurred in 10 (34%) patients. Only 1 instance of pneumonitis was observed and occurred in a patient who received a mean lung dose of 10.1 Gy delivered at 40 MU/min. Conclusions In this cohort of patients who received high dose TBI using a VMAT technique, the composite rate of acute toxicity was not unexpectedly high. We did not observe an increase in lung toxicity after increasing the dose rate of the thoracic isocenters from 40 MU/min to 100 MU/min.
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Affiliation(s)
- Michael Kole Melton
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Dennis N. Stanley
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Zohaib Iqbal
- Department of Radiation Oncology, The University of Texas Southwestern, Dallas, Texas
| | - Kimberly S. Keene
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Eric Simiele
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Andrew McDonald
- Department of Radiation Oncology, The University of Alabama at Birmingham, Birmingham, Alabama
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Shi M, Simiele E, Han B, Pham D, Palomares P, Aguirre M, Gensheimer M, Vitzthum L, Le QT, Surucu M, Kovalchuk N. First-Year Experience of Stereotactic Body Radiation Therapy/Intensity Modulated Radiation Therapy Treatment Using a Novel Biology-Guided Radiation Therapy Machine. Adv Radiat Oncol 2024; 9:101300. [PMID: 38260216 PMCID: PMC10801639 DOI: 10.1016/j.adro.2023.101300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/16/2023] [Indexed: 01/24/2024] Open
Abstract
Purpose The aim of this study was to present the first-year experience of treating patients using intensity modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) with a biology-guided radiation therapy machine, the RefleXion X1 system, installed in a clinical setting. Methods and Materials A total of 78 patients were treated on the X1 system using IMRT and SBRT from May 2021 to May 2022. Clinical and technical data including treatment sites, number of pretreatment kilovoltage computed tomography (kVCT) scans, beam-on time, patient setup time, and imaging time were collected and analyzed. Machine quality assurance (QA) results, machine performance, and user satisfactory survey were also collected and reported. Results The most commonly treated site was the head and neck (63%), followed by the pelvis (23%), abdomen (8%), and thorax (6%). Except for 5 patients (6%) who received SBRT treatments for bony metastases in the pelvis, all treatments were conventionally fractionated IMRT. The number of kVCT scans per fraction was 1.2 ± 0.5 (mean ± standard deviation). The beam-on time was 9.2 ± 3.5 minutes. The patient setup time and imaging time per kVCT was 4.8 ± 2.6 minutes and 4.6 ± 1.5 minutes, respectively. The daily machine output deviation was 0.4 ± 1.2% from the baseline. The patient QA had a passing rate of 97.4 ± 2.8% at 3%/2 mm gamma criteria. The machine uptime was 92% of the total treatment time. The daily QA and kVCT image quality received the highest level of satisfaction. The treatment workflow for therapists received the lowest level of satisfaction. Conclusions One year after the installation, 78 patients were successfully treated with the X1 system using IMRT and/or SBRT. With the recent Food and Drug Administration clearance of biology-guided radiation therapy, our department is preparing to treat patients using positron emission tomography-guidance via a new product release, which will address deficiencies in the current image-guided radiation therapy workflow.
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Affiliation(s)
- Mengying Shi
- Department of Radiation Oncology, Stanford University, Stanford, California
- Department of Radiation Oncology, University of California, Irvine, Orange, California
| | - Eric Simiele
- Department of Radiation Oncology, Stanford University, Stanford, California
- Department of Radiation Oncology, University of Alabama, Birmingham, Alabama
| | - Bin Han
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Daniel Pham
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Paul Palomares
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Michaela Aguirre
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Michael Gensheimer
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Lucas Vitzthum
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Quynh-Thu Le
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Nataliya Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California
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Ngo N, Blomain ES, Simiele E, Romero I, Hoppe RT, Hiniker SM, Kovalchuk N. Improved organ sparing using auto-planned Stanford volumetric modulated arc therapy for total body irradiation technique. Pediatr Blood Cancer 2023; 70:e30589. [PMID: 37486149 DOI: 10.1002/pbc.30589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/07/2023] [Accepted: 07/08/2023] [Indexed: 07/25/2023]
Abstract
PURPOSE/OBJECTIVES To evaluate dosimetric differences between auto-planned volumetric modulated arc therapy (VMAT) total body irradiation (TBI) technique and two-dimensional radiotherapy using anterior-posterial/posterio-anterial beams (2D AP/PA) TBI technique. METHODS Ten pediatric patients treated with VMAT-TBI on Varian c-arm linac were included in this study. VMAT-TBI plans were generated using our in-house developed and publicly shared auto-planning scripts. For each VMAT-TBI plan, a 2D AP/PA plan was created replicating the institution's clinical setup with the patient positioned at extended source to skin distance (SSD) with a compensator to account for differences in patient thickness, 50% transmission daily lung blocks, and electron chest wall boosts prescribed to 50% of the photon prescription. Clinically relevant metrics were analyzed and compared between the VMAT and 2D plans. RESULTS All VMAT-TBI plans achieved planned target volume (PTV) D90% ≥ 100% of prescription. VMAT-TBI PTV D90% significantly increased (7.1% ± 2.9%, p < .001) compared to the 2D technique, whereas no differences were observed in global Dmax (p < .2) and PTV V110% (p < .4). Compared to the 2D plans, significant decreases in the Dmean to the lungs (-25.6% ± 11.5%, p < .001) and lungs-1 cm (-34.1% ± 10.1%, p < .001) were observed with the VMAT plans. The VMAT technique also enabled decrease of dose to other organs: kidneys Dmean (-32.5% ± 5.0%, p < .001) and lenses Dmax (-5.3% ± 8.1%, p = .03); and in addition, for 2 Gy prescription: testes/ovaries Dmean (-41.5% ± 11.5%, p < .001), brain Dmean (-22.6% ± 5.4%, p = .002), and thyroid Dmean (-18.2% ± 16.0%, p = .03). CONCLUSIONS Superior lung sparing with improved target coverage and similar global Dmax were observed with the VMAT plans as compared to 2D plans. In addition, VMAT-TBI plans provided greater dose reductions in gonads, kidneys, brain, thyroid, and lenses.
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Affiliation(s)
- Nicholas Ngo
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Erik S Blomain
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Eric Simiele
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Ignacio Romero
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Richard T Hoppe
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Susan M Hiniker
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
| | - Nataliya Kovalchuk
- Radiation Oncology Department, Stanford University Cancer Center, Palo Alto, California, USA
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Simiele E, Han B, Skinner L, Pham D, Lewis J, Gensheimer M, Vitzthum L, Chang D, Surucu M, Kovalchuk N. Mitigation of IMRT/SBRT treatment planning errors on the novel RefleXion X1 system using FMEA within Six Sigma framework. Adv Radiat Oncol 2023; 8:101186. [PMID: 37035034 PMCID: PMC10073615 DOI: 10.1016/j.adro.2023.101186] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 01/16/2023] [Indexed: 01/27/2023] Open
Abstract
Purpose The aim of this study was to apply the Six Sigma methodology and failure mode and effect analysis (FMEA) to mitigate errors in intensity modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) treatment planning with the first clinical installation of RefleXion X1. Methods and Materials The Six Sigma approach consisted of 5 phases: define, measure, analyze, improve, and control. The define, measure, and analyze phases consisted of process mapping and an FMEA of IMRT and SBRT treatment planning on the X1. The multidisciplinary team outlined the workflow process and identified and ranked the failure modes associated with the plan check items using the American Association of Physicists in Medicine Task Group 100 recommendations. Items with the highest average risk priority numbers (RPNs) and severity ≥7 were prioritized for automation using the Eclipse Scripting Application Programming Interface (ESAPI). The "improve" phase consisted of developing ESAPI scripts before the clinical launch of X1 to improve efficiency and safety. In the "control" phase, the FMEA ranking was re-evaluated 1 year after clinical launch. Results Overall, 100 plan check items were identified in which the RPN values ranged from 10.2 to 429.0. Fifty of these items (50%) were suitable for automation within ESAPI. Of the 10 highest-risk items, 8 were suitable for automation. Based on the results of the FMEA, 2 scripts were developed: Planning Assistant, used by the planner during preparation for planning, and Automated Plan Check, used by the planner and the plan checker during plan preparation for treatment. After 12 months of clinical use of the X1 and developed scripts, only 3 errors were reported. The average prescript RPN was 138.0, compared with the average postscript RPN of 47.8 (P < .05), signifying a safer process. Conclusions Implementing new technology in the clinic can be an error-prone process in which the likelihood of errors increases with increasing pressure to implement the technology quickly. To limit errors in clinical implementation of the novel RefleXion X1 system, the Six Sigma method was used to identify failure modes, establish quality control checks, and re-evaluate these checks 1 year after clinical implementation.
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Affiliation(s)
- Eric Simiele
- Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, New Brunswick, New Jersey
| | - Bin Han
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Lawrie Skinner
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Daniel Pham
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Jonathan Lewis
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Michael Gensheimer
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Lucas Vitzthum
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Daniel Chang
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Nataliya Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California
- Corresponding author: Nataliya Kovalchuk, PhD
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Niedermayr T, Simiele E, Kidd E. GSOR7 Presentation Time: 9:30 AM. Brachytherapy 2022. [DOI: 10.1016/j.brachy.2022.09.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Marquez C, Hui C, Simiele E, Blomain E, Oh J, Bertaina A, Klein O, Shyr D, Jiang A, Hoppe RT, Kovalchuk N, Hiniker SM. Volumetric modulated arc therapy total body irradiation in pediatric and adolescent/young adult patients undergoing stem cell transplantation: Early outcomes and toxicities. Pediatr Blood Cancer 2022; 69:e29689. [PMID: 35373904 DOI: 10.1002/pbc.29689] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/16/2022] [Accepted: 03/10/2022] [Indexed: 11/09/2022]
Abstract
INTRODUCTION Total body irradiation (TBI) is an important component of many conditioning regimens for hematopoietic stem cell transplantation (HSCT), most commonly used in pediatric and adolescent/young adult (AYA) patients. We aimed to evaluate outcomes and toxicities among pediatric and AYA patients treated with TBI utilizing volumetric modulated arc therapy total body irradiation (VMAT-TBI). METHODS We reviewed pediatric and AYA patients treated with VMAT-TBI at our institution from 2019 to 2021. Data on patient and disease characteristics, treatment details, outcomes and toxicities were collected. Overall survival (OS) and relapse-free survival (RFS) were analyzed using the Kaplan-Meier method. RESULTS Among 38 patients, 16 (42.1%) were treated with myeloablative regimens and 22 (57.9%) with nonmyeloablative regimens. Median age was 7.2 years (range: 1-27) and median follow-up was 8.7 months (range: 1-21). Lungs Dmean was 7.3 ± 0.3 Gy for myeloablative regimens (range: 6.8-7.8). Kidneys were spared to average mean dose of 71.4 ± 4.8% of prescription dose. Gonadal sparing was achieved for patients treated for nonmalignant diseases to Dmean of 0.7 ± 0.1 Gy. No patient experienced primary graft failure; one (2.6%) experienced secondary graft failure. The most common grade 1-2 acute toxicities were nausea (68.4%) and fatigue (55.3%). Mucositis was the most common grade 3-4 acute toxicity, affecting 39.5% of patients. There were no cases of pneumonitis or nephrotoxicity attributable to TBI. CONCLUSION VMAT-TBI offers increased ability to spare organs at risk in pediatric and AYA patients undergoing HSCT, with a favorable acute/subacute toxicity profile and excellent disease control.
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Affiliation(s)
- Cesar Marquez
- Stanford University School of Medicine, Stanford University, Stanford, California, USA
| | - Caressa Hui
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Eric Simiele
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Erik Blomain
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Justin Oh
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Alice Bertaina
- Division of Hematology, Oncology, Stem Cell Transplantation, and Regenerative Medicine, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford, California, USA
| | - Orly Klein
- Division of Hematology, Oncology, Stem Cell Transplantation, and Regenerative Medicine, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford, California, USA
| | - David Shyr
- Division of Hematology, Oncology, Stem Cell Transplantation, and Regenerative Medicine, Department of Pediatrics, Lucile Packard Children's Hospital, Stanford, California, USA
| | - Alice Jiang
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Richard T Hoppe
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Nataliya Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Susan M Hiniker
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
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Simiele E, Capaldi D, Breitkreutz D, Han B, Yeung T, White J, Zaks D, Owens M, Maganti S, Xing L, Surucu M, Kovalchuk N. Treatment planning system commissioning of the first clinical biology‐guided radiotherapy machine. J Appl Clin Med Phys 2022; 23:e13638. [PMID: 35644039 PMCID: PMC9359035 DOI: 10.1002/acm2.13638] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/18/2022] [Accepted: 04/22/2022] [Indexed: 11/09/2022] Open
Abstract
Purpose Methods Results Conclusions
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Affiliation(s)
- Eric Simiele
- Department of Radiation Oncology Stanford University Stanford California USA
| | - Dante Capaldi
- Department of Radiation Oncology Stanford University Stanford California USA
| | - Dylan Breitkreutz
- Department of Radiation Oncology Stanford University Stanford California USA
| | - Bin Han
- Department of Radiation Oncology Stanford University Stanford California USA
| | | | - John White
- RefleXion Medical, Inc. Hayward California USA
| | - Daniel Zaks
- RefleXion Medical, Inc. Hayward California USA
| | | | | | - Lei Xing
- Department of Radiation Oncology Stanford University Stanford California USA
| | - Murat Surucu
- Department of Radiation Oncology Stanford University Stanford California USA
| | - Nataliya Kovalchuk
- Department of Radiation Oncology Stanford University Stanford California USA
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Han B, Capaldi D, Kovalchuk N, Simiele E, White J, Zaks D, Xing L, Surucu M. Beam commissioning of the first clinical biology-guided radiotherapy system. J Appl Clin Med Phys 2022; 23:e13607. [PMID: 35482018 PMCID: PMC9194984 DOI: 10.1002/acm2.13607] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/15/2022] [Accepted: 03/22/2022] [Indexed: 11/28/2022] Open
Abstract
This study reports the beam commissioning results for the first clinical RefleXion Linac. Methods: The X1 produces a 6 MV photon beam and the maximum clinical field size is 40 × 2 cm2 at source‐to‐axis distance of 85 cm. Treatment fields are collimated by a binary multileaf collimator (MLC) system with 64 leaves with width of 0.625 cm and y‐jaw pairs to provide either a 1 or 2 cm opening. The mechanical alignment of the radiation source, the y‐jaw, and MLC were checked with film and ion chambers. The beam parameters were characterized using a diode detector in a compact water tank. In‐air lateral profiles and in‐water percentage depth dose (PDD) were measured for beam modeling of the treatment planning system (TPS). The lateral profiles, PDDs, and output factors were acquired for field sizes from 1.25 × 1 to 40 × 2 cm2 field to verify the beam modeling. The rotational output variation and synchronicity were tested to check the gantry angle, couch motion, and gantry rotation. Results: The source misalignments were 0.049 mm in y‐direction, 0.66% out‐of‐focus in x‐direction. The divergence of the beam axis was 0.36 mm with a y‐jaw twist of 0.03°. Clinical off‐axis treatment fields shared a common center in y‐direction were within 0.03 mm. The MLC misalignment and twist were 0.57 mm and 0.15°. For all measured fields ranging from the size from 1.25 × 1 to 40 × 2 cm2, the mean difference between measured and TPS modeled PDD at 10 cm depth was −0.3%. The mean transverse profile difference in the field core was −0.3% ± 1.1%. The full‐width half maximum (FWHM) modeling was within 0.5 mm. The measured output factors agreed with TPS within 0.8%. Conclusions: This study summarizes our specific experience commissioning the first novel RefleXion linac, which may assist future users of this technology when implementing it into their own clinics.
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Affiliation(s)
- Bin Han
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Dante Capaldi
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Nataliya Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Eric Simiele
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - John White
- RefleXion Medical, Hayward, California, USA
| | | | - Lei Xing
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
| | - Murat Surucu
- Department of Radiation Oncology, Stanford University, Stanford, California, USA
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Kovalchuk N, Simiele E, Skinner L, Yang Y, Howell N, Lewis J, Hui C, Blomain ES, Hoppe RT, Hiniker SM. The Stanford VMAT TBI Technique. Pract Radiat Oncol 2022; 12:245-258. [PMID: 35182803 DOI: 10.1016/j.prro.2021.12.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 11/17/2022]
Abstract
PURPOSE In this work, we describe the technical aspects of the XXX VMAT TBI technique, compare it to other VMAT TBI techniques, and share our initial experience. METHODS From September 2019 to August 2021, 35 patients were treated with VMAT TBI at our institution. Treatment planning was performed using in-house developed automated planning scripts. Organ sparing depended on the regimen: myeloablative (lungs, kidneys, and lenses); non-myeloablative with benign disease (lungs, kidneys, lenses, gonads, brain, and thyroid). Quality assurance was performed using EPID portal dosimetry and Mobius3D. Robustness was evaluated for the first ten patients by performing local and global isocenter shifts of 5 mm. Treatment was delivered using IGRT for every isocenter and every fraction. In-vivo measurements were performed on the matchline between the VMAT and AP/PA fields and on the testes for the first fraction. RESULTS The lungs, lungs-1cm, and kidneys Dmean were consistently spared to 57.6±4.4%, 40.7±5.5%, and 70.0±9.9% of the prescription dose, respectively. Gonadal sparing (Dmean=0.69±0.13 Gy) was performed for all patients with benign disease. The average PTV D1cc was 120.7±6.4% for all patients. The average Gamma passing rate for the VMAT plans was 98.1±1.6% (criteria of 3%/2mm). Minimal differences were observed between Mobius3D- and EclipseAAA-calculated PTV Dmean (0.0±0.3%) and lungs Dmean (-2.5±1.2%). Robustness evaluation showed that the PTV Dmax and lungs Dmean are insensitive to small positioning deviations between the VMAT isocenters (1.1±2.4% and 1.2±1.0%, respectively). The average matchline dose measurement indicated patient setup was reproducible (96.1±4.5% relative to prescription dose). Treatment time, including patient setup and beam-on, was 47.5±9.5 min. CONCLUSIONS The XXX VMAT TBI technique, from simulation to treatment delivery, was presented and compared to other VMAT TBI techniques. Together with publicly shared autoplanning scripts, our technique may provide the gateway for wider adaptation of this technology and the possibility of multi-institutional studies in the cooperative group setting.
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Affiliation(s)
- Nataliya Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Eric Simiele
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Lawrie Skinner
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Yong Yang
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Nicole Howell
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Jonathan Lewis
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Caressa Hui
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Erik S Blomain
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Richard T Hoppe
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States
| | - Susan M Hiniker
- Department of Radiation Oncology, Stanford University, Stanford, California 94305, United States.
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Pham D, Simiele E, Breitkreutz D, Capaldi D, Han B, Surucu M, Oderinde S, Vitzthum L, Gensheimer M, Bagshaw H, Chin A, Xing L, Chang DT, Kovalchuk N. IMRT and SBRT Treatment Planning Study for the First Clinical Biology-Guided Radiotherapy System. Technol Cancer Res Treat 2022; 21:15330338221100231. [PMID: 35579876 PMCID: PMC9118457 DOI: 10.1177/15330338221100231] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Purpose: The first clinical biology-guided radiation therapy (BgRT) system—RefleXionTM X1—was installed and commissioned for clinical use at our institution. This study aimed at evaluating the treatment plan quality and delivery efficiency for IMRT/SBRT cases without PET guidance. Methods: A total of 42 patient plans across 6 cancer sites (conventionally fractionated lung, head, and neck, anus, prostate, brain, and lung SBRT) planned with the EclipseTM treatment planning system (TPS) and treated with either a TrueBeam® or Trilogy® were selected for this retrospective study. For each Eclipse VMAT plan, 2 corresponding plans were generated on the X1 TPS with 10 mm jaws (X1-10mm) and 20 mm jaws (X1-20mm) using our institutional planning constraints. All clinically relevant metrics in this study, including PTV D95%, PTV D2%, Conformity Index (CI), R50, organs-at-risk (OAR) constraints, and beam-on time were analyzed and compared between 126 VMAT and RefleXion plans using paired t-tests. Results: All but 3 planning metrics were either equivalent or superior for the X1-10mm plans as compared to the Eclipse VMAT plans across all planning sites investigated. The Eclipse VMAT and X1-10mm plans generally achieved superior plan quality and sharper dose fall-off superior/inferior to targets as compared to the X1-20mm plans, however, the X1-20mm plans were still considered acceptable for treatment. On average, the required beam-on time increased by a factor of 1.6 across all sites for X1-10mm compared to X1-20mm plans. Conclusions: Clinically acceptable IMRT/SBRT treatment plans were generated with the X1 TPS for both the 10 mm and 20 mm jaw settings.
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Affiliation(s)
- Daniel Pham
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Eric Simiele
- Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Dylan Breitkreutz
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Dante Capaldi
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Bin Han
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Murat Surucu
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | | | - Lucas Vitzthum
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Michael Gensheimer
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Hilary Bagshaw
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Alex Chin
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Lei Xing
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - D T Chang
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
| | - Natalyia Kovalchuk
- Department of Radiation Oncology, 6429Stanford University, Stanford, CA, USA
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Han B, Kovalchuk N, Capaldi D, Simiele E, White J, Purwar A, Yeung T, Maganti S, Mitra A, Voronenko Y, Oderinde O, Shirvani S, Kuduvalli G, Vitzthum L, Chang D, Xing L, Surucu M. First Beam Commissioning Report of a Novel Medical Linear Accelerator Designed for Biologically Guided Radiotherapy. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.1404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kovalchuk N, Blomain E, Ngo N, Simiele E, Skinner L, Hoppe R, Hiniker S. Improved Organ Sparing with Autoplanned VMAT TBI. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Simiele E, Skinner L, Yang Y, Blomain E, Hoppe R, Hiniker S, Kovalchuk N. A Step Towards Making VMAT TBI More Prevalent: Automating the Treatment Planning Process. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Pham D, Breitkreutz D, Simiele E, Capaldi D, Ngo N, Vitzthum L, Gensheimer M, Chin A, Han B, Surucu M, Xing L, Chang D, Kovalchuk N. SBRT Treatment Planning Study for the First Clinical Biology-Guided Radiotherapy System. Int J Radiat Oncol Biol Phys 2021. [DOI: 10.1016/j.ijrobp.2021.07.1490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Simiele E, Niedermayr T, Kidd E. PP06 Presentation Time: 10:50 AM. Brachytherapy 2021. [DOI: 10.1016/j.brachy.2021.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Simiele E, Skinner L, Yang Y, Blomain ES, Hoppe RT, Hiniker SM, Kovalchuk N. A Step Toward Making VMAT TBI More Prevalent: Automating the Treatment Planning Process. Pract Radiat Oncol 2021; 11:415-423. [PMID: 33711488 DOI: 10.1016/j.prro.2021.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 02/08/2021] [Accepted: 02/26/2021] [Indexed: 01/28/2023]
Abstract
PURPOSE Our purpose was to automate the treatment planning process for total body irradiation (TBI) with volumetric modulated arc therapy (VMAT). METHODS AND MATERIALS Two scripts were developed to facilitate autoplanning: the binary plug-in script automating the creation of optimization structures, plan generation, beam placement, and setting of the optimization constraints and the stand-alone executable performing successive optimizations. Ten patients previously treated in our clinic with VMAT TBI were used to evaluate the efficacy of the proposed autoplanning process. Paired t tests were used to compare the dosimetric indices of the produced auto plans to the manually generated clinical plans. In addition, 3 physicians were asked to evaluate the manual and autoplans for each patient in a blinded retrospective review. RESULTS No significant differences were observed between the manual and autoplan global Dmax (P < .893), planning target volume V110% (P < .734), kidneys Dmean (P < .351), and bowel Dmax (P < .473). Significant decreases in the Dmean to the lungs and lungs-1cm (ie, lungs with 1-cm inner margin) volumes of 5.4% ± 6.4% (P < .024) and 6.8% ± 7.4% (P < .017), respectively, were obtained with the autoplans compared with the manual plans. The autoplans were selected 77% of the time by the reviewing physicians as equivalent or superior to the manual plans. The required time for treatment planning was estimated to be 2 to 3 days for the manual plans compared with approximately 3 to 5 hours for the autoplans. CONCLUSIONS Large reductions in planning time without sacrificing plan quality were obtained using the developed autoplanning process compared with manual planning, thus reducing the required effort of the treatment planning team. Superior lung sparing with the same target coverage and similar global Dmax were observed with the autoplans as compared with the manual treatment plans. The developed scripts have been made open-source to improve access to VMAT TBI at other institutions and clinics.
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Affiliation(s)
- E Simiele
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - L Skinner
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Y Yang
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - E S Blomain
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - R T Hoppe
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - S M Hiniker
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - N Kovalchuk
- Department of Radiation Oncology, Stanford University, Stanford, California.
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Simiele E, Viscariello N, DeWerd L. Monte Carlo modeling of the influence of strong magnetic fields on the stem-effect in plastic scintillation detectors used in radiotherapy dosimetry. Med Phys 2021; 48:1381-1394. [PMID: 33283279 DOI: 10.1002/mp.14637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/03/2020] [Accepted: 11/23/2020] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To investigate the impact of strong magnetic fields on the stem-effect in plastic scintillation detectors (PSDs) using Monte Carlo methods. METHODS Prior to building the light guide model, the properties of the Čerenkov process in GEANT4 were investigated by simulating depth-dose and depth-Čerenkov emission profiles in water as functions of Čerenkov process input parameters. In addition, profile simulations were performed for magnetic field strengths ranging from 0 T to 1.5 T. A PMMA light guide was constructed in GEANT4 using data from the manufacturer and literature. Simulations were performed with the model as functions of depth and fiber-beam angle where the simulated stem-effect spectrum and the Čerenkov light ratio (CLR) were scored and compared to measured data in the literature. The light guide optical properties were iteratively adjusted until agreement between the simulated and measured data was achieved. Simulations were performed with the validated model as functions of depth and magnetic field strength and the simulated data were compared to measured data in the literature. The model was also used to evaluate the sensitivity of the CLR to the various optical properties of the light guide in different irradiation conditions. RESULTS No significant changes in the depth-dose or depth-Čerenkov emission profiles were observed with step-size restrictions imposed by the Čerenkov process input parameters, which was attributed to the condensed history algorithm and transport parameters used in this work. Similar changes in the depth-dose and depth-Čerenkov emission profiles were observed with increasing magnetic field strength, which indicates the Čerenkov process is not adversely impacted by the presence of the magnetic field. Following optimization of the light guide optical properties, agreement within two standard deviations was observed between the simulated and measured optical data for all validation geometries considered. Agreement within one standard deviation was observed between the simulated and measured data for all depths and field strengths ≥0 T whereas discrepancies were observed for magnetic field strengths <-0.35 T. These significant differences were attributed to insufficient measurement data for this irradiation configuration during model validation. Of the light guide optical properties investigated, the fluorescence signal had the greatest impact on the CLR sensitivity to the magnetic field. CONCLUSIONS No significant change in the Čerenkov emission per dose in water was observed for magnetic field strengths up to 1.5 T. The nominal fiber fluorescence signal was found to have a significant impact on the CLR sensitivity to varying irradiation conditions where changes up to 11.7% were observed whereas the mirror reflectivity and fiber attenuation had a modest impact with maximum CLR changes of 2.6% and 1.2% relative to 0 T, respectively. The results of this work suggest light guides with low fiber fluorescence should be used with PSDs for dosimetry measurements in magnetic fields to minimize the impact of the magnetic field on the CLR correction.
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Affiliation(s)
- E Simiele
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - N Viscariello
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - L DeWerd
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, 53705, USA
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Vasudevan V, Huang C, Simiele E, Yu L, Xing L, Schuler E. Combining Monte Carlo with Deep Learning: Predicting High-resolution, Low-noise Dose Distributions Using a Generative Adversarial Network for Fast and Precise Monte Carlo Simulations. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.2157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Blomain E, Skinner L, Simiele E, Yang Y, Howell N, Hiniker S, Hoppe R. Improved Lung Sparing During Total Body Irradiation Using a VMAT Technique Versus a 2D Lung Block Approach: Preliminary Single-institutional Experience. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.2372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Simiele E, Kapsch RP, Ankerhold U, Culberson W, DeWerd L. Technical note: characterization of spectral changes with measurement geometry and magnetic field strength in light guides used for scintillation dosimetry. ACTA ACUST UNITED AC 2020; 65:11NT01. [DOI: 10.1088/1361-6560/ab8afa] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
The purpose of this work was to investigate the accuracy and efficiency of electron transport in GEANT4 with and without a magnetic field present. Fano cavity simulations were performed in GEANT4 version 10.02 and 10.04.p01 using two multiple scattering (MSC) algorithms for two slab and one pseudo-ion chamber geometries. An iterative approach was used to optimize the transport parameters to obtain agreement with theory. Similar to previous works, the step lengths had to be severely restricted to obtain agreement with theory when using the Urban MSC model in GEANT4 v10.02. Using the Goudsmit-Saunderson MSC model with the UseSafetyPlus MSC step limitation in GEANT4 v10.04.p01 limited the maximum discrepancy from theory to 0.5%. Minor adjustments to the transport parameters were needed to obtain agreement within 0.16% of theory for all simulation configurations without a magnetic field present. The maximum deviation from theory was within 2% for all simulation configurations in the presence of a magnetic field except for two setups that exhibited discrepancies of up to 10.8%. This anomalous behavior was mitigated by forcing single scattering within the detector gas volume. Further adjustments to the transport parameters resulted in agreement with theory at the 0.21% level. Agreement with theory in the absence of a magnetic field can be obtained without significantly restricting the step size if the Goudsmit-Saunderson MSC model is used with the UseSafetyPlus MSC step limitation in GEANT4 v10.04.p01. The large discrepancies from theory observed for two simulation setups with a magnetic field present were attributed to an issue with energy loss sampling over a step when strict magnetic field transport parameters are used. This problem can be corrected by forcing single scattering within the detector gas volume; however, more work is needed to identify the cause of this anomalous behavior. This work has shown that GEANT4 can perform accurate electron transport with and without a magnetic field present without applying significant step-size reductions.
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Affiliation(s)
- E Simiele
- Author to whom any correspondence should be addressed
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Simiele E, Kapsch RP, Ankerhold U, Culberson W, DeWerd L. Spectral characterization of plastic scintillation detector response as a function of magnetic field strength. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1361-6560/aab56c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Simiele E, Smith B, Culberson W. SU-F-T-73: Experimental Determination of the Effective Point of Measurement in Electron Beams Using a Commercial Scintillation Detector. Med Phys 2016. [DOI: 10.1118/1.4956209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Simiele E, Culberson W. SU-E-T-108: An Investigation of Cerenkov Light Production in the Exradin W1 Scintillator Under Various Measurement Conditions. Med Phys 2015. [DOI: 10.1118/1.4924469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Taneja S, Fru LC, Desai V, Lentz J, Lin C, Scarpelli M, Simiele E, Trestrail A, Bednarz B. SU-F-BRA-16: Development of a Radiation Monitoring Device Using a Low-Cost CCD Camera Following Radionuclide Therapy. Med Phys 2015. [DOI: 10.1118/1.4925227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Wood M, Desai V, Simiele E, Taneja S, DeWerd L. TU-F-BRE-06: Flattening-Filter-Free Beam Quality Correction Factor Determination Using Experimental and Monte Carlo Methods. Med Phys 2014. [DOI: 10.1118/1.4889314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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