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Nakaichi T, Okamoto H, Kon M, Takaso K, Aikawa A, Nakamura S, Ijima K, Chiba T, Nakayama H, Takemori M, Mikasa S, Fujii K, Urago Y, Goka T, Shimizu Y, Igaki H. Commissioning and performance evaluation of commercially available mobile imager for image guided total body irradiation. J Appl Clin Med Phys 2022; 24:e13865. [PMID: 36573258 PMCID: PMC10113699 DOI: 10.1002/acm2.13865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 08/19/2022] [Accepted: 11/19/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The setup of lung shield (LS) in total body irradiation (TBI) with the computed radiography (CR) system is a time-consuming task and has not been quantitatively evaluated. The TBI mobile imager (TBI-MI) can solve this problem through real-time monitoring. Therefore, this study aimed to perform commissioning and performance evaluation of TBI-MI to promote its use in clinical practice. METHODS The source-axis distance in TBI treatment, TBI-MI (CNERGY TBI, Cablon Medical B.V.), and the LS position were set to 400, 450, and 358 cm, respectively. The evaluation items were as follows: accuracy of image scaling and measured displacement error of LS, image quality (linearity, signal-to-noise ratio, and modulation transfer function) using an EPID QC phantom, optimal thresholding to detect intra-fractional motion in the alert function, and the scatter radiation dose from TBI-MI. RESULTS The accuracy of image scaling and the difference in measured displacement of the LS was <4 mm in any displacements and directions. The image quality of TBI imager was slightly inferior to the CR image but was visually acceptable in clinical practice. The signal-to-noise ratio was improved at high dose rate. The optimal thresholding value to detect a 10-mm body displacement was determined to be approximately 5.0%. The maximum fraction of scattering radiation to irradiated dose was 1.7% at patient surface. CONCLUSION MI-TBI can quantitatively evaluate LS displacement with acceptable image quality. Furthermore, real-time monitoring with alert function to detect intrafraction patient displacement can contribute to safe TBI treatment.
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Affiliation(s)
- Tetsu Nakaichi
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Hiroyuki Okamoto
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Mitsuhiro Kon
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
- Department of Radiological Technology Radiological OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Kazuki Takaso
- Department of Radiological Technology Radiological OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Ako Aikawa
- Department of Radiological Technology Radiological OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Satoshi Nakamura
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Kotaro Ijima
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Takahito Chiba
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Hiroki Nakayama
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
- Department of Radiological SciencesGraduate School of Human Health ScienceTokyo Metropolitan UniversityArakawa‐kuTokyoJapan
| | - Mihiro Takemori
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
- Department of Radiological SciencesGraduate School of Human Health ScienceTokyo Metropolitan UniversityArakawa‐kuTokyoJapan
| | - Shohei Mikasa
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Kyohei Fujii
- Department of Radiation SciencesKomazawa UniversitySetagaya‐kuTokyoJapan
| | - Yuka Urago
- Radiation Safety and Quality Assurance DivisionNational Cancer Center HospitalChuo‐kuTokyoJapan
- Department of Radiological SciencesGraduate School of Human Health ScienceTokyo Metropolitan UniversityArakawa‐kuTokyoJapan
| | - Tomonori Goka
- Department of Radiological Technology Radiological OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Yuri Shimizu
- Department of Radiation OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
| | - Hiroshi Igaki
- Department of Radiation OncologyNational Cancer Center HospitalChuo‐kuTokyoJapan
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Hoseinnezhad Zarghani E, Geraily G, Hadisinia T. Comparison of different TBI techniques in terms of dose homogeneity - review study. Cancer Radiother 2021; 25:380-389. [PMID: 33431295 DOI: 10.1016/j.canrad.2020.12.004] [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: 12/05/2019] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 10/22/2022]
Abstract
Total body irradiation (TBI) is a kind of external beam radiotherapy, used in conjunction with chemotherapy with the purpose of immunosuppression. Since the target in TBI is the whole body, so achieving uniform dose distribution throughout the entire body during TBI is necessary. As recommended by AAPM dose variation must be within ±10% of the prescription dose. With the evidences from literature there is limited substantiation to consider a treatment method better than others, but with regard to the size of the treatment room, workload of the radiotherapy department and prevalent technology used within each treatment department it is recommended to make the suitable and optimum method in each department. In this work, a review study was performed on different TBI techniques with the purpose of assessment and comparison of dose distribution homogeneity in these methods.
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Affiliation(s)
- E Hoseinnezhad Zarghani
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - G Geraily
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - T Hadisinia
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Ouyang L, Folkerts M, Zhang Y, Hrycushko B, Lamphier R, Lee P, Chambers E, Ramirez E, Reynolds R, Yan Y, Jiang SB, Timmerman R, Desai N, Abdulrahman R, Gu X. Volumetric modulated arc therapy based total body irradiation: Workflow and clinical experience with an indexed rotational immobilization system. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2017. [DOI: 10.1016/j.phro.2017.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Park SY, Kim JI, Joo YH, Lee JC, Park JM. Total body irradiation with a compensator fabricated using a 3D optical scanner and a 3D printer. Phys Med Biol 2017; 62:3735-3756. [PMID: 28327469 DOI: 10.1088/1361-6560/aa6866] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We propose bilateral total body irradiation (TBI) utilizing a 3D printer and a 3D optical scanner. We acquired surface information of an anthropomorphic phantom with the 3D scanner and fabricated the 3D compensator with the 3D printer, which could continuously compensate for the lateral missing tissue of an entire body from the beam's eye view. To test the system's performance, we measured doses with optically stimulated luminescent dosimeters (OSLDs) as well as EBT3 films with the anthropomorphic phantom during TBI without a compensator, conventional bilateral TBI, and TBI with the 3D compensator (3D TBI). The 3D TBI showed the most uniform dose delivery to the phantom. From the OSLD measurements of the 3D TBI, the deviations between the measured doses and the prescription dose ranged from -6.7% to 2.4% inside the phantom and from -2.3% to 0.6% on the phantom's surface. From the EBT3 film measurements, the prescription dose could be delivered to the entire body of the phantom within ±10% accuracy, except for the chest region, where tissue heterogeneity is extreme. The 3D TBI doses were much more uniform than those of the other irradiation techniques, especially in the anterior-to-posterior direction. The 3D TBI was advantageous, owing to its uniform dose delivery as well as its efficient treatment procedure.
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Affiliation(s)
- So-Yeon Park
- Department of Radiation Oncology, Seoul National University Hospital, Seoul 03080, Republic of Korea. Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 03080, Republic of Korea. Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Republic of Korea. Center for Convergence Research on Robotics, Advanced Institutes of Convergence Technology, Suwon 16229, Republic of Korea
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Chakarova R, Krantz M. A Monte Carlo evaluation of beam characteristics for total body irradiation at extended treatment distances. J Appl Clin Med Phys 2014; 15:4708. [PMID: 24892344 PMCID: PMC5711064 DOI: 10.1120/jacmp.v15i3.4708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 12/11/2013] [Accepted: 12/09/2013] [Indexed: 11/25/2022] Open
Abstract
The aim is to study beam characteristics at large distances when focusing on the electron component. In particular, to investigate the utility of spoilers with various thicknesses as an electron source, as well as the effect of different spoiler‐to‐surface distances (STSD) on the beam characteristics and, consequently, on the dose in the superficial region. A MC model of a 15 MV Varian accelerator, validated earlier by experimental data at isocenter and extended distances used in large‐field total body irradiation, is applied to evaluate beam characteristics at distances larger than 400 cm. Calculations are carried out using BEAMnrc/DOSXYZnrc code packages and phase space data are analyzed by the beam data processor BEAMdp. The electron component of the beam is analyzed at isocenter and extended distances, with and without spoilers as beam modifiers, assuming vacuum or air surrounding the accelerator head. Spoiler thickness of 1.6 cm is found to be optimal compared to thicknesses of 0.8 cm and 2.4 cm. The STSD variations should be taken into account when treating patients, in particular when the treatment protocols are based on a fixed distance to the patient central sagittal plane, and also, in order to maintain high dose in the superficial region. PACS numbers: 87.55.D‐, 87.55.de, 87.55.K‐
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Jahnke A, Jahnke L, Molina-Duran F, Ehmann M, Kantz S, Steil V, Wenz F, Glatting G, Lohr F, Polednik M. Arc therapy for total body irradiation – A robust novel treatment technique for standard treatment rooms. Radiother Oncol 2014; 110:553-7. [DOI: 10.1016/j.radonc.2013.12.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 11/05/2013] [Accepted: 12/15/2013] [Indexed: 12/20/2022]
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Total body irradiation with step translation and dynamic field matching. BIOMED RESEARCH INTERNATIONAL 2013; 2013:216034. [PMID: 23956971 PMCID: PMC3713376 DOI: 10.1155/2013/216034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Accepted: 05/31/2013] [Indexed: 11/18/2022]
Abstract
The purpose of this study is to develop a total body irradiation technique that does not require additional devices or sophisticated processes to overcome the space limitation of a small treatment room. The technique aims to deliver a uniform dose to the entire body while keeping the lung dose within the tolerance level. The technique treats the patient lying on the floor anteriorly and posteriorly. For each AP/PA treatment, two complementary fields with dynamic field edges are matched over an overlapped region defined by the marks on the body surface. A compensator, a spoiler, and lung shielding blocks were used during the treatment. Moreover, electron beams were used to further boost the chest wall around the lungs. The technique was validated in a RANDO phantom using GAFCHROMIC films. Dose ratios at different body sites along the midline ranged from 0.945 to 1.076. The dose variation in the AP direction ranged from 96.0% to 104.6%. The dose distribution in the overlapped region ranged from 98.5% to 102.8%. Lateral dose profiles at abdomen and head revealed 109.8% and 111.7% high doses, respectively, at the body edges. The results confirmed that the technique is capable of delivering a uniform dose distribution to the midline of the body in a small treatment room while keeping the lung dose within the tolerance level.
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Lavallee MC, Aubin S, Larochelle M, Vallieres I, Beaulieu L. 3D heterogeneous dose distributions for total body irradiation patients. J Appl Clin Med Phys 2011; 12:3416. [PMID: 21844851 PMCID: PMC5718646 DOI: 10.1120/jacmp.v12i3.3416] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 02/14/2011] [Accepted: 02/11/2011] [Indexed: 11/23/2022] Open
Abstract
One major objective of total body irradiation (TBI) treatments is to deliver a uniform dose in the entire body of the patient. Looking at 3D dose distributions for constant speed (CstSpeed) and variable speed (VarSpeed) translating couch TBI treatments, dose uniformity and the effect of body heterogeneities were evaluated. This study was based on retrospective dose calculations of 10 patients treated with a translating couch TBI technique. Dose distributions for CstSpeed and VarSpeed TBI treatments have been computed with Pinnacle3 treatment planning system in homogeneous (Homo) and heterogeneous (Hetero) dose calculation modes. A specific beam model was implemented in Pinnacle3 to allow an accurate dose calculation adapted for TBI special aspects. Better dose coverages were obtained with Homo/VarSpeed treatments compared to Homo/CstSpeed cases including smaller overdosage areas. Large differences between CstSpeed and VarSpeed dose calculations were observed in the brain, spleen, arms, legs, and lateral parts of the abdomen (differences between V100% mean values up to 57.5%). Results also showed that dose distributions for patients treated with CstSpeed TBI greatly depend on the patient morphology, especially for pediatric and overweight cases. Looking at heterogeneous dose calculations, underdosages (2%-5%) were found in high-density regions (e.g., bones), while overdosages (5%-15%) were found in low-density regions (e.g., lungs). Overall, Homo/CstSpeed and Hetero/VarSpeed dose distributions showed more hot spots than Homo/VarSpeed and were greatly dependent on patient anatomy. CstSpeed TBI treatments allow a simple optimization process but lead to less dose uniformity due to the patient anatomy. VarSpeed TBI treatments require more complex dose optimization, but lead to a better dose uniformity independent of the patient morphology. Finally, this study showed that heterogeneities should be considered in dose calculations in order to obtain a better optimization and, therefore, to improve dose uniformity.
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Affiliation(s)
- Marie-Claude Lavallee
- Département de Radio-Oncologie et Centre de Recherche en Cancérologie, CHUQ Pavillon L'Hôtel-Dieu de Québec, Canada.
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Hussain A, Villarreal-Barajas JE, Dunscombe P, Brown DW. Aperture modulated, translating bed total body irradiation. Med Phys 2011; 38:932-41. [PMID: 21452729 DOI: 10.1118/1.3534196] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Total body irradiation (TBI) techniques aim to deliver a uniform radiation dose to a patient with an irregular body contour and a heterogeneous density distribution to within +/-10% of the prescribed dose. In the current article, the authors present a novel, aperture modulated, translating bed TBI (AMTBI) technique that produces a high degree of dose uniformity throughout the entire patient. METHODS The radiation beam is dynamically shaped in two dimensions using a multileaf collimator (MLC). The irregular surface compensation algorithm in the Eclipse treatment planning system is used for fluence optimization, which is performed based on penetration depth and internal inhomogeneities. Two optimal fluence maps (AP and PA) are generated and beam apertures are created to deliver these optimal fluences. During treatment, the patient/phantom is translated on a motorized bed close to the floor (source to bed distance: 204.5 cm) under a stationary radiation beam with 0 degree gantry angle. The bed motion and dynamic beam apertures are synchronized. RESULTS The AMTBI technique produces a more homogeneous dose distribution than fixed open beam translating bed TBI. In phantom studies, the dose deviation along the midline is reduced from 10% to less than 5% of the prescribed dose in the longitudinal direction. Dose to the lung is reduced by more than 15% compared to the unshielded fixed open beam technique. At the lateral body edges, the dose received from the open beam technique was 20% higher than that prescribed at umbilicus midplane. With AMTBI the dose deviation in this same region is reduced to less than 3% of the prescribed dose. Validation of the technique was performed using thermoluminescent dosimeters in a Rando phantom. Agreement between calculation and measurement was better than 3% in all cases. CONCLUSIONS A novel, translating bed, aperture modulated TBI technique that employs dynamically shaped MLC defined beams is shown to improve dose uniformity in three dimensions. In comparison with the fixed open beam TBI technique, homogeneity of dose distribution is greatly improved.
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Affiliation(s)
- Amjad Hussain
- Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2, Canada.
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Dosimetric Study and Verification of Total Body Irradiation Using Helical Tomotherapy and its Comparison to Extended SSD Technique. Med Dosim 2010; 35:243-9. [DOI: 10.1016/j.meddos.2009.07.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 07/08/2009] [Accepted: 07/16/2009] [Indexed: 11/18/2022]
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Abstract
The recent discussion and debate about the use of in vivo dosimetry as a routine component of the radiotherapy treatment process has not included the limitations introduced by the physical characteristics of the detectors. Although a robust calibration procedure will ensure acceptable uncertainties in the measurements of tumour dose, further work is required to confirm the accuracy of critical organ measurements with a diode or a thermoluminescent dosemeter outside the main field owing to limitations caused by a non-uniform X-ray energy response of the detector, differences between the X-ray energy spectrum inside and outside the main field, and contaminating electrons.
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Lavallée MC, Aubin S, Chrétien M, Larochelle M, Beaulieu L. Attenuator design for organs at risk in total body irradiation using a translation technique. Med Phys 2008; 35:1663-9. [DOI: 10.1118/1.2899999] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Gallina P, Rosati G, Rossi A. Implementation of a water compensator for total body irradiation. IEEE Trans Biomed Eng 2005; 52:1741-7. [PMID: 16235659 DOI: 10.1109/tbme.2005.855715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This paper presents the design, implementation, and testing of an integrated system for improving dose homogeneity in total body irradiation (TBI). TBI is a radiation therapy technique that consists in delivering a uniform X-ray dose to the entire body of the patient. Because of variations in patient's tissues thickness and density, achieving a uniform dose over the entire body is one of the major challenges in TBI. The system proposed in this paper, whose main goal is to compensate for tissues heterogeneities, is made up of a translating bed, a linear accelerator, a vision system for body thickness assessment, a dynamically controlled water filter, and a main control unit. The water filter, placed between the X-ray source and the patient, is made up of an array of 70 small water containers (cells). The water level in each cell is controlled in real time, so as to modify the dose distribution both in the transverse direction and in the longitudinal direction. A prototype of the water filter system was implemented and tested, achieving good results in terms of dose uniformity.
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Affiliation(s)
- Paolo Gallina
- Department of Energetics, University of Trieste, 34127 Trieste, Italy.
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Sarfaraz M, Yu C, Chen DJ, Der L. A translational couch technique for total body irradiation. J Appl Clin Med Phys 2001; 2:201-9. [PMID: 11686741 PMCID: PMC5726011 DOI: 10.1120/jacmp.v2i4.2597] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2001] [Accepted: 08/27/2001] [Indexed: 11/23/2022] Open
Abstract
We have constructed a computer controlled translational couch to administer total body irradiation reproducibly and safely. The system has replaced the previous stationary anterior-posterior technique in our institution and 30 plus patients have been treated with it so far. In this technique, patients comfortably lie on a couch in supine and prone positions and are transported slowly through a narrow beam with the gantry in an upright position. Dose to the patient is determined by the couch velocity that is calculated based on physical parameters such as patient's dimensions, beam geometry, and machine dose rate. In our design, the couch velocity is continuously updated to compensate for machine dose rate fluctuations. The translational couch technique provides better dose uniformity within the patient compared to fixed beam techniques, and allows a more precise shielding block placement for organs at risk. At the same time, it presents a special challenge for dosimetry calculations. A dosimetry parameter is introduced that converts the moving beam output to the fixed beam output factor. Based on this factor, a simple dosimetry calculation method has been developed that takes advantage of conventional dosimetry parameters, eliminating extensive dosimetry measurements. Multiple point dose measurements within a phantom confirmed the validity of the calculation method.
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Affiliation(s)
- M Sarfaraz
- Radiation Oncology Department, University of Maryland Medical System, 22 South Greene Street, Baltimore, Maryland 21201, USA
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Papiez L, Montebello J, DesRosiers C, Papiez E. The clinical application of dynamic shielding and imaging in moving table total body irradiation. Radiother Oncol 1999; 51:219-24. [PMID: 10435817 DOI: 10.1016/s0167-8140(99)00048-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The moving table technique for total body irradiation (MTT TBI) has some advantages in regard to dose homogeneity, patient positioning and comfort. However, divergence of the radiation field coupled with patient motion necessitates corresponding motion of the shielding blocks and verification film so that penumbra is minimized. MTT TBI system is presented, together with dose calculations, incorporating moving trays for shields and film to ensure dose delivery with minimal penumbra of the blocked field.
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Affiliation(s)
- L Papiez
- Department of Radiation Oncology, Indiana University, Indianapolis, USA
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