Journal articles: 'Dosimetry applications'

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Bhatt, B. C., and M. S. Kulkarni. "Thermoluminescent Phosphors for Radiation Dosimetry." Defect and Diffusion Forum 347 (December 2013): 179–227. http://dx.doi.org/10.4028/www.scientific.net/ddf.347.179.

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The use of thermoluminescence (TL) as a method for radiation dosimetry of ionizing radiation has been established for many decades and has found many useful applications in various fields, such as personnel and environmental monitoring, retrospective dosimetry, medical dosimetry, space dosimetry, high-dose dosimetry. Method of preparation, studies and applications of thermoluminescence (TL) dosimetric materials are reviewed. Several high sensitivity thermoluminescent dosimeters (TLDs) are now commercially available in different physical forms. These commercial TL dosimeters comply with a set of stringent requirements stipulated by the International Electrotechnical Commission (IEC). Specific features of TL phosphors for thermal neutron, fast neutron and high-energy charged particle (HCP) dosimetry are also considered. Some of the recent developments in the field of optically stimulated luminescence (OSL) and radiophotoluminescence (RPL) are also summarized. Comparative advantages of TL, OSL and RPL dosimeters are given. Results of recent studies of TL in nanosized materials are briefly presented. Future challenges in this field will also be discussed. Contents of Paper

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Gafar, Sameh Mohamed, and Nehad Magdy Abdel-Kader. "Radiation induced degradation of murexide dye in two media for possible use in dosimetric applications." Pigment & Resin Technology 48, no. 6 (November 4, 2019): 540–46. http://dx.doi.org/10.1108/prt-02-2019-0014.

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Purpose The purpose of this paper is to study the effect of gamma-rays on murexide (Mx) dye and its possible use as radiation dosimeters in two different dosimetry systems. The first system depends on the Mx dye as a liquid dosimeter. The second dosimetry system depends also on the same dye but as in a gel form, which is more sensitive to gamma-rays. Design/methodology/approach The prepared Mx (solutions/gels) have a considerable two peaks at 324 and 521 nm that upon irradiation, the intensity of these peaks decreases with the increasing radiation dose. Findings The gamma-ray absorbed dose for these dosimeters was found to be up to 2 kGy for the solution samples and 40 Gy for the gels. Radiation chemical yield, dose response function, radiation sensitivity and before and after-irradiation stability under various conditions were discussed and studied. Practical implications It is expected that the radiolysis of the Mx dye can be used as radiation dosimeters in two different dosimetry systems; liquid and gel dosimeters. This can be applied in a wide range of gamma radiation practical industrial applications in water treatment, food irradiation dosimeters, radiotherapy and fresh food irradiation and seed production. Originality/value Both of the prepared Mx dyes, either as solutions or gel samples, can be facilely prepared from commercially, cheap, safe, available chemicals and suitable for useful applied Mx solutions and gels radiation dosimeters.

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Prestopino, Giuseppe, Enrico Santoni, Claudio Verona, and Gianluca Verona Rinati. "Diamond Based Schottky Photodiode for Radiation Therapy In Vivo Dosimetry." Materials Science Forum 879 (November 2016): 95–100. http://dx.doi.org/10.4028/www.scientific.net/msf.879.95.

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Diamond has long been considered as a suitable material for the fabrication of radiation detectors due to its outstanding physical properties. Even more so in the specific case of radiation therapy dosimetry applications, where the near-tissue equivalence radiation absorption, good spatial resolution and radiation hardness are required. Recently, a synthetic single crystal diamond dosimeter was developed at “Tor Vergata” University in cooperation with PTW-Freiburg, showing excellent dosimetric properties. Such a device was thus commercialized (microDiamondTM, PTW-type 60019) and widely accepted by the medical physics community, due to its reproducibility, reliability, accuracy and versatility. In this work, a novel diamond based dosimeter for in vivo application developed in our laboratories is presented. A basic dosimetric characterization of detector performances was performed under irradiation with 60Co and 6 MV photon beams. Response stability, short and long term reproducibility, fading effect, linearity with dose, dose rate dependence, and temperature dependence were investigated. The detector response was found to be reproducible and dose rate independent in the range between 0.5 and 5 Gy/min. Its temperature dependence was within 0.5% between 25 and 38 ◦C, and negligible fading effect was observed. The obtained results indicate the proposed novel diamond device as a promising candidate for in vivo dosimetry in radiation therapy application.

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Murthy, K. V. R. "Applications of TLDs in Radiation Dosimetry." Defect and Diffusion Forum 341 (July 2013): 211–30. http://dx.doi.org/10.4028/www.scientific.net/ddf.341.211.

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An increasing amount of public interest in environmental monitoring programmes is being focused on the environmental impact of radiation arising from nuclear power operations and the corresponding detection of slight variations in the natural radiation background. The primary objective of individual monitoring for external radiation is to assess, and thus limit, radiation doses to individual workers. Supplementary objectives are to provide information about the trends of these doses and about the conditions in places of work and to give information in the event of accidental exposure. Depending on the kind of radiation hazard, the ICRP recommended maximum permissible dose (MPD) values. These are the maximum dose equivalent values, which are not expected to cause appreciable body injury to a person during his lifetime. Thermoluminescent Dosimetry (TLD) has been developed during 1960-70 for various applications in medicine and industry. TLD, the most advanced and most intensively studied integrating dosimeter system, has now reached the stage at which it may replace or supplement film dosimetry. TLD systems are widely applied to environmental monitoring programmes near nuclear installations. TLD systems with high reproducibility in the milli roentgen dose range are required in order to measure exposures equal to that resulting from an exposure rate of 10μR h-1 during field periods of from several days up to a year. A brief list of applications specific to radiation oncology is given here. In radiation oncology dosimetric accuracy demanded is of the order of 2-5%. TLDs offer a clear solution since their precision meets this criteria. Contents

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Murthy, K. V. R. "Thermoluminescence and its Applications: A Review." Defect and Diffusion Forum 347 (December 2013): 35–73. http://dx.doi.org/10.4028/www.scientific.net/ddf.347.35.

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The present review article contains various applications of Thermoluminescence. The phenomena of thermoluminescence (TL) or thermally stimulated luminescence (TSL) and optically stimulated luminescence (OSL) are widely used for measurement of radiation doses from ionizing radiations, viz. x-rays, γ rays and β particles. The applications of TL are initiated in the field of Geology followed by Archaeology, personal dosimetry, material characterization and many more to name. The TL technique has been found to be useful in dating specimens of geologically recent origin where all other conventional methods fail. It has been found to be highly successful in dating ancient pottery samples. The TL/OSL dating is done from a quartz grain, which is collected from pottery or brick, by reading the TL-output. The main basis in the Thermoluminescence Dosimetry (TLD) is that TL output is directly proportional to the radiation dose received by the phosphor and hence provides the means of estimating the dose from unknown irradiations. The TL dosimeters are being used in personnel, environmental and medical dosimetry. During the last two decades, OSL based dosimeters have also been used for various applications. Natural and induced TL signals can be used to explore mineral, oil and natural gas. The present review presents TL theory, TL of minerals, salt, cement, salt crystals from pickles, and low temperature thermoluminescence (LLTL) of few agricultural products. Contents of Paper

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Dhakal, Rabin, Mohammad Yosofvand, and Hanna Moussa. "Development and Application of MAGIC-f Gel in Cancer Research and Medical Imaging." Applied Sciences 11, no. 17 (August 24, 2021): 7783. http://dx.doi.org/10.3390/app11177783.

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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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Mohyedin, Muhammad Zamir, Hafiz Mohd Zin, Mohd Zulfadli Adenan, and Ahmad Taufek Abdul Rahman. "A Review of PRESAGE Radiochromic Polymer and the Compositions for Application in Radiotherapy Dosimetry." Polymers 14, no. 14 (July 16, 2022): 2887. http://dx.doi.org/10.3390/polym14142887.

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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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Algain, Ibrahim, Mehenna Arib, Said A. Farha Al-Said, and Hossam Donya. "Dosimetric Study of Heat-Treated Calcium–Aluminum–Silicon Borate Dosimeter for Diagnostic Radiology Applications." Sensors 23, no. 2 (January 16, 2023): 1011. http://dx.doi.org/10.3390/s23021011.

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The production of thermoluminescence (TL) dosimeters fabricated from B2O3-CaF2-Al2O3-SiO2 doped with Cu and Pr for use in diagnostic radiology is the main goal of this research. The TL samples were synthesized via the melt-quench technique processed by melting the mixture at 1200 °C for 1 h, and, after cooling, the sample thus created was divided into two samples and retreated by heating for 2 h (referred to as TLV30) and for 15 h (referred to as TLV17). SEM and EDS analyses were performed on the TL samples to confirm the preparation process and to investigate the effects of irradiation dosimetry on the TL samples. Furthermore, the TL samples were irradiated with γ-rays using a 450 Ci 137Cs irradiator and variable X-ray beams (5–70 mGy). Two important diagnostic radiology applications were considered: CT (6–24 mGy) and mammography (2.72–10.8 mGy). Important dosimetric properties, such as the glow curves, reproducibility, dose–response linearity, energy dependence, minimum dose detectability and fading, were investigated for the synthetized samples (TLV17 and TLV30), the results of which were compared with the Harshaw TLD-100. The TLV17 dosimeter showed higher sensitivity than TLV30 in all applied irradiation procedures. The dose–response linearity coefficients of determination R2 for TLV17 were higher than TLD-100 and TLV30 in some applications and were almost equal in others. The reproducibility results of TLV17, TLV30 and TLD-100 were less than 5%, which is acceptable. On the other hand, the results of the fading investigations showed that, in general, TLV17 showed less fading than TLV30. Both samples showed a significant decrease in this regard after the first day, and then the signal variation became essentially stable though with a slight decrease until the eighth day. Therefore, it is recommended to read the TL dosimeters after 24 h, as with TLD-100. The SEM images confirmed the existence of crystallization, whilst the EDS spectra confirmed the presence of the elements used for preparation. Furthermore, we noticed that TLV17 had grown dense crystals that were larger in size compared to those of TLV30, which explains the higher sensitivity in TLV17. Overall, despite the fading, TLV17 showed greater radiation sensitivity and dose–response linearity compared with TLD-100. The synthetized TL samples showed their suitability for use as dosimeters in diagnostic radiology radiation dosimetry.

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Gasiorowski, Andrzej, Piotr Szajerski, and Jose Francisco Benavente Cuevas. "Use of Terbium Doped Phosphate Glasses for High Dose Radiation Dosimetry—Thermoluminescence Characteristics, Dose Response and Optimization of Readout Method." Applied Sciences 11, no. 16 (August 5, 2021): 7221. http://dx.doi.org/10.3390/app11167221.

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The phosphate glass samples doped with Tb2O3 oxide (general formula: P2O5-Al2O3-Na2O-Tb2O3) were synthesized and studied for usage in high-dose radiation dosimetry (for example, in high-activity nuclear waste disposals). The influence of terbium concentration on thermoluminescent (TL) signals was analyzed. TL properties of glasses were investigated using various experimental techniques such as direct measurements of TL response vs. radiation dose, Tmax–Tstop and VHR (various heating rate) methods, and glow curve deconvolution analysis. The thermoluminescence dosimetry (TLD) technique was used as the main investigation tool to study detectors’ dose responses. It has been proved that increasing the concentration of terbium oxide in glass matrices significantly increases the thermoluminescence yield of examined material. For the highest dose range (up to 35 kGy), the dependence of the integrated thermoluminescent signals vs. dose can be considered as a saturation-type curve. Additional preheating of samples improves linearity of signal vs. dose dependencies and leads to a decrease of the signal loss over time. All obtained data suggest that investigated material can be used in high-dose radiation dosimetry. Additional advantages of the investigated dosimetric system are its potential ability to re-use the same dosimeters multiple times and the fact that reading dosimeters only requires usage of a basic TL reader without any modifications.

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Sholom, Sergey, Stephen W. S. McKeever, Maria B. Escalona, Terri L. Ryan, and Adayabalam S. Balajee. "A comparative validation of biodosimetry and physical dosimetry techniques for possible triage applications in emergency dosimetry." Journal of Radiological Protection 42, no. 2 (March 22, 2022): 021515. http://dx.doi.org/10.1088/1361-6498/ac5815.

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Abstract Large-scale radiological accidents or nuclear terrorist incidents involving radiological or nuclear materials can potentially expose thousands, or hundreds of thousands, of people to unknown radiation doses, requiring prompt dose reconstruction for appropriate triage. Two types of dosimetry methods namely, biodosimetry and physical dosimetry are currently utilized for estimating absorbed radiation dose in humans. Both methods have been tested separately in several inter-laboratory comparison exercises, but a direct comparison of physical dosimetry with biological dosimetry has not been performed to evaluate their dose prediction accuracies. The current work describes the results of the direct comparison of absorbed doses estimated by physical (smartphone components) and biodosimetry (dicentric chromosome assay (DCA) performed in human peripheral blood lymphocytes) methods. For comparison, human peripheral blood samples (biodosimetry) and different components of smartphones, namely surface mount resistors (SMRs), inductors and protective glasses (physical dosimetry) were exposed to different doses of photons (0–4.4 Gy; values refer to dose to blood after correction) and the absorbed radiation doses were reconstructed by biodosimetry (DCA) and physical dosimetry (optically stimulated luminescence (OSL)) methods. Additionally, LiF:Mg,Ti (TLD-100) chips and Al2O3:C (Luxel) films were used as reference TL and OSL dosimeters, respectively. The best coincidence between biodosimetry and physical dosimetry was observed for samples of blood and SMRs exposed to γ-rays. Significant differences were observed in the reconstructed doses by the two dosimetry methods for samples exposed to x-ray photons with energy below 100 keV. The discrepancy is probably due to the energy dependence of mass energy-absorption coefficients of the samples extracted from the phones. Our results of comparative validation of the radiation doses reconstructed by luminescence dosimetry from smartphone components with biodosimetry using DCA from human blood suggest the potential use of smartphone components as an effective emergency triage tool for high photon energies.

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Piotrowski, Igor, Aleksandra Dawid, Katarzyna Kulcenty, and Wiktoria Maria Suchorska. "Use of Biological Dosimetry for Monitoring Medical Workers Occupationally Exposed to Ionizing Radiation." Radiation 1, no. 2 (March 31, 2021): 95–115. http://dx.doi.org/10.3390/radiation1020009.

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Medical workers are the largest group exposed to man-made sources of ionizing radiation. The annual doses received by medical workers have decreased over the last several decades, however for some applications, like fluoroscopically guided procedures, the occupational doses still remain relatively high. Studies show that for some procedures the operator and staff still use insufficient protective and dosimetric equipment, which might cause an underestimation of medical exposures. Physical dosimetry methods are a staple for estimating occupational exposures, although due to the inconsistent use of protection measures, an alternative method such as biological dosimetry might complement the physical methods to achieve a more complete picture. Such methods were used to detect exposures to doses as low as 0.1 mSv/year, and could be useful for a more accurate assessment of genotoxic effects of ionizing radiation in medical workers. Biological dosimetry is usually based on the measurement of the effects present in peripheral blood lymphocytes. Although some methods, such as chromosome aberration scoring or micronucleus assay, show promising results, currently there is no one method recognized as most suitable for dosimetric application in the case of chronic, low-dose exposures. In this review we decided to evaluate different methods used for biological dosimetry in assessment of occupational exposures of medical workers.

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Rabaeh, Khalid, and Ahmed Basfar. "Optical evaluation of dithizone solution as a new radiochromic dosimeter." Pigment & Resin Technology 49, no. 4 (February 28, 2020): 249–53. http://dx.doi.org/10.1108/prt-10-2019-0091.

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Purpose The purpose of this paper is to propose a new dithizone solution dosimeter for high radiation applications such as polymers applications and food irradiation. Design/methodology/approach Gamma-rays cell of Co-60 source with 8.4 kGy/h dose rate was used to irradiate the dithizone solutions at different irradiation temperatures. The optical measurements of unirradiated and irradiated dithizone dye solution dosimeters were performed using a UV/VIS spectrophotometer at absorption peaks of 421 and 515 nm. Findings The new dosimeter improved significantly with the increase of dithizone dye concentrations from 0.025 to 0.1 mM. The dosimeter shows a perfect pre- and post-irradiation stability after irradiation for five days. Because of irradiation temperature dependence, the dithizone solution dosimeter should be corrected under actual processing conditions. Practical implications Dosimetry is a key point in quality control of radiation processing to assure that uniform and correct radiation doses are delivered to a region of interest. Therefore, this study introduces a dithizone solution dosimeter for high-dose radiation applications such as food irradiation, polymers applications and agriculture. Originality/value Ionizing radiation interacted with the ethanol solvent, resulting in the formation of free radicals, then these free radicals interacted with the dithizone molecule and changed the dye color from yellow to orange.

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Omanwar, S. K., K. A. Koparkar, and Hardev Singh Virk. "Recent Advances and Opportunities in TLD Materials: A Review." Defect and Diffusion Forum 347 (December 2013): 75–110. http://dx.doi.org/10.4028/www.scientific.net/ddf.347.75.

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Thermoluminescence (TL) is the thermally stimulated emission of light from an insulator or a semiconductor following the previous absorption of energy from ionizing radiation. TL dosimetry is used in many scientific and applied fields such as radiation protection, radiotherapy, industry, and environmental and space research, using many different materials. The basic demands of a thermoluminescent dosimeter (TLD) are good reproducibility, low hygroscopicity, and high sensitivity for very low dose measurements and good response at high doses in radiotherapy and in mixed radiation fields. In this review, we have discussed the past developments and the future opportunities in TLD materials and our efforts to make better future use of low cost materials in TLD applications. For this we have studied and discussed two efficient TLD phosphors with low cost and simple method of preparation on large scale for TLD materials. One of the phosphors is LiF:Mg,Cu,P (LiF: MCP), and another one is LiCaAlF6:Eu, which has the potential to replace conventionally used CaSO4:Dy TL dosimeter. LiF: MCP and LiCaAlF6: Eu phosphors are potential candidates for TL dosimetry and could be good replacement for commercially available phosphors. Apart from this, we have also studied thermoluminescence in Aluminate and Borate materials. We have discussed in detail all three types of TLD materials. First, our study includes complete detail of material properties, methods and dosimetric characterizations of LiF: MCP Phosphor; second, it includes a new TL Dosimeter, LiCaAlF6: Eu and its dosimetric characterizations; and lastly on some TL properties of Li5AlO4: Mn and MgB4O7: Dy,Na. In this review, we discus some recent developments in radiation dosimetry with regards to the measurement techniques and material preparations. Although many materials have been and are currently being studied for TLD, still there is a scope for the improvement in the material properties useful for the TLD, and the synthesis of new, more suitable materials. Contents of Paper

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Cipa, J., L. Trinkler, and B. Berzina. "Thermoluminescence Response of AlN+Y2O3 Ceramics to Sunlight and X-Ray Irradiation." Latvian Journal of Physics and Technical Sciences 58, no. 1 (January 29, 2021): 3–14. http://dx.doi.org/10.2478/lpts-2021-0001.

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Abstract AlN is a wide band gap material with promising properties for dosimetric applications, especially in UV dosimetry. In the present research, the thermoluminescence method is used in order to better understand sunlight and X-ray irradiation effects on yttria doped AlN ceramics. In general, the TL response is characterised by a broad TL peak with maxima around 400–450 K and a TL emission spectrum with UV (400 nm), Blue (480 nm) and Red (600 nm) bands. Compared to the X-ray irradiation, sunlight irradiation creates a wider TL glow curve peak with a maximum shifted to higher temperatures by 50 K. Furthermore, in the TL emission spectra of AlN irradiated with sunlight the UV band is suppressed. The reasons of the TL peculiarities under two types of irradiation are discussed. Practical application of AlN ceramics as material for UV light TL dosimetry and, in particular, for sunlight dosimetry is estimated.

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Paprocki, K., J. Winiecki, R. Kabacińska, K. Przegietka, M. Szybowicz, and K. Fabisiak. "Thermoluminescence properties of undoped diamond films deposited using HF CVD technique." Materials Science-Poland 35, no. 4 (March 21, 2018): 785–90. http://dx.doi.org/10.1515/msp-2017-0103.

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Abstract Natural diamond has been considered as a perspective material for clinical radiation dosimetry due to its tissuebiocompatibility and chemical inertness. However, the use of natural diamond in radiation dosimetry has been halted by the high market price. The recent progress in the development of CVD techniques for diamond synthesis, offering the capability of growing high quality diamond layers, has renewed the interest in using this material in radiation dosimeters having small geometricalsizes. Polycrystalline CVD diamond films have been proposed as detectors and dosimeters of β and α radiation with prospective applications in high-energy photon dosimetry. In this work, we present a study on the TL properties of undoped diamond film samples grown by the hot filament CVD (HF CVD) method and exposed to β and α radiation. The glow curves for both types of radiation show similar character and can be decomposed into three components. The dominant TL peaks are centered at around 610 K and exhibit activation energy of the order of 0.90 eV.

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Ibbott, Geoffrey S. "Applications of gel dosimetry." Journal of Physics: Conference Series 3 (January 1, 2004): 58–77. http://dx.doi.org/10.1088/1742-6596/3/1/007.

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Merkis, Mantvydas, Judita Puišo, Diana Adliene, and Jurgita Laurikaitiene. "Development and Characterization of Silver Containing Free Standing Polymer FILMS for Dosimetry Applications." Polymers 13, no. 22 (November 13, 2021): 3925. http://dx.doi.org/10.3390/polym13223925.

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Polymer gels and films, due to their near equivalence to biological tissue, are amongst the most promising future dosimetry tools for medical applications. The application of polymer dose gels is limited by the sensitivity of dose readout methods and dose gel properties. It is a challenge to find suitable dosimeters for registration of doses delivered to the target by orthovoltage therapy units. The application of metal-particle-enriched polymer composites for dose registration in X-ray therapy might be an elegant solution, especially if recent dose-reading technologies exploring advantages of different physical phenomena are involved. In this work, X-rays from the orthovoltage therapy range were used for the irradiation of experimental samples. In addition, radiation-induced processes of formation of silver nanoparticles in AgNO3–PVA gels and in free standing AgNO3PVA films, also containing some additional solvents, namely glycerol, ethanol, and isopropanol, have been investigated, with the aim to apply the developed composites for medical dosimetry purposes. A simple and environmentally friendly method for the formation of free-standing AgPVA films at room temperature was proposed and realized for preparing AgPVA films for investigation. Radiation-induced synthesis of silver nanoparticles in AgPVA composites was investigated, analyzing LPSR-based UV-VIS spectral changes to the irradiated films with respect to irradiation doses, and dose-related tendencies were also evaluated. It was shown that AgPVA films were more sensitive for detection of doses from the interval 0–1.0 Gy, thus indicating potential application of AgPVA films for dosimetry purposes.

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Elter, A., S. Dorsch, M. Marot, C. Gillmann, W. Johnen, A. Runz, C. K. Spindeldreier, S. Klüter, C. P. Karger, and P. Mann. "RSC: Gel dosimetry as a tool for clinical implementation of image-guided radiotherapy." Journal of Physics: Conference Series 2167, no. 1 (January 1, 2022): 012020. http://dx.doi.org/10.1088/1742-6596/2167/1/012020.

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Abstract The implementation of new image-guided radiotherapy (IGRT) treatment techniques requires the development of new quality assurance (QA) methods including geometric and dosimetric validation of the applied dose in 3D. Polymer gels (PG) provide a promising tool to perform such tests. However, to be used in a large variety of clinical applications, the PG must be flexibly applicable. In this work, we present a variety of phantoms used in clinical routine to perform both hardware and workflow tests in IGRT. This includes the validation of isocenter accuracy in magnetic resonance (MR)-guided RT (MRgRT) and end-to-end tests of online adaptive treatment techniques for inter- and intra-fraction motion management in IGRT. The phantoms are equipped with one or more PG containers of different materials including 3D printed containers to allow for 3D dosimetry in arbitrarily shaped structures. The proposed measurement techniques and phantoms provide a flexible application and show a clear benefit of PG for 3D dosimetry in combination with end-to-end tests in many clinical QA applications.

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Bolch, Wesley E. "Practical Applications of Internal Dosimetry." Journal of Applied Clinical Medical Physics 3, no. 4 (October 2002): 323. http://dx.doi.org/10.1120/1.1506614.

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Berger, Carol D. "Practical Applications of Internal Dosimetry,." Health Physics 83, no. 6 (December 2002): 920–21. http://dx.doi.org/10.1097/00004032-200212000-00022.

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Akhavanallaf, Azadeh, Hadi Fayad, Yazdan Salimi, Antar Aly, Hassan Kharita, Huda Al Naemi, and Habib Zaidi. "An update on computational anthropomorphic anatomical models." DIGITAL HEALTH 8 (January 2022): 205520762211119. http://dx.doi.org/10.1177/20552076221111941.

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The prevalent availability of high-performance computing coupled with validated computerized simulation platforms as open-source packages have motivated progress in the development of realistic anthropomorphic computational models of the human anatomy. The main application of these advanced tools focused on imaging physics and computational internal/external radiation dosimetry research. This paper provides an updated review of state-of-the-art developments and recent advances in the design of sophisticated computational models of the human anatomy with a particular focus on their use in radiation dosimetry calculations. The consolidation of flexible and realistic computational models with biological data and accurate radiation transport modeling tools enables the capability to produce dosimetric data reflecting actual setup in clinical setting. These simulation methodologies and results are helpful resources for the medical physics and medical imaging communities and are expected to impact the fields of medical imaging and dosimetry calculations profoundly.

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Lebel-Cormier, Marie-Anne, Tommy Boilard, Luc Beaulieu, and Martin Bernier. "Real-Time Temperature Correction of Medical Range Fiber Bragg Gratings Dosimeters." Sensors 23, no. 2 (January 12, 2023): 886. http://dx.doi.org/10.3390/s23020886.

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The interest in fiber Bragg gratings dosimeters for radiotherapy dosimetry lies in their (i) submillimeter size, (ii) multi-points dose measurements, and (iii) customizable spatial resolution. However, since the radiation measurement relies on the thermal expansion of the surrounding polymer coating, such sensors are strongly temperature dependent, which needs to be accounted for; otherwise, the errors on measurements can be higher than the measurements themselves. In this paper, we test and compare four techniques for temperature compensation: two types of dual grating techniques using different coatings, a pre-irradiation and post-irradiation temperature drift technique, which is used for calorimetry, and finally, we developed a real-time interpolated temperature gradient for the multi-points dosimetry technique. We show that, over these four tested techniques, the last one outperforms the others and allows for real-time temperature correction when an array of 13 fiber Bragg gratings spatially extending over the irradiation zone is used. For a 20 Gy irradiation, this technique reduces the measurement errors from 200% to about 10%, making it suitable for a radiotherapy dose range. Temperature correction for medical low-dose range dosimetry is a first in our field and is essential for clinical FBG dosimetry applications.

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Rech, Amanda Burg, Angela Kinoshita, Paulo Marcos Donate, Otaciro Rangel Nascimento, and Oswaldo Baffa. "Electron Spin Resonance Dosimetry Studies of Irradiated Sulfite Salts." Molecules 27, no. 20 (October 19, 2022): 7047. http://dx.doi.org/10.3390/molecules27207047.

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The study of new materials for radiation dosimetry is important to improve the present state of the art and to help in cases of accidents for retrospective dosimetry. Sulfites are compounds that contain a sulfur ion, widely used in the food industry. Due to the significant application of these compounds, sulfites are interesting candidates for accidental dosimetry, as fortuitous radiation detectors. The presence of the SO3− anion enables its detection by electron spin resonance (ESR) spectroscopy. The Dose–Response behavior, signal stability and other spectral features were investigated for sodium sulfite, sodium bisulfite, sodium metabisulfite and potassium metabisulfite, all in crystalline forms. The ESR spectrum of salts presented stability and proportional response with dose, presenting potential for dosimetry applications.

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Ha, Xuan Vinh, Phan Thao Tien Doan, and Chi Thang Nguyen. "Preparation of Tb³⁺-doped K₂GdF₅ Used to Neutron Dosimetry." Nuclear Science and Technology 4, no. 4 (December 30, 2014): 30–37. http://dx.doi.org/10.53747/jnst.v4i4.241.

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The neutron absorption section of gadolinium atom is very high, so that the K2GdF5 crystals doped with Tb3+ ions have been studied for neutron dosimetry by the thermoluminescence (TL) method. The K2GdF5 crystals doped 2%, 3% and 5% concentrations of Tb3+ ions were synthesized by solid state reaction method. The TL properties were studied after the exposure of the samples to neutron source. The experimental results showed that the TL glow-curves of K2GdF5:Tb3+ has the simple, suitable shape for the dosimetry applications. The TL sensitivity of this material is higher than that of commercial TLD-100 and TLD-900 dosimeters. The thermal fading effect of Tb3+-doped K2GdF5 is very low. The glow curve consists of the main peak at temperature of 202oC. The glow curve deconvolution into individual the peaks showed that the curve had a main peak at 202oC, and kinetic order b = 2. The study results indicated that the K2GdF5 doped with Tb3+ is very remarkable material can be applied in neutron dosimetry field.

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Olusoji, Olugbenga J., Crystal Penner, Camille Bélanger-Champagne, Wern Kam, Michael Martyn, Peter Woulfe, Cornelia Hoehr, and Sinead O’Keeffe. "Dosimetric Application of Phosphorus Doped Fibre for X-ray and Proton Therapy." Sensors 21, no. 15 (July 30, 2021): 5157. http://dx.doi.org/10.3390/s21155157.

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Phosphorous-doped silica optical fibres with a core diameter of 4 µm were tested in X-ray and proton fields for application in cancer therapy dosimetry. Specifically, the radiation-induced attenuation was investigated in terms of linearity in deposited dose in 15 MV and 6 MV photons and 74 MeV protons, as well as Bragg-peak detection along the proton track. Fibres were found to demonstrate linear relative dose response in both radiation modalities, but possible saturation did occur at the high linear energy transfer of the Bragg peak. This demonstrates the possibility to use these fibres as a relative dosimeter for radiation therapy applications.

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Bekhit, Mohamad, Asmaa Sobhy, Zakaria I. Ali, and Sameh M. Gafar. "Efficient monitoring of dosimetric behaviour for copper nanoparticles through studying its optical properties." Radiochimica Acta 107, no. 6 (June 26, 2019): 523–29. http://dx.doi.org/10.1515/ract-2018-3010.

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Abstract A novel high-dose dosimeter based on γ radiation reduction of copper ions and formation of copper metal inside polymer matrix were investigated. γ radiation induced synthesis of copper nanoparticles (CuNPs) in poly vinyl alcohol films were studied by UV-Visible Spectrophotometer, X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The optical absorption spectra showed that the Cu/PVA nanocomposite films have surface plasmon resonance (SPR) of copper nanoparticles which depending on irradiation doses. Upon γ irradiation these films turns its color from faint blue to deep reddish brown depending on metal ion concentration. The XRD pattern and FTIR spectrum confirm the formation of the CuNPs. The response of Cu/PVA nanocomposite dosimeters depends on both the irradiation doses and concentration of copper precursor. The dose range for these films was from 50 to 650 kGy, revealing its important applications for high dose dosimetry. Cu/PVA nanocomposites films exhibit good post-irradiation stability in dark and light.

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Lassmann, Michael, Christoph Reiners, and Markus Luster. "Dosimetry and thyroid cancer: the individual dosage of radioiodine." Endocrine-Related Cancer 17, no. 3 (September 2010): R161—R172. http://dx.doi.org/10.1677/erc-10-0071.

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Adjuvant therapy of differentiated thyroid cancer with radioactive iodine (131I) is a standard procedure for the ablation of remnant thyroid tissue following surgery and for the treatment of iodine-avid metastases. Presently, there are two dosimetric concepts for the treatment of thyroid cancer using radioiodine: a) the bone marrow dose limited approach and b) lesion-based dosimetry. Both concepts and their clinical applications are described. In addition, the use of 124I as a diagnostic and dosimetric agent is discussed. Treatment of children and adolescents with radioiodine requires special precautions; individualized approaches in this setting are reviewed. The limitations of treatments aiming at high absorbed doses are addressed as well as the doses to normal organs. Finally, new concepts for further elaborating the potential of thyroid cancer treatment using 131I are introduced.

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Burruel-Ibarra, S. E., C. Cruz-Vázquez, R. Bernal, J. R. Martínez-Castelo, A. R. García Haro, and V. R. Orante-Barrón. "Synthesis and Thermoluminescent Properties of New ZnO Phosphors." Materials Science Forum 755 (April 2013): 139–44. http://dx.doi.org/10.4028/www.scientific.net/msf.755.139.

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In this work, results on the thermoluminescence dosimetry properties of beta particle irradiated ZnO obtained by thermal annealing of chemically synthesized ZnS are reported. ZnS powder was sintered at 950 °C during 24 h in air, in order to obtain pellet-shaped ZnO samples. The thermoluminiescence (TL) intensity of ZnO previously exposed to beta radiation increased as the dose increased in the 0.025-6.4 kGy interval studied. Characteristic glow curves exhibited two emission maxima at ~ 94 and ~ 341 °C. The dosimetric peak located at ~ 341 °C shifted towards lower temperatures as the dose increased, which indicates that second-order kinetic processes are involved in the thermoluminiescence emission. The dose response of ZnO showed a linear behaviour in the 0.025 Gy-0.8 kGy dose interval, which makes this material suitable and promising for medical, industrial and also space dosimetry applications. The thermoluminescence total signal faded down 48 % 6 h after irradiation and showed an asymptotic behaviour for longer times, due mainly to the ~ 341 °C stable and dosimetric glow peak.

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Kegel, G. H. R. "Fast Neutrons: Generation, Dosimetry, and Applications." IEEE Transactions on Electrical Insulation EI-21, no. 3 (June 1986): 271–74. http://dx.doi.org/10.1109/tei.1986.349060.

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Vatnitsky, S. M., V. S. Khrunov, V. I. Fominych, and E. Schuele. "Diamond Detector Dosimetry for Medical Applications." Radiation Protection Dosimetry 47, no. 1-4 (May 1, 1993): 515–18. http://dx.doi.org/10.1093/oxfordjournals.rpd.a081798.

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Kron, T. "Applications of Thermoluminescence Dosimetry in Medicine." Radiation Protection Dosimetry 85, no. 1 (September 1, 1999): 333–40. http://dx.doi.org/10.1093/oxfordjournals.rpd.a032865.

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Vatnitsky, S. M., V. S. Khrunov, V. I. Fominych, and E. Schuele. "Diamond Detector Dosimetry for Medical Applications." Radiation Protection Dosimetry 47, no. 1-4 (May 1, 1993): 515–18. http://dx.doi.org/10.1093/rpd/47.1-4.515.

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Whitehead, A. J., R. Airey, C. M. Buttar, J. Conway, G. Hill, S. Ramkumar, G. A. Scarsbrook, R. S. Sussmann, and S. Walker. "CVD diamond for medical dosimetry applications." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 460, no. 1 (March 2001): 20–26. http://dx.doi.org/10.1016/s0168-9002(00)01090-1.

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Bruzzi, M., M. Bucciolini, M. Casati, D. Menichelli, C. Talamonti, C. Piemonte, and B. G. Svensson. "Epitaxial silicon devices for dosimetry applications." Applied Physics Letters 90, no. 17 (April 23, 2007): 172109. http://dx.doi.org/10.1063/1.2723075.

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Chiodini, N., A. Vedda, and I. Veronese. "Rare Earth Doped Silica Optical Fibre Sensors for Dosimetry in Medical and Technical Applications." Advances in Optics 2014 (October 14, 2014): 1–9. http://dx.doi.org/10.1155/2014/974584.

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Radioluminescence optical fibre sensors are gaining importance since these devices are promising in several applications like high energy physics, particle tracking, real-time monitoring of radiation beams, and radioactive waste. Silica optical fibres play an important role thanks to their high radiation hardness. Moreover, rare earths may be incorporated to optimise the scintillation properties (emission spectrum, decay time) according to the particular application. This makes doped silica optical fibres a very versatile tool for the detection of ionizing radiation in many contexts. Among the fields of application of optical fibre sensors, radiation therapy represents a driving force for the research and development of new devices. In this review the recent progresses in the development of rare earth doped silica fibres for dosimetry in the medical field are described. After a general description of advantages and challenges for the use of optical fibre based dosimeter during radiation therapy treatment and diagnostic irradiations, the features of the incorporation of rare earths in the silica matrix in order to prepare radioluminescent optical fibre sensors are presented and discussed. In the last part of this paper, recent results obtained by using cerium, europium, and ytterbium doped silica optical fibres in radiation therapy applications are reviewed.

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Zwierzchowski, Grzegorz, Grzegorz Bieleda, and Janusz Skowronek. "Quality assurance procedures based on dosimetric, gamma analysis as a fast reliable tool for commissioning brachytherapy treatment planning systems." Radiology and Oncology 51, no. 4 (November 29, 2017): 469–74. http://dx.doi.org/10.1515/raon-2017-0050.

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Abstract Background Fast and easily repeatable methods for commissioning procedures for brachytherapy (BT) treatment planning systems (TPS) are needed. Radiochromic film dosimetry with gamma analysis is widely used in external beam quality assurance (QA) procedures and planar film dosimetry is also increasingly used for verification of the dose distribution in BT applications. Using the gamma analysis method for comparing calculated and measured dose data could be used for commissioning procedures of the newly developed TG-186 and MBDCA calculation algorithms. The aim of this study was dosimetric verification of the calculation algorithm used in TPS when the CT/MRI ring applicator is used. Materials and methods Ring applicators with 26 and 30 mm diameters and a 60 mm intra-uterine tube with 60° angle were used for verification. Gafchromic® EBT films were used as dosimetric media. Dose grids, corresponding to each plane (dosimetric film location), were exported from the TPS as a raw data. Gafchromic® films were digitized after irradiation. gamma analysis of the data were performed using the OMNI Pro I’mRT® system, as recommended by the AAPM TG-119 rapport criterion for gamma analysis of 3%, 3 mm and a level of 95%. Results For the 26 mm and 30 mm rings, the average gamma ranged, respectively, from 0.1 to 0.44 and from 0.1 to 0.27. In both cases, 99% of the measured points corresponded with the calculated data. Conclusions This analysis showed excellent agreement between the dose distribution calculated with the TPS and the doses measured by Gafchromic films. This finding confirms the viability of using film dosimetry in BT.

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Tino, Rance, Adam Yeo, Martin Leary, Milan Brandt, and Tomas Kron. "A Systematic Review on 3D-Printed Imaging and Dosimetry Phantoms in Radiation Therapy." Technology in Cancer Research & Treatment 18 (January 1, 2019): 153303381987020. http://dx.doi.org/10.1177/1533033819870208.

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Introduction: Additive manufacturing or 3-dimensional printing has become a widespread technology with many applications in medicine. We have conducted a systematic review of its application in radiation oncology with a particular emphasis on the creation of phantoms for image quality assessment and radiation dosimetry. Traditionally used phantoms for quality assurance in radiotherapy are often constraint by simplified geometry and homogenous nature to perform imaging analysis or pretreatment dosimetric verification. Such phantoms are limited due to their ability in only representing the average human body, not only in proportion and radiation properties but also do not accommodate pathological features. These limiting factors restrict the patient-specific quality assurance process to verify image-guided positioning accuracy and/or dose accuracy in “water-like” condition. Methods and Results: English speaking manuscripts published since 2008 were searched in 5 databases (Google Scholar, Scopus, PubMed, IEEE Xplore, and Web of Science). A significant increase in publications over the 10 years was observed with imaging and dosimetry phantoms about the same total number (52 vs 50). Key features of additive manufacturing are the customization with creation of realistic pathology as well as the ability to vary density and as such contrast. Commonly used printing materials, such as polylactic acid, acrylonitrile butadiene styrene, high-impact polystyrene and many more, are utilized to achieve a wide range of achievable X-ray attenuation values from −1000 HU to 500 HU and higher. Not surprisingly, multimaterial printing using the polymer jetting technology is emerging as an important printing process with its ability to create heterogeneous phantoms for dosimetry in radiotherapy. Conclusion: Given the flexibility and increasing availability and low cost of additive manufacturing, it can be expected that its applications for radiation medicine will continue to increase.

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Komeijani, A., H. Bagheri, and B. Shekarchi. "Surface potential uniformity and sensitivity of large-area PTFE electret discs of different thicknesses produced by a modified corona poling rotating system for dosimetry applications." Journal of Advanced Dielectrics 09, no. 06 (December 2019): 1950050. http://dx.doi.org/10.1142/s2010135x19500504.

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In this study, large-area (6-cm diameter) Teflon polytetrafluoroethylene (PTFE) discs of different thicknesses (0.2-, 0.5- and 1 -mm) were negatively and positively charged by using the “modified single point-to-plane corona poling rotating system”. The effects of some crucial parameters of the PTFE disc as well as the modified corona poling rotating system on the PTFE surface potential uniformity such as: (a) PTFE disc thickness, (b) PTFE disc polarity and (c) needle-to-PTFE disc distance were successfully reported. Accordingly, closer needle-to-PTFE disc distance, positive charging mode and thinner PTFE disc provided a better PTFE surface potential uniformity. However, the effects of PTFE charge polarity and needle distance on the electrostatic charge potential uniformity were much more remarkable in comparison with the effects of PTFE thickness. Additionally, the surface potential distribution profiles of charged PTFE discs were totally flat and independent of the PTFE thickness at 5- and 13-[Formula: see text]mm needle distances for the negative and positive charging modes, respectively. At the optimized charging conditions, large-area PTFE electret disc (0.5-mm-thick) with positive uniform surface charge potential especially at the edges up to [Formula: see text] 1.8[Formula: see text]kV with stability up to 77 days studied was produced by applying a new multiple heat treatment protocol to the PTFE disc for radon dosimetry. As also observed in this study, the sensitivity of PTFE electret dosimeters to a defined radon gas concentration increases as the PTFE thickness increases. Meanwhile, 0.5-mm-thick PTFE electret disc produced was selected to be used as a high quality electret dosimeter with acceptable and superior parameters for different applications in particular medium-term radiation dosimetry in both low and high dose rate ionizing radiation fields.

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Amer, Hany, Mostafa Elashmawy, Huda Alazab, and El-Din Ezz. "Suitability of pure nano crystalline LiF as a TLD dosimeter for high dose gamma radiation." Nuclear Technology and Radiation Protection 33, no. 1 (2018): 93–99. http://dx.doi.org/10.2298/ntrp1801093a.

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LiF is an alkali halide that is commonly used in radiation dosimetry utilizing its well-known thermoluminescence property. Pure LiF has very limited use in radiation dosimetry since the density and types of the internal traps are limited. For that reason, LiF is usually doped with different elements such as Mg and Ti in (TLD-100) to enhance its thermoluminescence properties and to be suitable for dosimetry applications. In this work we used ball milling as an alternative to dopants (impurities) to induce structure defects (e.g. dislocation) that will play the major role in thermoluminescence process similar to defectsecaused by dopants. The dislocation density of 1 h ball milled pristine LiF was evaluated at the MCX beamline of the Italian Synchrotron ELETTRA. A ball milled LiF was then compressed in the form of chips, then annealed for 1 h at 600?C to get rid of low temperature dislocations. The annealed samples showed linear response in the range 50-300 Gy. Fading investigation showed that the integral thermoluminescence intensity almost stabilizes after 12 days from the first irradiation. Results indicate that ball milling is a new promising technique to produce thermoluminescence dosimeters without using any kind of dopants.

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Hashimoto, Tetsuo. "An Overview of Red-Thermoluminescence (RTL) Studies on Heated Quartz and RTL Application to Dosimetry and Dating." Geochronometria 30, no. -1 (January 1, 2008): 9–16. http://dx.doi.org/10.2478/v10003-008-0011-z.

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An Overview of Red-Thermoluminescence (RTL) Studies on Heated Quartz and RTL Application to Dosimetry and DatingThe RTL-phenomena in quartz grains were initially reported and their properties and applications were developed by our group. Although RTL-measurements had the difficulty of overcoming high background counts due to blackbody radiation, the excellent dose linearity and hard-to-bleaching nature of quartz RTL are suitable for accurate retrospective dosimetry and dating of burnt archaeological materials. In his paper, the discovery of RTL-phenomena is described. Subsequently, the construction and features of an automatic luminescence measuring system are mentioned together with innovative methods of decreasing the background level for the RTL measurement. Practical applications to dosimetry and dating are then described from the viewpoints of the preferable nature of RTL in comparison to other luminescence observations. Finally, some recent advances in RTL research are presented based on their emission mechanism correlated with impurity contents.

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Anvari, Akbar, Seyed Mahmoud Reza Aghamiri, Seyed Rabi Mahdavi, Parham Alaei, and Mohammad Mohammadi. "Dosimetric properties of fluoroscopic EPID for transit dosimetry." Journal of Radiotherapy in Practice 14, no. 1 (October 30, 2014): 27–34. http://dx.doi.org/10.1017/s1460396914000405.

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AbstractThe aim of this work was to evaluate dose response of fluoroscopic EPID for transit dosimetry applications. Properties studied included warm up time, build-up thickness evaluation, dose history, linearity, stability, and short and long-term reproducibility of EPID response, as well as field size dependence.Pixel value matrices of electronic portal images in DICOM format were analysed in central and 8 off axis points using customised written codes in Matlab. In order to do this, nine 26×26 pixel matrices were selected as regions of interest, the regions represented by these arrays were 1×1 and 0·65×0·65 cm2 at the EPID and isocentre level, respectively.Necessary warm up time for stable operation of EPID is 30 minutes, and there is no need for extra build-up layer to increase the dose response. Linearity tests indicate charged coupled device camera of EPID saturates at 50 cGy level, and does not have linear relationship with dose. Reproducibility and stability of the measurements were excellent and the detector showed same signal with a maximum deviation of <0·3% both in short and long terms. Results of dosimetric evaluation have shown the TheraView fluoroscopic EPID can be used for transit dosimetry purposes.

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Scuderi, Valentina, Antonino Amato, Antonio Amico, Marco Borghesi, Giuseppe Cirrone, Giacomo Cuttone, Antonin Fajstavr, et al. "Diagnostics and Dosimetry Solutions for Multidisciplinary Applications at the ELIMAIA Beamline." Applied Sciences 8, no. 9 (August 21, 2018): 1415. http://dx.doi.org/10.3390/app8091415.

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ELI (Extreme Light Infrastructure) multidisciplinary applications of laser-ion acceleration (ELIMAIA) is one the user facilities beamlines of the ELI-Beamlines facility in Prague. It will be dedicated to the transport of laser-driven ion beams and equipped with detectors for diagnostics and dosimetry, in order to carry out experiments for a broad range of multidisciplinary applications. One of the aims of the beamline is also to demonstrate the feasibility of these peculiar beams for possible medical applications, which means delivering controllable and stable beams, properly monitoring their transport parameters and accurately measuring the dose per shot. To fulfil this task, innovative systems of charged particle beam diagnostics have been realized and alternative approaches for relative and absolute dosimetry have been proposed. Concerning the first one, real-time diagnostic solutions have been adopted, involving the use of time-of-flight techniques and Thomson parabola spectrometry for an on-line characterization of the ion beam parameters, as well as radiochromic films, nuclear track detectors (typically CR39), and image plates for single shot measurements. For beam dosimetry, real-time beam/dose monitoring detectors have been realized, like the secondary emission monitor and a double-gap ionization chamber, which can be cross calibrated against a Faraday cup, used for absolute dosimetry. The main features of these detectors are reported in this work together with a description of their working principle and some preliminary tests.

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Fragopoulou, M., S. Stoulos, M. Zamani, E. Benton, D. O'Sullivan, S. Siskos, T. Laopoulos, V. Konstantakos, and G. Sarrabayrouse. "A study of the response of depleted type p-MOSFETs to electron dose." HNPS Proceedings 21 (March 8, 2019): 84. http://dx.doi.org/10.12681/hnps.2009.

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The p-MOSFET dosimeter studied in this work has been manufactured at LAAS- CNRS Laboratory in Toulouse France, for applications in personal and space dosimetry. They are proposed for proton, heavy ions and electron and photon dose measurements. The current study investigates the sensitivity of this new type of Metal-Oxide-Semiconductor field effect transistor (MOSFET) to electrons. The sensitivity of the new MOSFET based dosemeters to electrons is linear for wide dose ranges. The influence of the electrons energy on the dosemeters response is also investigated.

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Hladik, Daniela, Martin Bucher, David Endesfelder, and Ursula Oestreicher. "The Potential of Omics in Biological Dosimetry." Radiation 2, no. 1 (January 17, 2022): 78–90. http://dx.doi.org/10.3390/radiation2010006.

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Biological dosimetry is an internationally recognized method for quantifying and estimating radiation dose following suspected or verified excessive exposure to ionising radiation. In severe radiation accidents where a large number of people are potentially affected, it is possible to distinguish irradiated from non-irradiated people in order to initiate appropriate medical care if necessary. In addition to severe incidents caused by technical failure, environmental disasters, military actions, or criminal abuse, there are also radiation accidents in which only one or a few individuals are affected in the frame of occupational or medical exposure. The requirements for biological dosimetry are fundamentally different for these two scenarios. In particular, for large-scale radiation accidents, pre-screening methods are necessary to increase the throughput of samples for a rough first-dose categorization. The rapid development and increasing use of omics methods in research as well as in individual applications provides new opportunities for biological dosimetry. In addition to the discovery and search for new biomarkers, dosimetry assays based on omics technologies are becoming increasingly interesting and hold great potential, especially for large-scale dosimetry. In the following review, the different areas of biological dosimetry, the problems in finding suitable biomarkers, the current status of biomarker research based on omics, the potential applications of assays using omics technologies, and also the limitations for the different areas of biological dosimetry are discussed.

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Méndez, Ignasi, Juan José Rovira-Escutia, and Bozidar Casar. "A protocol for accurate radiochromic film dosimetry using Radiochromic.com." Radiology and Oncology 55, no. 3 (August 10, 2021): 369–78. http://dx.doi.org/10.2478/raon-2021-0034.

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Abstract Background Radiochromic films have many applications in radiology and radiation therapy. Generally, the dosimetry system for radiochromic film dosimetry is composed of radiochromic films, flatbed scanner, and film analysis software. The purpose of this work is to present the effectiveness of a protocol for accurate radiochromic film dosimetry using Radiochromic.com as software for film analysis. Materials and methods Procedures for image acquisition, lot calibration, and dose calculation are explained and analyzed. Radiochromic.com enables state-of-the-art models and corrections for radiochromic film dosimetry, such as the Multigaussian model for multichannel film dosimetry, and lateral, inter-scan, and re-calibration corrections of the response. Results The protocol presented here provides accurate dose results by mitigating the sources of uncertainty that affect radiochromic film dosimetry. Conclusions Appropriate procedures for film and scanner handling in combination with Radiochromic.com as software for film analysis make easy and accurate radiochromic film dosimetry feasible.

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Pathan, Suhana, Prachi Dubey, Prachi Tadge, and Sudeshna Ray. "A Comprehensive Review on Rare-Earth Based Thermoluminescence Phosphors for Radiation Dosimetry." ECS Transactions 107, no. 1 (April 24, 2022): 20073–84. http://dx.doi.org/10.1149/10701.20073ecst.

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When ionizing radiation is incident on an insulating crystal, some of the deposited energy is stored in the lattice at defect sites, colour centres, etc. Upon heating the crystal, this stored energy is released and a fraction of it may be emitted as visible light. This is called ‘Thermoluminescence.’ Within certain limitations, the amount of light emitted is proportional to the radiation dose previously absorbed by the TL material. The application of thermoluminescence (TL) as a methodology for radiation dosimetry of ionizing radiation has been well-established since several decades and has found number of practical applications in various fields, such as personnel and environmental monitoring, retrospective dosimetry, medical dosimetry, space dosimetry, high-dose dosimetry, etc. Especially, alkaline-earth silicates are appropriate compounds as radiation detectors due to their high chemical stability. Doping may either cause the formation of new defect centers or recovering of existing levels within the band-gap for a defective host which changes both the optical and electronic features of the materials. Therefore, it is of great importance by choosing both the dopant as well as the host for thermoluminescence application. It has already been reported that commercially available thermoluminescence phosphor suffers from fading, stability, etc., which justifies the ongoing need to identify factors that can be exploited to make a thermoluminescence phosphor with high efficiency and stability.

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García-Haro, A. R., R. Bernal, C. Cruz-Vázquez, S. E. Burruel-Ibarra, V. R. Orante-Barrón, and F. Brown. "Study of the Thermoluminescent Characteristics of Ceramic Roof Tiles Exposed to Beta Radiation." MRS Proceedings 1481 (2012): 89–95. http://dx.doi.org/10.1557/opl.2012.1636.

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ABSTRACTIn this work, thermoluminescence (TL) characteristics of roof tile ceramic samples previously exposed to beta radiation are reported for the very first time. TL measurements were carried out using powdered samples obtained by the the fine-grained method, with grain size ranged from 300 nm to 5 μm. Characteristic thermoluminescence glow curves showed a complex structure with a dosimetric maximum located at ~ 200 °C. TL response of roof tile samples increases as the radiation dose increases in the 25 Gy to 1.6 kGy range. One response showed a linear behaviour, with no evidence of saturation within the dose interval investigated. The entire TL glow curve exhibited a remarkable reusability during 10 consecutive irradiation-TL readout cycles. The total TL signal showed a very low fading and remained almost constant after 3 h of irradiation and the corresponding TL readout. TL dosimetry features of powdered roof tile place it as a promising material in retrospective dosimetry as well as in possible TL dating applications.

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De la Garza-Ramos, Cynthia, and Beau B. Toskich. "Radioembolization for the Treatment of Hepatocellular Carcinoma: The Road to Personalized Dosimetry and Ablative Practice." Seminars in Interventional Radiology 38, no. 04 (October 2021): 466–71. http://dx.doi.org/10.1055/s-0041-1735571.

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AbstractRadioembolization dosimetry for the treatment of hepatocellular carcinoma has evolved alongside our understanding of best practice for this therapy. At the core of advances in dosimetry are personalized and ablative applications of radioembolization, which have generated paradigm shifts in both safety and efficacy. This review provides a summary of fundamental radioembolization dosimetry concepts and narrates how our approach to treating patients has shifted from conventional to tailored and definitive therapy.

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Knežević, Ž., N. Beck, Đ. Milković, S. Miljanić, and M. Ranogajec-Komor. "Characterisation of RPL and TL dosimetry systems and comparison in medical dosimetry applications." Radiation Measurements 46, no. 12 (December 2011): 1582–85. http://dx.doi.org/10.1016/j.radmeas.2011.05.042.

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Oliver, P. A. K., and Rowan M. Thomson. "Cavity theory applications for kilovoltage cellular dosimetry." Physics in Medicine and Biology 62, no. 11 (May 5, 2017): 4440–59. http://dx.doi.org/10.1088/1361-6560/aa6a42.

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Journal articles on the topic 'Dosimetry applications'

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