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Fuse H, Oyama S, Yasue K, Ito S, Sato T, Fujisaki T, Abe S, Oyama K, Suzuki A, Yoshizawa T, Kitajima Y. Design and characteristics of an agar additive polymer gel dosimeter. Appl Radiat Isot 2019; 151:62-66. [PMID: 31158707 DOI: 10.1016/j.apradiso.2019.04.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 04/16/2019] [Accepted: 04/30/2019] [Indexed: 10/26/2022]
Abstract
Herein, we investigate the use of agar and gelatin in a polymer gel dosimeter. The polymer gel is enclosed in a vinyl film to obtain a dosimeter of arbitrary shape and maintain the shape at room temperature. The resulting polymer gel dosimeter could preserve its shape across a wide temperature range. Excluding the surface region, the obtained dose distribution was within 3% of that determined in an ionization chamber.
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Affiliation(s)
- Hiraku Fuse
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan.
| | - Satoshi Oyama
- Graduate School of Health Sciences, Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Kenji Yasue
- Graduate School of Health Sciences, Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Shotaro Ito
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Tomoaki Sato
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Tatsuya Fujisaki
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Shinji Abe
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami-machi, Inashiki-gun, Ibaraki, 300-3094, Japan
| | - Katsuhiko Oyama
- Department of Radiation Therapy, Tsuchiura Kyodo General Hospital, 4-1-1, Ootsuno, Tsuchiura-city, Ibaraki, 300-0028, Japan
| | - Akiyoshi Suzuki
- Department of Radiation Therapy, Tsuchiura Kyodo General Hospital, 4-1-1, Ootsuno, Tsuchiura-city, Ibaraki, 300-0028, Japan
| | - Tomoyuki Yoshizawa
- Department of Radiation Therapy, Tsuchiura Kyodo General Hospital, 4-1-1, Ootsuno, Tsuchiura-city, Ibaraki, 300-0028, Japan
| | - Yuiko Kitajima
- Department of Radiation Therapy, Tsuchiura Kyodo General Hospital, 4-1-1, Ootsuno, Tsuchiura-city, Ibaraki, 300-0028, Japan
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Vedelago J, Quiroga A, Triviño S, Mattea F, Valente M. Parameter estimation and mathematical modeling of the diffusion process of a benzoic acid infused Fricke gel dosimeter. Appl Radiat Isot 2019; 151:89-95. [PMID: 31158711 DOI: 10.1016/j.apradiso.2019.04.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 04/23/2019] [Accepted: 04/29/2019] [Indexed: 10/26/2022]
Abstract
This work presents a mathematical model implementation for studying the diffusion process of ferric ions in post-irradiated Fricke gel dosimeters. Fricke gel samples were manufactured in layers for their analysis by optical transmission imaging and benzoic acid was incorporated to improve their radiosensitivity. The developed method consists on designing the dosimeters with a suitable composition for their optical analysis which allows accurate measurements in a wide dose range with noticeable linear responses with an average linear correlation coefficient of r2=0.993. The developed algorithm calculates the diffusion coefficient by means of an inverse problem formulation. Moreover, the proposed method is capable of modeling time-dependent physical properties and evolution over time of the irradiated dosimeters accurately and comparable with experimentally measured data. The obtained results evince the complexity of the diffusion phenomena in this type of materials and the capacity of the proposed method to provide a reliable quantification of the diffusion coefficient as a scalar approximation of the diffusion tensor. The obtained diffusion coefficient varies from 1.21 to 1.61 mm2/h with uncertainties lower than 2%. The model is also transferable to other diffusion driven systems and the numerical solving method can also be adapted to solve diffusion calculation based on other theoretical approaches.
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Affiliation(s)
- José Vedelago
- Instituto de Física Enrique Gaviola (IFEG), CONICET, Córdoba, Argentina; Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIRx), FAMAF-UNC, Córdoba, Argentina.
| | - Andrés Quiroga
- Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIRx), FAMAF-UNC, Córdoba, Argentina; Departamento de Matemática, CRUB-UNCo, Río Negro, Argentina
| | - Sebastián Triviño
- Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIRx), FAMAF-UNC, Córdoba, Argentina; Centro Atómico Ezeiza (CAE), Comisión Nacional de Energía Atómica (CNEA), Buenos Aires, Argentina
| | - Facundo Mattea
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Orgánica, Córdoba, Argentina; Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA), CONICET, Córdoba, Argentina; Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIRx), FAMAF-UNC, Córdoba, Argentina
| | - Mauro Valente
- Instituto de Física Enrique Gaviola (IFEG), CONICET, Córdoba, Argentina; Laboratorio de Investigación e Instrumentación en Física Aplicada a la Medicina e Imágenes por Rayos X (LIIFAMIRx), FAMAF-UNC, Córdoba, Argentina; Centro de Física e Ingeniería en Medicina - CFIM & Departamento de Ciencias Físicas, Universidad de La Frontera, Temuco, Chile.
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Bleuse O, Gschwind R, Bailly Y, Laurent K, Bártová H, Pilařová K, Spěváček V, Makovicka L. 3D Dosimetry based on a new optical approach for dosimetry gels: Use of the polarisation ratio of the scattering light. ACTA ACUST UNITED AC 2017. [DOI: 10.1088/1742-6596/847/1/012010] [Citation(s) in RCA: 2] [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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4
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Penev KI, Mequanint K. Multifactorial study and kinetics of signal development in ferrous-methylthymol blue-gelatin gel dosimeters. Med Phys 2017; 44:1948-1957. [DOI: 10.1002/mp.12201] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 02/06/2017] [Accepted: 02/27/2017] [Indexed: 11/06/2022] Open
Affiliation(s)
- Kalin I. Penev
- Department of Chemical and Biochemical Engineering; The University of Western Ontario; London ON Canada N6A5B9
| | - Kibret Mequanint
- Department of Chemical and Biochemical Engineering; The University of Western Ontario; London ON Canada N6A5B9
- Biomedical Engineering Graduate Program; The University of Western Ontario; London ON Canada N6A5B9
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Valente M, Molina W, Silva LC, Figueroa R, Malano F, Pérez P, Santibañez M, Vedelago J. Fricke gel dosimeter with improved sensitivity for low-dose-level measurements. J Appl Clin Med Phys 2016; 17:402-417. [PMID: 27455471 PMCID: PMC5690050 DOI: 10.1120/jacmp.v17i4.5626] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 01/15/2016] [Accepted: 02/10/2016] [Indexed: 11/25/2022] Open
Abstract
Fricke solution has a wide range of applications as radiation detector and dosimetry. It is particularly appreciated in terms of relevant comparative advantages, like tissue‐equivalence when prepared in aqueous media like gel matrix, continuous mapping capability, independence of dose rate and incident direction, as well as linear dose response. This work presents the development and characterization of an improved Fricke gel system, based on modified chemical compositions, making possible its application in clinical radiology due to its improved sensitivity. Properties of standard Fricke gel dosimeter for high‐dose levels are used as a starting point, and suitable chemical modifications are introduced and carefully investigated in order to attain high resolution for low‐dose ranges, like those corresponding to radiology interventions. The developed Fricke gel radiation dosimeter system achieves the expected typical dose‐dependency, showing linear response in the dose range from 20 up to 4000 mGy. Systematic investigations including several chemical compositions are carried out in order to obtain an adequate dosimeter response for low‐dose levels. A suitable composition from among those studied is selected as a good candidate for low‐dose‐level radiation dosimetry consisting of a modified Fricke solution fixed to a gel matrix containing benzoic acid along with sulfuric acid, ferrous sulfate, Xylenol orange, and tridistilled water. Dosimeter samples are prepared in standard vials for in‐phantom irradiation and further characterization by spectrophotometry measuring visible light transmission and absorbance before and after irradiation. Samples are irradiated using typical X‐ray tubes for radiology and calibrated Farmer‐type ionization chamber is used as reference to measure dose rates inside phantoms at vial locations. Once sensitive material composition is optimized, dose‐response curves show significant improvement regarding overall sensitivity for low dose levels. The aim of this work consists of implementing the optimized gel dosimeter to perform direct measurements of absorbed dose in samples irradiated during microcomputed tomography scanning in order to preliminary assess dose levels for further scanning of small animals for further applications in veterinary and paleontology. As a first attempt, dose distributions were measured in water‐equivalent phantoms having dimensions comparable to small animals, 100 to 1000 cm3, approximately. According to the obtained results, it is found that the proposed method shows satisfactory reliability and adequate performance for a promising gel dosimetry system. PACS number(s): 87.53.Bn, 87.57.uq, 87.59.‐e
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Affiliation(s)
- Mauro Valente
- Institute of Physics E. Gaviola - CONICET, Argentina Departamento de Ciencias Físicas, Universidad de La Frontera, Temuco, Chile. University of Cordoba, Argentina.
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6
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Current scenario of biomedical aspect of metal-based nanoparticles on gel dosimetry. Appl Microbiol Biotechnol 2016; 100:4803-16. [DOI: 10.1007/s00253-016-7489-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 03/17/2016] [Accepted: 03/18/2016] [Indexed: 12/12/2022]
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7
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Mann P, Witte M, Armbruster S, Runz A, Lang C, Breithaupt M, Berger M, Biederer J, Karger CP, Moser T. Feasibility of polymer gel dosimetry measurements in a dynamic porcine lung phantom. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/573/1/012079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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8
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Pavoni JF, Neves-Junior WFP, Silveira MA, Ramos PAMM, Haddad CMK, Baffa O. Feasibility on using composite gel-alanine dosimetry on the validation of a multiple brain metastasis radiosurgery VMAT technique. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/573/1/012050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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9
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Senkesen O, Tezcanli E, Buyuksarac B, Ozbay I. Comparison of 3D dose distributions for HDR 192Ir brachytherapy sources with normoxic polymer gel dosimetry and treatment planning system. Med Dosim 2014; 39:266-71. [PMID: 24933316 DOI: 10.1016/j.meddos.2014.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Revised: 02/26/2014] [Accepted: 04/07/2014] [Indexed: 01/27/2023]
Abstract
Radiation fluence changes caused by the dosimeter itself and poor spatial resolution may lead to lack of 3-dimensional (3D) information depending on the features of the dosimeter and quality assurance of dose distributions for high-dose rate (HDR) iridium-192 ((192)Ir) brachytherapy sources is challenging and experimental dosimetry methods used for brachytherapy sources are limited. In this study, we investigated 3D dose distributions of (192)Ir brachytherapy sources for irradiation with single and multiple dwell positions using a normoxic gel dosimeter and compared them with treatment planning system (TPS) calculations. For dose calibration purposes, 100-mL gel-containing vials were irradiated at predefined doses and then scanned in an magnetic resonance (MR) imaging unit. Gel phantoms prepared in 2 spherical glasses were irradiated with (192)Ir for the calculated dwell positions, and MR scans of the phantoms were obtained. The images were analyzed with MATLAB software. Dose distributions and profiles derived with 1-mm resolution were compared with TPS calculations. Linearity was observed between the delivered dose and the reciprocal of the T2 relaxation time constant of the gel. The x-, y-, and z-axes were defined as the sagittal, coronal, and axial planes, respectively, the sagittal and axial planes were defined parallel to the long axis of the source while the coronal plane was defined horizontally to the long axis of the source. The differences between measured and calculated profile widths of 3-cm source length and point source for 70%, 50%, and 30% isodose lines were evaluated at 3 dose levels using 18 profiles of comparison. The calculations for 3-cm source length revealed a difference of > 3mm in 1 coordinate at 50% profile width on the sagittal plane and 3 coordinates at 70% profile width and 2 coordinates at 50% and 30% profile widths on the axial plane. Calculations on the coronal plane for 3-cm source length showed > 3-mm difference in 1 coordinate at 50% and 70% and 2 coordinates at 30% profile widths. The point source measurements and calculations for 50% profile widths revealed a difference > 3mm in 1 coordinate on the sagittal plane and 2 coordinates on the axial plane. The doses of 3 coordinates on the sagittal plane and 4 coordinates on the axial plane could not be evaluated in 30% profile width because of low doses. There was good agreement between the gel dosimetry and TPS results. Gel dosimetry provides dose distributions in all 3 planes at the same time, which enables us to define the dose distributions in any plane with high resolution. It can be used to obtain 3D dose distributions for HDR (192)Ir brachytherapy sources and 3D dose verification of TPS.
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Affiliation(s)
- Oznur Senkesen
- Department of Radiation Oncology, Acibadem Kozyatagi Hospital, Istanbul, Turkey
| | - Evrim Tezcanli
- Department of Radiation Oncology, Acibadem University, Istanbul, Turkey.
| | - Bora Buyuksarac
- Institute of Biomedical Engineering, Bogazici University Istanbul, Turkey
| | - Ismail Ozbay
- Istanbul University, Institute of Oncology, Istanbul, Turkey
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10
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Penev K, Mequanint K. The effect of mixed dopants on the stability of Fricke gel dosimeters. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/444/1/012105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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11
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Penev KI, Mequanint K. Controlling sensitivity and stability of ferrous–xylenol orange–gelatin 3D gel dosimeters by doping with phenanthroline-type ligands and glyoxal. Phys Med Biol 2013; 58:1823-38. [DOI: 10.1088/0031-9155/58/6/1823] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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13
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Doran SJ, Brochard T, Adamovics J, Krstajic N, Bräuer-Krisch E. An investigation of the potential of optical computed tomography for imaging of synchrotron-generated x-rays at high spatial resolution. Phys Med Biol 2010; 55:1531-47. [PMID: 20157228 DOI: 10.1088/0031-9155/55/5/018] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
X-ray microbeam radiation therapy (MRT) is a novel form of treatment, currently in its preclinical stage, which uses microplanar x-ray beams from a synchrotron radiation source. It is important to perform accurate dosimetry on these microbeams, but, to date, there has been no accurate enough method available for making 3D dose measurements with isotropic, high spatial resolution to verify the results of Monte Carlo dose simulations. Here, we investigate the potential of optical computed tomography for satisfying these requirements. The construction of a simple optical CT microscopy (optical projection tomography) system from standard commercially available hardware is described. The measurement of optical densities in projection data is shown to be highly linear (r2=0.999). The depth-of-field (DOF) of the imaging system is calculated based on the previous literature and measured experimentally using a commercial DOF target. It is shown that high quality images can be acquired despite the evident lack of telecentricity and despite DOF of the system being much lower than the sample diameter. Possible reasons for this are discussed. Results are presented for a complex irradiation of a 22 mm diameter cylinder of the radiochromic polymer PRESAGE, demonstrating the exquisite 'dose-painting' abilities available in the MRT hutch of beamline ID-17 at the European Synchrotron Radiation Facility. Dose distributions in this initial experiment are equally well resolved on both an optical CT scan and a corresponding transmission image of radiochromic film, down to a line width of 83 microm (6 lp mm(-1)) with an MTF value of 0.40. A group of 33 microm wide lines was poorly resolved on both the optical CT and film images, and this is attributed to an incorrect exposure time calculation, leading to under-delivery of dose. Image artefacts in the optical CT scan are discussed. PRESAGE irradiated using the microbeam facility is proposed as a suitable material for producing phantom samples for quantitative characterization of optical CT microscopy systems.
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Affiliation(s)
- Simon J Doran
- Department of Physics, University of Surrey, Guildford, UK.
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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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Baldock C. Historical overview of the development of gel dosimetry: Another personal perspective. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1742-6596/164/1/012002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Bosi SG, Naseri P, Baldock C. Light-scattering-induced artifacts in a complex polymer gel dosimetry phantom. APPLIED OPTICS 2009; 48:2427-2434. [PMID: 19412199 DOI: 10.1364/ao.48.002427] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Certain polymer gels become turbid on exposure to ionizing radiation, a property exploited in medical dosimetry to produce three-dimensional dose maps for radiotherapy. These maps can be read using optical computed tomography (CT). A test phantom of complex shape ("layered tube") was developed to investigate the optical properties of polymer gel dosimeters when read using optical CT. Extinction coefficient profiles from tomographically reconstructed slices of the phantom exhibited several artifacts. A simple model invoking scattered light in the gel was able to account for all artifacts, which in a real dosimeter may have been mistaken for other phenomena, resulting in incorrect readings of dose.
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Affiliation(s)
- Stephen G Bosi
- Department of Radiation Oncology, Prince of Wales Hospital, Randwick NSW 2031, Australia.
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Fernandes JP, Pastorello BF, de Araujo DB, Baffa O. Formaldehyde increases MAGIC gel dosimeter melting point and sensitivity. Phys Med Biol 2008; 53:N53-8. [PMID: 18263941 DOI: 10.1088/0031-9155/53/4/n04] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Polymeric gel dosimeters are being used to verify three-dimensional (3D) dose distributions of different types of radiotherapy treatments, especially the most complexes ones. An important factor that can limit the wider use of this kind of dosimeter is temperature, as gel melting can destroy 3D information. This work shows that adding formaldehyde to the gel preparation increases the melting point, allowing its use in warmer environments, including up to body temperature. An addition of 3% in mass of the formaldehyde solution to a MAGIC type gel dosimeter increased its melting point from 25 to 69 degrees C. Also important were a 12.5% increase in gel sensitivity and an expressive decrease in relaxation rate R2 uncertainty.
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Affiliation(s)
- Juliana Polezze Fernandes
- Departamento de Fisica e Matematica, FFCLRP, Universidade de São Paulo, Av Bandeirantes, Ribeirao Preto, SP, Brazil
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