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Johnson D, Li HH, Kimler BF. Dosimetry: Was and Is an Absolute Requirement for Quality Radiation Research. Radiat Res 2024; 202:102-129. [PMID: 38954476 DOI: 10.1667/rade-24-00107.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 05/09/2024] [Indexed: 07/04/2024]
Abstract
This review aims to trace the evolution of dosimetry, highlight its significance in the advancement of radiation research, and identify the current trends and methodologies in the field. Key historical milestones, starting with the first publications in the journal in 1954, will be synthesized before addressing contemporary practices in radiation medicine and radiobiological investigation. Finally, possibilities for future opportunities in dosimetry will be offered. The overarching goal is to emphasize the indispensability of accurate and reproducible dosimetry in enhancing the quality of radiation research and practical applications of ionizing radiation.
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Affiliation(s)
- Daniel Johnson
- Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, Kansas 66160-7321
| | - H Harold Li
- Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, Kansas 66160-7321
| | - Bruce F Kimler
- Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, Kansas 66160-7321
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De Deene Y. Radiation Dosimetry by Use of Radiosensitive Hydrogels and Polymers: Mechanisms, State-of-the-Art and Perspective from 3D to 4D. Gels 2022; 8:599. [PMID: 36135311 PMCID: PMC9498652 DOI: 10.3390/gels8090599] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/07/2022] [Accepted: 09/10/2022] [Indexed: 12/22/2022] Open
Abstract
Gel dosimetry was developed in the 1990s in response to a growing need for methods to validate the radiation dose distribution delivered to cancer patients receiving high-precision radiotherapy. Three different classes of gel dosimeters were developed and extensively studied. The first class of gel dosimeters is the Fricke gel dosimeters, which consist of a hydrogel with dissolved ferrous ions that oxidize upon exposure to ionizing radiation. The oxidation results in a change in the nuclear magnetic resonance (NMR) relaxation, which makes it possible to read out Fricke gel dosimeters by use of quantitative magnetic resonance imaging (MRI). The radiation-induced oxidation in Fricke gel dosimeters can also be visualized by adding an indicator such as xylenol orange. The second class of gel dosimeters is the radiochromic gel dosimeters, which also exhibit a color change upon irradiation but do not use a metal ion. These radiochromic gel dosimeters do not demonstrate a significant radiation-induced change in NMR properties. The third class is the polymer gel dosimeters, which contain vinyl monomers that polymerize upon irradiation. Polymer gel dosimeters are predominantly read out by quantitative MRI or X-ray CT. The accuracy of the dosimeters depends on both the physico-chemical properties of the gel dosimeters and on the readout technique. Many different gel formulations have been proposed and discussed in the scientific literature in the last three decades, and scanning methods have been optimized to achieve an acceptable accuracy for clinical dosimetry. More recently, with the introduction of the MR-Linac, which combines an MRI-scanner and a clinical linear accelerator in one, it was shown possible to acquire dose maps during radiation, but new challenges arise.
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Affiliation(s)
- Yves De Deene
- Liverpool & Macarthur Cancer Therapy Centres, Liverpool, NSW 1871, Australia; or
- Ingham Institute, Liverpool, NSW 2170, Australia
- School of Science, Western Sydney University, Penrith, NSW 2751, Australia
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Mohyedin MZ, Zin HM, Adenan MZ, Abdul Rahman AT. A Review of PRESAGE Radiochromic Polymer and the Compositions for Application in Radiotherapy Dosimetry. Polymers (Basel) 2022; 14:2887. [PMID: 35890665 PMCID: PMC9320230 DOI: 10.3390/polym14142887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/02/2022] [Accepted: 07/06/2022] [Indexed: 02/01/2023] Open
Abstract
Recent advances in radiotherapy technology and techniques have allowed a highly conformal radiation to be delivered to the tumour target inside the body for cancer treatment. A three-dimensional (3D) dosimetry system is required to verify the accuracy of the complex treatment delivery. A 3D dosimeter based on the radiochromic response of a polymer towards ionising radiation has been introduced as the PRESAGE dosimeter. The polyurethane dosimeter matrix is combined with a leuco-dye and a free radical initiator, whose colour changes in proportion to the radiation dose. In the previous decade, PRESAGE gained improvement and enhancement as a 3D dosimeter. Notably, PRESAGE overcomes the limitations of its predecessors, the Fricke gel and the polymer gel dosimeters, which are challenging to fabricate and read out, sensitive to oxygen, and sensitive to diffusion. This article aims to review the characteristics of the radiochromic dosimeter and its clinical applications. The formulation of PRESAGE shows a delicate balance between the number of radical initiators, metal compounds, and catalysts to achieve stability, optimal sensitivity, and water equivalency. The applications of PRESAGE in advanced radiotherapy treatment verifications are also discussed.
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Affiliation(s)
- Muhammad Zamir Mohyedin
- School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia;
- Centre of Astrophysics & Applied Radiation, Institute of Science, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia
| | - Hafiz Mohd Zin
- Advanced Medical & Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas 13700, Penang, Malaysia;
| | - Mohd Zulfadli Adenan
- Centre of Medical Imaging, Faculty of Health Sciences, Universiti Teknologi MARA, Cawangan Selangor Campus of Puncak Alam, Puncak Alam 42300, Selangor, Malaysia;
| | - Ahmad Taufek Abdul Rahman
- School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia;
- Centre of Astrophysics & Applied Radiation, Institute of Science, Universiti Teknologi MARA, Shah Alam 40450, Selangor, Malaysia
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Aliasgharzadeh A, Anaraki V, Khoramian D, Ghorbani M, Farhood B. The impact of various amounts of fabricating components on the response of PASSAG polymer gel dosimeter: An optimization study. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2021.109804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Maras P, Jaszczak M, Kozicki M. Basic features of VIC-T dosimeter with spiral CT readout, CT scanning conditions and data processing with a new polyGeVero-CT software package. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Development and Application of MAGIC-f Gel in Cancer Research and Medical Imaging. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11177783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Much of the complex medical physics work requires radiation dose delivery, which requires dosimeters to accurately measure complex three-dimensional dose distribution with good spatial resolution. MAGIC-f polymer gel is one of the emerging new dosimeters widely used in medical physics research. The purpose of this study was to present an overview of polymer gel dosimetry, using MAGIC-f gel, including its composition, manufacture, imaging, calibration, and application to medical physics research. In this review, the history of polymer gel development is presented, along with the applications so far. Moreover, the most important experiments/applications of MAGIC-f polymer gel are discussed to illustrate the behavior of gel on different conditions of irradiation, imaging, and manufacturing techniques. Finally, various future works are suggested based on the past and present works on MAGIC-f gel and polymer gel in general, with the hope that these bits of knowledge can provide important clues for future research on MAGIC-f gel as a dosimeter.
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Nezhad ZA, Geraily G, Parwaie W, Zohari S. A novel investigation of the effect of different concentrations of methacrylic acid on the dose response of MAGAT gel dosimeter in intraoperative radiotherapy. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2020.109214] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Taño JE, Hayashi SI, Hirota S, Gonzales CAB, Yasuda H. Effect of the glucono-δ-lactone concentration on the sensitivity and stability of PVA-GTA-I radiochromic gel dosimeter. RADIAT MEAS 2020. [DOI: 10.1016/j.radmeas.2020.106311] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Xie WH, Su CT, Kao YCJ, Chang TH, Chang YJ, Yao CH, Hsieh BY. Technical Note: Radiotherapy dose characterization of gel dosimetry using shear wave elasticity imaging. Med Phys 2020; 47:1404-1410. [PMID: 31950500 DOI: 10.1002/mp.14020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/26/2019] [Accepted: 12/26/2019] [Indexed: 12/31/2022] Open
Abstract
PURPOSE Radiotherapy is an effective treatment for many types of cancer in clinical settings. Gel dosimetry has the potential to record three-dimensional (3D) dose distribution compared to a conventional ion chamber. As the elasticity of the gel is altered after irradiation due to gel polymerization, we aim to measure the dose recorded in gel dosimetry with ultrasonic shear wave elasticity imaging (SWEI), a nondestructive and quantitative elasticity imaging tool. METHODS In this study, a cylindrical N-isopropylacrylamide (NIPAM) polymer gel with a diameter of 10 cm and a height of 10 cm and with cellulose as an ultrasonic scatterer was irradiated by a linear accelerator with the irradiation parameters of 6 MV x-ray, dose rate of 100 cGy/min and field size of 10 × 20 mm2 . The six gel phantoms were irradiated with the dose of 0, 1, 3, 5, 8, or 10 Gy. The gel phantoms were measured with SWEI at 24, 36, and 48 h after x-ray irradiation. The two-dimensional (2D) shear wave velocity and Young's modulus maps corresponding to x-ray dose distribution were reconstructed following a time-of-flight reconstruction from a set of time-series displacement maps. The spatial resolution of the reconstructed SWEI image is ~1 mm. RESULTS Our results show that the elastic modulus increases linearly as irradiation dose increases (R2 = 0.94 at 24 h, R2 = 0.98 at 36 h, R2 = 0.98 at 48 h), suggesting that the gel elasticity is highly associated with x-ray irradiation dose at 36 h post irradiation, and the dose resolution was 0.66 kPa/Gy. From the 3D elastic modulus maps, the dose distribution along the depth and lateral direction can be reflected in the NIPAM gel dosimetry using SWEI as well. CONCLUSIONS In this study, the irradiated NIPAM gel phantom was quantitatively measured with SWEI for the first time to read the dose distribution recorded in the gel dosimetry. The results suggest that the gel elasticity is highly associated with x-ray irradiation dose. In the future, 2D/or 3D dose distribution from intensity modulated radiotherapy (IMRT) or other potential particle radiotherapy will be measured and reconstructed with SWEI and compared with the dose map from a treatment planning system (TPS) in the clinic.
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Affiliation(s)
- Wei-Huan Xie
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Chun-Ting Su
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Yu-Chieh Jill Kao
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.,Neuroscience Research Center, Taipei Medical University, Taipei, Taiwan.,Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Tung-Hao Chang
- Department of Radiation Oncology, Changhua Christian Hospital, Changhua City, Taiwan
| | - Yuan-Jen Chang
- Department of Aerospace and System Engineering, Feng-Chia University, Taichung, Taiwan
| | - Chun-Hsu Yao
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan.,School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Biomaterials Translational Research Center, China Medical University Hospital, Taichung, Taiwan.,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, Taiwan
| | - Bao-Yu Hsieh
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
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Clinical radiotherapy application of N-vinylpyrrolidone-containing 3D polymer gel dosimeters with remote external MR-reading. Phys Med 2020; 69:134-146. [PMID: 31901838 DOI: 10.1016/j.ejmp.2019.11.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/25/2019] [Accepted: 11/15/2019] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Advanced 3D dosimetry is required for verifications of complex dose distributions in modern radiotherapy. Two 3D polymer gel dosimeters, coupled with magnetic resonance (MR) imaging (3 T MRI) readout and data processing with polyGeVero® software, were tested for the verification of calculated 3D dose distributions by a treatment planning system (TPS) and ArcCHECK®-3DVH®, related to eradication of a lung tumour. METHODS N-vinylpyrrolidone-containing 3D polymer gel dosimeters were used: VIC (containing ascorbic acid and copper sulfate pentahydrate) and VIC-T (containing tetrakis(hydroxymethyl)phosphonium chloride). Three remote centers were involved in the dosimeters preparation and irradiation (Poland), and MRI (Austria). Cross beam calibration of the dosimeters and verification of a 3D dose distribution calculated with an Eclipse External Beam TPS and ArcCHECK®-3DVH® were performed. The 3D-to-3D comparisons of the VIC and VIC-T with TPS and ArcCHECK®-3DVH® along with ArcCHECK®-3DVH® versus TPS dose matrixes were performed with the aid of the polyGeVero® by analyzing dose profiles, isodoses lines, gamma index, gamma angle, dose difference, and related histograms. RESULTS The measured MR-relaxation rate (R2 = 1/T2) for the dosimeters relates to the dose, as follows: R2 = 0.0928 ± 0.0008 [Gy-1 s-1] × D [Gy] + 2.985 ± 0.012 [s-1] (VIC) and 0.1839 ± 0.0044 [Gy-1 s-1] × D [Gy] + 2.519 ± 0.053 [s-1] (VIC-T). The 3D-to-3D comparisons revealed a good agreement between the measured and calculated 3D dose distributions. CONCLUSIONS VIC and VIC-T with 3T MRI readout and polyGeVero® showed potential for verifications of calculated irradiation plans. The results obtained suggest the implementation of the irradiation plan for eradication of the lung tumour.
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Kouvati K, Jaszczak M, Papagiannis P, Kadlubowski S, Wach R, Maras P, Dudek M, Kozicki M. Leuco crystal violet-Pluronic F-127 3D radiochromic gel dosimeter. ACTA ACUST UNITED AC 2019; 64:175017. [DOI: 10.1088/1361-6560/ab2f5d] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Vieira SL, de Oliveira LN, Carneiro AAO. Quantitative magnetic resonance elastography for polymer-gel dosimetry phantoms. Med Eng Phys 2019; 66:102-106. [PMID: 30846236 DOI: 10.1016/j.medengphy.2019.02.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 12/03/2018] [Accepted: 02/10/2019] [Indexed: 01/17/2023]
Abstract
Commonly dose-responses of conventional dosimetric methods are affected by a saturation dose and are known to be limited when the delivered dose is relatively high. In contrast, elastic properties of polymer-gel dosimeter phantoms play major roles in a new dosimetry technique using magnetic resonance elastography (MRE). A single volume of polymer-gel dosimeter solution containing methacrylic and ascorbic acid in gelatin initiated by copper was prepared. The material was subsequently stored in cylindrical containers for future use as a biological tissue-mimicking phantom material. The phantom material was irradiated with gamma rays, where absorbed doses of 10-50 Gy were delivered. To study the dynamic elastic behaviour, periodic mechanical external forces of 100-400 Hz were applied to generate shear waves in the samples. The radiation-induced changes in the shear modulus of the samples were estimated from wave-displacement images and converted to elastograms. The smallest and largest shear modulus values were approximately 2.10 ± 0.64 and 35.26 ± 2.85 kPa, respectively. The dynamic elastic response of the polymer-gel dosimeters showed an increased dependency with frequency. A linear relationship (R2 = 0.996) was observed between the integrated area and the absorbed dose of the samples. The elastograms clearly showed that the largest shear modulus values were in the irradiated region of the polymer-gel dosimeter phantoms. Quantitative values of the shear modulus of polymer-gel dosimeters were estimated using MRE.
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Affiliation(s)
- Sílvio Leão Vieira
- Instituto de Física, Universidade Federal de Goiás - UFG, Goiás, Brazil.
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Tiago MM, Higuti RT, Segura LE, Kitano C, Assuncao E, Oliveira SL. Versatile Ultrasonic Spectrometer for Liquids With Practical Sample Handling by Using Standard Cuvettes. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2019; 66:109-118. [PMID: 30334755 DOI: 10.1109/tuffc.2018.2875872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This work describes the development and tests of a new ultrasonic spectrometer for liquids based on the use of commercial cuvettes for sample handling. The spectrometer operates in the frequency range from 20 to 80 MHz and gathers some important characteristics, which are its high thermal stability (better than 0.01 °C), by the use of Peltier cells, and practical sample handling with small volume (≤3 ml) samples placed inside cuvettes which can be easily removed from the spectrometer, cleaned/sterilized, or simply discarded. Through-transmission operation is used to measure propagation velocity and attenuation coefficient, and the spectrometer was tested with mixtures of water and NaCl, which have attenuations smaller than that of distilled water, and higher attenuation samples of silicone and castor oil. Backscattering studies of polystyrene particles of 10- and 15- [Formula: see text] diameters were also conducted, showing the versatility of the instrument.
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Farhood B, Geraily G, Abtahi SMM. A systematic review of clinical applications of polymer gel dosimeters in radiotherapy. Appl Radiat Isot 2019; 143:47-59. [PMID: 30390500 DOI: 10.1016/j.apradiso.2018.08.018] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 12/15/2022]
Abstract
Radiotherapy has rapidly improved because of the use of new equipment and techniques. Hence, the appeal for a feasible and accurate three-dimensional (3D) dosimetry system has increased. In this regard, gel dosimetry systems are accurate 3D dosimeters with high resolution. This systematic review evaluates the clinical applications of polymer gel dosimeters in radiotherapy. To find the clinical applications of polymer gel dosimeters in radiotherapy, a full systematic literature search was performed on the basis of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in electronic databases up to January 31, 2017, with use of search-related terms in the titles and abstracts of articles. A total of 765 articles were screened in accordance with our inclusion and exclusion criteria. Eventually, 53 articles were included in the study. The findings show that most clinical applications of polymer gel dosimeters relate to external radiotherapy. Most of the gel dosimeters studied have acceptable dose accuracy as a 3D dosimeter with high resolution. It is difficult to judge which is the best polymer gel dosimeter to use in a clinical setting, because each gel dosimeter has advantages and limitations. For example, methacrylic acid-based gel dosimeters have high dose sensitivity and low toxicity, while their dose response is beam energy dependent; in contrast, N-isopropylacrylamide gel dosimeters have low dose resolution, but their sensitivity is lower and they are relatively toxic.
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Affiliation(s)
- Bagher Farhood
- Department of Medical Physics and Radiology, Faculty of Paramedical Sciences, Kashan University of Medical Sciences, 8115187159 Kashan, Iran
| | - Ghazale Geraily
- Medical Physics and Medical Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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Abtahi SMM, Pourghanbari M. A new less toxic polymer gel dosimeter: Radiological characteristics and dosimetry properties. Phys Med 2018; 53:137-144. [PMID: 30241748 DOI: 10.1016/j.ejmp.2018.08.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/20/2018] [Accepted: 08/25/2018] [Indexed: 12/27/2022] Open
Abstract
PURPOSE A new polymer gel dosimeter recipe was investigated that may be more suitable for widespread applications than polyacrylamide gel dosimeters, since the extremely toxic acrylamide has been replaced with the less harmful monomer 2-Acrylamido 2-Methyl Propane Sulfonic acid (AMPS). METHODS The new formulation was named PAMPSGAT. The MRI response (R2) of the dosimeters was analyzed for conditions of varying dose, dose rate, and temperature during scanning. Radiological properties of the PAMPSGAT polymer gel dosimeter were investigated. RESULTS The dose-response (R2) of AMPS/Bis appears to be linear over a dose range 10-40 Gy. The percentage of difference between the R2 values for imaging at 15 °C and MRI room temperature is about 4.6% for vial with 40 Gy absorbed dose which decreased to less than 1% for imaging at 20 °C. The percentage difference of Zeff of PAMPSGAT gel and soft tissue was less than 1% in the practical energy range (100 KeV-100 MeV). The electron density of the PAMPSGAT polymer gel was 2.9% higher than that of muscle. Results showed that the sensitivity of PAMPSGAT polymer gel dosimeter irradiated by 60Co (energy = 1.25 MeV) is about 27.7% higher than that of irradiated using a 6 MeV Linac system. CONCLUSIONS Temperature during MRI scanning has a small effect on the R2 response of the PAMPSGAT polymer gel dosimeter. Results confirmed tissue equivalency of the PAMPSGAT polymer gel dosimeter in most practical energy range. The PAMPSGAT polymer gel dosimeter response depends on energy and dose rate.
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Affiliation(s)
| | - Mohammad Pourghanbari
- Medical Imaging Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Sathiyaraj P, Samuel EJ. Feasibility study of basic characterization of MAGAT polymer gel using CBCT attached in linear accelerator: Preliminary study. Radiat Phys Chem Oxf Engl 1993 2018. [DOI: 10.1016/j.radphyschem.2017.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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Abtahi SMM, Sadeghi Abandansari H. Polymer gel dosimeters with PVA-GA matrix. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2017; 40:651-658. [PMID: 28752320 DOI: 10.1007/s13246-017-0573-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 07/19/2017] [Indexed: 11/29/2022]
Abstract
Properties of a new polymer gel with cross-linked polyvinyl alcohol as a gelatinous matrix were investigated. The new polymer gel dosimeter was named PVABAT. The irradiation was performed using a calibrated 60Co beam. The dose responses of the PVABAT formulations were quantified with MRI transverse relaxation rate (R2) measurements. The results show that the PVABAT gel responds linearly to the absorbed dose for doses from 30 up to 45 Gy. The maximal amount of [Formula: see text] of PVABAT polymer gel dosimeter was about 0.19 Gy which was indicated on a better resolution in comparison with previously reported acrylamide-based polymer gel dosimeters formulations. Furthermore, the gel response remains stable in the investigated time (192 h) after the irradiation. The effective atomic number and electron density of the new gel showed a maximum difference of 3.2 and 2% with soft tissue respectively. The melting point also increased significantly for new formulation. Furthermore, the new gel formulation has an elemental tissue equivalency for dosimetry applications involving nuclear reactions.
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Affiliation(s)
- Seyed Mohammad Mahdi Abtahi
- Department of Physics, Imam Khomeini International University, Norouzian, P. O. Box 34149-16818, Qazvin, Iran.
| | - Hamid Sadeghi Abandansari
- Department of cell Engineering, Cell Sience Research Center, Royan Institute for Stem cell Biology and Technology, Tehran, Iran
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Kozicki M, Kwiatos K, Kadlubowski S, Dudek M. TTC-Pluronic 3D radiochromic gel dosimetry of ionizing radiation. ACTA ACUST UNITED AC 2017; 62:5668-5690. [DOI: 10.1088/1361-6560/aa77eb] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Kakakhel MB, Jirasek A, Johnston H, Kairn T, Trapp JV. Improving the quality of reconstructed X-ray CT images of polymer gel dosimeters: zero-scan coupled with adaptive mean filtering. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2017; 40:159-165. [PMID: 28168587 DOI: 10.1007/s13246-017-0523-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/12/2017] [Indexed: 11/25/2022]
Abstract
This study evaluated the feasibility of combining the 'zero-scan' (ZS) X-ray computed tomography (CT) based polymer gel dosimeter (PGD) readout with adaptive mean (AM) filtering for improving the signal to noise ratio (SNR), and to compare these results with available average scan (AS) X-ray CT readout techniques. NIPAM PGD were manufactured, irradiated with 6 MV photons, CT imaged and processed in Matlab. AM filter for two iterations, with 3 × 3 and 5 × 5 pixels (kernel size), was used in two scenarios (a) the CT images were subjected to AM filtering (pre-processing) and these were further employed to generate AS and ZS gel images, and (b) the AS and ZS images were first reconstructed from the CT images and then AM filtering was carried out (post-processing). SNR was computed in an ROI of 30 × 30 for different pre and post processing cases. Results showed that the ZS technique combined with AM filtering resulted in improved SNR. Using the previously-recommended 25 images for reconstruction the ZS pre-processed protocol can give an increase of 44% and 80% in SNR for 3 × 3 and 5 × 5 kernel sizes respectively. However, post processing using both techniques and filter sizes introduced blur and a reduction in the spatial resolution. Based on this work, it is possible to recommend that the ZS method may be combined with pre-processed AM filtering using appropriate kernel size, to produce a large increase in the SNR of the reconstructed PGD images.
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Affiliation(s)
- M B Kakakhel
- Department of Physics and Applied Mathematics (DPAM), Pakistan Institute of Engineering and Applied Sciences, Nilore, 45450, Islamabad, Pakistan
| | - A Jirasek
- I.K. Barber School of Arts and Science, University of British Columbia, Okanagan Campus, Vancouver, BC, Canada
| | - H Johnston
- Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - T Kairn
- Genesis Cancer Care Queensland, Brisbane, QLD, Australia.
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD, Australia.
| | - J V Trapp
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD, Australia
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Kozicki M, Jaszczak M, Maras P, Dudek M, Cłapa M. On the development of a VIPARndradiotherapy 3D polymer gel dosimeter. Phys Med Biol 2017; 62:986-1008. [DOI: 10.1088/1361-6560/aa5089] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Abtahi S. Characteristics of a novel polymer gel dosimeter formula for MRI scanning: Dosimetry, toxicity and temporal stability of response. Phys Med 2016; 32:1156-61. [DOI: 10.1016/j.ejmp.2016.08.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 07/17/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022] Open
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23
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O'Shea T, Bamber J, Fontanarosa D, van der Meer S, Verhaegen F, Harris E. Review of ultrasound image guidance in external beam radiotherapy part II: intra-fraction motion management and novel applications. Phys Med Biol 2016; 61:R90-137. [PMID: 27002558 DOI: 10.1088/0031-9155/61/8/r90] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Imaging has become an essential tool in modern radiotherapy (RT), being used to plan dose delivery prior to treatment and verify target position before and during treatment. Ultrasound (US) imaging is cost-effective in providing excellent contrast at high resolution for depicting soft tissue targets apart from those shielded by the lungs or cranium. As a result, it is increasingly used in RT setup verification for the measurement of inter-fraction motion, the subject of Part I of this review (Fontanarosa et al 2015 Phys. Med. Biol. 60 R77-114). The combination of rapid imaging and zero ionising radiation dose makes US highly suitable for estimating intra-fraction motion. The current paper (Part II of the review) covers this topic. The basic technology for US motion estimation, and its current clinical application to the prostate, is described here, along with recent developments in robust motion-estimation algorithms, and three dimensional (3D) imaging. Together, these are likely to drive an increase in the number of future clinical studies and the range of cancer sites in which US motion management is applied. Also reviewed are selections of existing and proposed novel applications of US imaging to RT. These are driven by exciting developments in structural, functional and molecular US imaging and analytical techniques such as backscatter tissue analysis, elastography, photoacoustography, contrast-specific imaging, dynamic contrast analysis, microvascular and super-resolution imaging, and targeted microbubbles. Such techniques show promise for predicting and measuring the outcome of RT, quantifying normal tissue toxicity, improving tumour definition and defining a biological target volume that describes radiation sensitive regions of the tumour. US offers easy, low cost and efficient integration of these techniques into the RT workflow. US contrast technology also has potential to be used actively to assist RT by manipulating the tumour cell environment and by improving the delivery of radiosensitising agents. Finally, US imaging offers various ways to measure dose in 3D. If technical problems can be overcome, these hold potential for wide-dissemination of cost-effective pre-treatment dose verification and in vivo dose monitoring methods. It is concluded that US imaging could eventually contribute to all aspects of the RT workflow.
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Affiliation(s)
- Tuathan O'Shea
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, London SM2 5NG, UK
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24
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Masoumi H, Mokhtari-Dizaji M, Arbabi A, Bakhshandeh M. Determine the Dose Distribution Using Ultrasound Parameters in MAGIC-f Polymer Gels. Dose Response 2016; 14:1559325815625647. [PMID: 26924952 PMCID: PMC4753354 DOI: 10.1177/1559325815625647] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this study, using methacrylic and ascorbic acid in gelatin initiated by copper (MAGIC-f) polymer gel after megavoltage energy exposure, the sensitivity of the ultrasound velocity and attenuation coefficient dose-dependent parameters was evaluated. The MAGIC-f polymer gel was irradiated under 1.25 MeV cobalt-60, ranging from 0 to 60 Gy in 2-Gy steps, and received dose uniformity and accuracy of ±2%. After calibration of the ultrasonic systems with a frequency of 500 kHz, the parameters of ultrasound velocity and attenuation coefficient of the irradiated gel samples were measured. According to the dose-response curve, the ability of ultrasonic parameters was evaluated in dose rate readings. Based on a 4-order polynomial curve, fitted on the dose-response parameters of ultrasound velocity and attenuation coefficient and observed at 24 hours after irradiation, ultrasonic parameters had more sensitivity. The sensitivity of the dose-velocity and dose-attenuation coefficient curves was observed as 50 m/s/Gy and 0.06 dB/MHz/Gy over the linear range of 4 to 44 Gy, respectively. The ultrasonic parameters at 5°C, 15°C, and 25°C on the gel dosimeter after 0 to 60 Gy irradiation showed that readings at 25°C have higher sensitivity compared to 15°C and 5°C. Maximum sensitivity time and temperature readings of the MAGIC-f ultrasonic parameters were concluded 24 hours after irradiation and at a temperature of 25°C.
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Affiliation(s)
- Hossein Masoumi
- Medical Physics Department, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Manijhe Mokhtari-Dizaji
- Medical Physics Department, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Azim Arbabi
- Radiotherapy and Oncology Department, Faculty of Medical Sciences, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran
| | - Mohsen Bakhshandeh
- Radiology Technology Department, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran
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25
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The feasibility assessment of radiation dose of movement 3D NIPAM gel by magnetic resonance imaging. Radiat Phys Chem Oxf Engl 1993 2015. [DOI: 10.1016/j.radphyschem.2015.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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26
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Mattea F, Chacón D, Vedelago J, Valente M, Strumia MC. Polymer gel dosimeter based on itaconic acid. Appl Radiat Isot 2015; 105:98-104. [PMID: 26275817 DOI: 10.1016/j.apradiso.2015.07.042] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/25/2015] [Indexed: 12/21/2022]
Abstract
A new polymeric dosimeter based on itaconic acid and N, N'-methylenebisacrylamide was studied. The preparation method, compositions of monomer and crosslinking agent and the presence of oxygen in the dosimetric system were analyzed. The resulting materials were irradiated with an X-ray tube at 158cGy/min, 226cGymin and 298cGy/min with doses up to 1000Gy. The dosimeters presented a linear response in the dose range 75-1000Gy, sensitivities of 0.037 1/Gyat 298cGy/min and an increase in the sensitivity with lower dose rates. One of the most relevant outcomes in this study was obtaining different monomer to crosslinker inclusion in the formed gel for the dosimeters where oxygen was purged during the preparation method. This effect has not been reported in other typical dosimeters and could be attributed to the large differences in the reactivity among these species.
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Affiliation(s)
- Facundo Mattea
- Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, CONICET, Córdoba, Argentina; Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIR(X)) - Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina.
| | - David Chacón
- Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIR(X)) - Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Física, Universidad Nacional, Heredia, Costa Rica
| | - José Vedelago
- Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIR(X)) - Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina; Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina; Instituto de Física Enrique Gaviola, CONICET, Córdoba, Argentina; Instituto de Física Enrique Gaviola, CONICET, Córdoba, Argentina
| | - Mauro Valente
- Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIR(X)) - Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina; Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba, Córdoba, Argentina; Instituto de Física Enrique Gaviola, CONICET, Córdoba, Argentina; Instituto de Física Enrique Gaviola, CONICET, Córdoba, Argentina
| | - Miriam C Strumia
- Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina; Instituto Multidisciplinario de Biología Vegetal, CONICET, Argentina
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27
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Effect of light source instability on uniformity of 3D reconstructions from a cone beam optical CT scanner. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2014; 37:791-8. [PMID: 25262165 DOI: 10.1007/s13246-014-0302-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 09/19/2014] [Indexed: 01/01/2023]
Abstract
Temporally varying light intensity during acquisition of projection images in an optical CT scanner can potentially be misinterpreted as physical properties of the sample. This work investigated the impact of LED light source intensity instability on measured attenuation coefficients. Different scenarios were investigated by conducting one or both of the reference and data scans in a 'cold' scanner, where the light source intensity had not yet stabilised. Uniform samples were scanned to assess the impact on measured uniformity. The orange (590 nm) light source decreased in intensity by 29 % over the first 2 h, while the red (633 nm) decreased by 9 %. The rates of change of intensity at 2 h were 0.1 and 0.03 % respectively over a 5 min period-corresponding to the scan duration. The normalisation function of the reconstruction software does not fully account for the intensity differences and discrepancies remain. Attenuation coefficient inaccuracies of up to 8 % were observed for data reconstructed from projection images acquired with a cold scanner. Increased noise was observed for most cases where one or both of the scans was acquired without sufficient warm-up. The decrease in accuracy and increase in noise were most apparent for data reconstructed from reference and data scans acquired with a cold scanner on different days.
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28
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Khoei S, Trapp JV, Langton CM. Ultrasound attenuation computed tomography assessment of PAGAT gel dose. Phys Med Biol 2014; 59:N129-37. [PMID: 25049236 DOI: 10.1088/0031-9155/59/15/n129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Ultrasound has been previously investigated as an alternative readout method for irradiated polymer gel dosimeters, with authors reporting varying dose responses. We extend previous work utilizing a new computed tomography ultrasound scanner comprising of two identical 5 MHz, 128-element linear-array ultrasound transducers, co-axially aligned and submerged in water as a coupling agent, with rotational of the gel dosimeter between the transducers facilitated by a robotic arm. We have investigated the dose-dependence of both ultrasound bulk attenuation and broadband ultrasound attenuation (BUA) for the PAGAT gel dosimeter. The ultrasound bulk attenuation dose sensitivity was found to be 1.46 ± 0.04 dB m( -1) Gy( -1), being in agreement with previously published results for PAG and MAGIC gels. BUA was also found to be dose dependent and was measured to be 0.024 ± 0.003 dB MHz( -1) Gy( -1); the advantage of BUA being its insensitivity to frequency-independent attenuation mechanisms including reflection and refraction, thereby minimizing image reconstruction artefacts.
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Affiliation(s)
- S Khoei
- School of Chemistry, Physics, & Mechanical Engineering, Institute of Health & Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Australia
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29
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Kozicki M, Maras P, Karwowski AC. Software for 3D radiotherapy dosimetry. Validation. Phys Med Biol 2014; 59:4111-36. [DOI: 10.1088/0031-9155/59/15/4111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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30
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Abtahi SM, Aghamiri SMR, Khalafi H. Optical and MRI investigations of an optimized acrylamide-based polymer gel dosimeter. J Radioanal Nucl Chem 2014. [DOI: 10.1007/s10967-014-2983-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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31
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Farrugia M, Morgan SP, Alexander C, Mather ML. Ultrasonic monitoring of drug loaded Pluronic F127 micellular hydrogel phase behaviour. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 34:280-6. [DOI: 10.1016/j.msec.2013.09.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 08/04/2013] [Accepted: 09/18/2013] [Indexed: 11/15/2022]
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32
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Kawamura H, Shinoda K, Miyamoto K, Sakae T, Monma M, Matsumura A. [Investigation of polymer gel dosimetry for small circular irradiated fields]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2013; 69:933-943. [PMID: 24064697 DOI: 10.6009/jjrt.2013_jsrt_69.9.933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Polymer gels can be used as tissue equivalent dosimeters, and polymer gel dosimetry can be employed without perturbation of the radiation field. In this study, polymer gel dosimetry was used for small circular irradiation fields 10-30 mm in diameter using a radiation planning system. The irradiated gels were compared with planned data for a 50% dose width of 6 Gy dose maximum, and for the dose difference between gels and planned data over an 80% dose maximum area. The present study investigated magnetic resonance imaging (MRI) conditions based on an optimal dose-R2 calibration curve. The average difference between the full width half maximum of the 50% dose width between gels and planned data was 11%. The average dose difference over 80% of the dose was 5.6%. Optimal dose-R2 calibration curves were acquired using images with echo times of 30 and 60 ms. For cases of larger thicknesses and an increasing number of averages, the coefficients of variance of the curves were smaller than under other conditions. Compared to other traditional dosimetric tools, polymer gels have the advantage of providing three-dimensional dosimetric data. An arbitrary profile from the gel's data can be compared with the profile of the planned data. In the future, new gel dosimeters will be needed that demonstrate improved dose evaluation under 1 Gy and stability in high dose areas.
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Affiliation(s)
- Hiraku Kawamura
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences
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33
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Shih CT, Hsu JT, Han RP, Hsieh BT, Chang SJ, Wu J. A novel method of estimating dose responses for polymer gels using texture analysis of scanning electron microscopy images. PLoS One 2013; 8:e67281. [PMID: 23843998 PMCID: PMC3699568 DOI: 10.1371/journal.pone.0067281] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/16/2013] [Indexed: 12/20/2022] Open
Abstract
Polymer gels are regarded as a potential dosimeter for independent validation of absorbed doses in clinical radiotherapy. Several imaging modalities have been used to convert radiation-induced polymerization to absorbed doses from a macro-scale viewpoint. This study developed a novel dose conversion mechanism by texture analysis of scanning electron microscopy (SEM) images. The modified N-isopropyl-acrylamide (NIPAM) gels were prepared under normoxic conditions, and were administered radiation doses from 5 to 20 Gy. After freeze drying, the gel samples were sliced for SEM scanning with 50×, 500×, and 3500× magnifications. Four texture indices were calculated based on the gray level co-occurrence matrix (GLCM). The results showed that entropy and homogeneity were more suitable than contrast and energy as dose indices for higher linearity and sensitivity of the dose response curves. After parameter optimization, an R2 value of 0.993 can be achieved for homogeneity using 500× magnified SEM images with 27 pixel offsets and no outlier exclusion. For dose verification, the percentage errors between the prescribed dose and the measured dose for 5, 10, 15, and 20 Gy were −7.60%, 5.80%, 2.53%, and −0.95%, respectively. We conclude that texture analysis can be applied to the SEM images of gel dosimeters to accurately convert micro-scale structural features to absorbed doses. The proposed method may extend the feasibility of applying gel dosimeters in the fields of diagnostic radiology and radiation protection.
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Affiliation(s)
- Cheng-Ting Shih
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan, R.O.C
| | - Jui-Ting Hsu
- School of Dentistry, China Medical University, Taichung, Taiwan, R.O.C
| | - Rou-Ping Han
- Department of Management Information Systems, Central Taiwan University of Science and Technology, Taichung, Taiwan, R.O.C
| | - Bor-Tsung Hsieh
- Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan, R.O.C
| | - Shu-Jun Chang
- Health Physics Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan, R.O.C
| | - Jay Wu
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan, R.O.C
- * E-mail:
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34
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Hiroki A, Yamashita S, Sato Y, Nagasawa N, Taguchi M. New polymer gel dosimeters consisting of less toxic monomers with radiation-crosslinked gel matrix. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/444/1/012028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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35
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Gorjiara T, Kacperek A, Kuncic Z, Baldock C, Doran S. Preliminary characterization of PRESAGE®for 3D dosimetry of 62 MeV proton beam. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/444/1/012058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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36
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Chiang CM, Hsieh BT, Shieh JI, Cheng KY, Hsieh LL. An approach in exploring the fundamental dosimetric characteristics for a long shelf life irradiated acrylamide-based gel. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-013-2564-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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37
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An evaluation of dosimetric characteristics of MAGIC gel modified by adding formaldehyde (MAGIC-f). RADIAT MEAS 2012. [DOI: 10.1016/j.radmeas.2012.10.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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38
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Johnston H, Hilts M, Carrick J, Jirasek A. An x-ray CT polymer gel dosimetry prototype: II. Gel characterization and clinical application. Phys Med Biol 2012; 57:3155-75. [DOI: 10.1088/0031-9155/57/10/3155] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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39
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Pavoni JF, Pike TL, Snow J, DeWerd L, Baffa O. Tomotherapy dose distribution verification using MAGIC-fpolymer gel dosimetry. Med Phys 2012; 39:2877-84. [DOI: 10.1118/1.4704496] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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40
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Hsieh LL, Cheng KY, Hsieh BT. A novel thin NIPAM gel cassette dosimeter for photon-beam radiotherapy. PLoS One 2012; 7:e31836. [PMID: 22427810 PMCID: PMC3299645 DOI: 10.1371/journal.pone.0031836] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 01/12/2012] [Indexed: 11/18/2022] Open
Abstract
The response of thin polymer gel cassettes (called NIPAM gels) to ionizing radiation was investigated in this study. The NIPAM gels were prepared from gelatin, N-isopropyl acrylamide, tetrakis (hydroxymethyl) phosphoniumchloride, and N,N′-methylene-bis-acrylamide. Gel cassettes were irradiated in a phantom using a linear accelerator, and the polymerization morphology of irradiated NIPAM gel was characterized using scanning electron microscopy. The dose-response sensitivity of the NIPAM gels was evaluated using the differences in optical densities. The optical densities were obtained using a computer-controlled CCD camera that was connected to a planar illumination source for acquisition of optical transmission images. The central axis depth dose profiles of the phantom were extracted, and a comparison with ionization chamber measurements demonstrated similarities in profiles. The sensitivity, linearity of the response, accuracy, and reproducibility of the polymer gel cassettes were acceptable. However, the profiles of the half-blocked field irradiation showed no significant dispersion in the visible region. This study also extensively investigated the spatial stability of the NIPAM gel. The results showed that the gel cassette response remains stable for up to three months after irradiation.
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Affiliation(s)
- Ling-Ling Hsieh
- Department of Medical Imaging and Radiological Sciences, Central Taiwan University of Science and Technology, Beitun District, Taichung City, Taiwan, Republic of China.
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41
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Kakakhel MB, Kairn T, Kenny J, Trapp JV. Improved image quality for x-ray CT imaging of gel dosimeters. Med Phys 2011; 38:5130-5. [DOI: 10.1118/1.3626487] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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42
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43
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Baldock C, De Deene Y, Doran S, Ibbott G, Jirasek A, Lepage M, McAuley KB, Oldham M, Schreiner LJ. Polymer gel dosimetry. Phys Med Biol 2010. [PMID: 20150687 DOI: 10.1088/0031‐9155/55/5/r01] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented.
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Affiliation(s)
- C Baldock
- Institute of Medical Physics, School of Physics, University of Sydney, Australia.
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44
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Baldock C, De Deene Y, Doran S, Ibbott G, Jirasek A, Lepage M, McAuley KB, Oldham M, Schreiner LJ. Polymer gel dosimetry. Phys Med Biol 2010; 55:R1-63. [PMID: 20150687 DOI: 10.1088/0031-9155/55/5/r01] [Citation(s) in RCA: 450] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented.
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Affiliation(s)
- C Baldock
- Institute of Medical Physics, School of Physics, University of Sydney, Australia.
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45
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Sellakumar P, James Jebaseelan Samuel E. Study on energy dependence of PAGAT polymer gel dosimeter evaluated using X-Ray CT. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2009.11.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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46
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Lin MH, Huang TC, Kao MJ, Wu J, Chen CL, Wu TH. Three-dimensional dosimetry in brachytherapy: A MAGAT study. Appl Radiat Isot 2009; 67:1432-7. [PMID: 19303785 DOI: 10.1016/j.apradiso.2009.02.072] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study is to evaluate the influence of using different matrix size of smoothing filter for image post-processing and various slice thickness during MR imaging on dose estimation in Ir-192 HDR brachytherapy via normoxic polymer gel dosimeter. Our results show its sensitive nature in gel dosimeter while changing these parameters, among which the combination of 2mm slice thickness of MR images and [5x5] smoothing filter are considered the optimal parameters to provide accurate dose estimations and isodose curves.
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Affiliation(s)
- Min-Hsing Lin
- Department of Family Medicine and Physical Check-up Center, Tainan Hospital Department of Health, Executive Yuan, Taiwan, ROC
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47
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Sakhalkar HS, Oldham M. Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation. Med Phys 2008; 35:101-11. [PMID: 18293567 DOI: 10.1118/1.2804616] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of approximately 5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes artifacts from scattered and stray-light sources, and (iii) high resolution (potentially 50 microm) isotropic 3D dose readout. The performance of the CCD scanner for 3D dose readout was evaluated by comparison with independent 3D readout from the single laser beam OCTOPUS-scanner for the same PRESAGE dosimeters. The OCTOPUS scanner was considered the "gold standard" technique in light of prior studies demonstrating its accuracy. Additional comparisons were made against calculated dose distributions from the ECLIPSE treatment-planning system. Dose readout for the following treatments were investigated: (i) a single rectangular beam irradiation to investigate small field and very steep dose gradient dosimetry away from edge effects, (ii) a 2-field open beam parallel-opposed irradiation to investigate dosimetry along steep dose gradients, and (iii) a 7-field intensity modulated radiation therapy (IMRT) irradiation to investigate dosimetry for complex treatment delivery involving modulation of fluence and for dosimetry along moderate dose gradients. Dose profiles, dose-difference plots, and gamma maps were employed to evaluate quantitative estimates of agreement between independently measured and calculated dose distributions. Results indicated that dose readout from the CCD scanner was in agreement with independent gold-standard readout from the OCTOPUS-scanner as well as the calculated ECLIPSE dose distribution for all treatments, except in regions within a few millimeters of the edge of the dosimeter, where edge artifact is predominant. Agreement of line profiles was observed, even along steep dose gradients. Dose difference plots indicated that the CCD scanner dose readout differed from the OCTOPUS scanner readout and ECLIPSE calculations by approximately 10% along steep dose gradients and by approximately 5% along moderate dose gradients. Gamma maps (3% dose-difference and 3 mm distance-to-agreement acceptance criteria) revealed agreement, except for regions within 5 mm of the edge of the dosimeter where the edge artifact occurs. In summary, the data demonstrate feasibility of using the fast, high-resolution CCD scanner for comprehensive 3D dosimetry in all applications, except where dose readout is required close to the edges of the dosimeter. Further work is ongoing to reduce this artifact.
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Affiliation(s)
- H S Sakhalkar
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA.
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Hill B, Venning AJ, Baldock C. Polymer gel dosimetry on a multislice computed tomography scanner: effect of changing parameters on CTDI. Phys Med 2008; 24:149-58. [PMID: 18289906 DOI: 10.1016/j.ejmp.2007.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Revised: 11/20/2007] [Accepted: 11/22/2007] [Indexed: 11/15/2022] Open
Abstract
Polymer gel dosimetry undertaken on a multislice CT scanner provides an alternative method to conventional dosimetry measurements. Polymer gel dosimeters were used to measure CT radiation doses and compared to TLD and ionization chamber measurements in different diameter phantoms. CTDI was investigated for each of these phantoms for a range of mAs (100-400 mAs), tube voltage (100-135 kV) and nominal slice width (2-32 mm). Linear fits of the CTDI values for mAs show for the smallest phantom diameter an increase in CTDI of 60% for both TLD and polymer gel dosimeters. A similar increase in CTDI of 50% at 100 kVp and 100% for 135 kVp was also noted. It was also shown that slice width variation measured with either polymer gel or TLD was greatest with the smallest slice widths. In summary, it was found that polymer gels can be used as an alternative dosimeter to TLD for the determination of SWDP and subsequent CTDI calculations.
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Affiliation(s)
- B Hill
- Medical Physics, The Canberra Hospital, ACT Health, Woden, Canberra, ACT 2606, Australia.
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Baldock C. Historical overview of the development of gel dosimetry: a personal perspective. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1742-6596/56/1/002] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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