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Sample records for fields dosimetry biokinetics

  1. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Executive summary

    International Nuclear Information System (INIS)

    Jacob, P.; Paretzke, H.G.; Roth, P.

    2000-01-01

    The Association Contract covers a range of research domains that are important to the Radiation Protection Research Action, especially in the areas 'Evaluation of Radiation Risks' and 'Understanding Radiation Mechanisms and Epidemiology'. Three research projects concentrate on radiation dosimetry research and two projects on the modelling of radiation carcinogenesis. The following list gives an overview on the topics and responsible scientific project leaders of the Association Contract: Study of radiation fields and dosimetry at aviation altitudes. Biokinetics and dosimetry of incorporated radionuclides. Dose reconstruction. Biophysical models for the induction of cancer by radiation. Experimental data for the induction of cancer by radiation of different qualities. (orig.)

  2. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Biokinetics and dosimetry of incorporated radionuclides. Final report

    International Nuclear Information System (INIS)

    Roth, P.; Aubineau-Laniece, I.; Bailly-Despiney, I.

    2000-01-01

    The final report 'Biokinetics and Dosimetry of Incorporated Radionuclides' presented here is one part of the 5 individual reports. The work to be carried out within this project is structured into four Work Packages: Workpackage 1 concentrates on ingested radionuclides, considering doses to the GI tract and radionuclide absorption. A major objective is the development of a new dosimetric model of the GI tract, taking account of most recent data on gut transit and dose to sensitive cells. Workpackage 2 seeks to improve and extend biokinetic and dosimetric models for systemic radionuclides. Existing models for adults and children will be extended to other elements and new models will be developed for the embryo and fetus. Workpackage 3 is to improve assessment of localised distribution of dose within tissues at the cellular level for specific examples of Auger emitters and alpha emitting isotopes, in relation to observed effects. The work will include experimental studies of dose/effect relationship and the development of localisation methods. Workpackage 4 concerns the development of computer codes for the new dosimetric models, quality assurance of the models and the calculation of dose coefficients. Formal sensitivity analysis will be used to identify critical areas of model development and to investigate the effects of variability and incertainty in biokinetic parameters. (orig.)

  3. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P; Paretzke, H G; Roth, P [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Michael, B D [Mount Vernon Hospital, Northwood (United Kingdom). Gray Lab.; O` Sullivan, D [Dublin Inst. for Advanced Studies (Ireland)

    1999-12-31

    The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

  4. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.; Paretzke, H.G.; Roth, P. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Michael, B.D. [Mount Vernon Hospital, Northwood (United Kingdom). Gray Lab.; O`Sullivan, D. [Dublin Inst. for Advanced Studies (Ireland)

    1998-12-31

    The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

  5. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

    International Nuclear Information System (INIS)

    Jacob, P.; Paretzke, H.G.; Roth, P.

    1998-01-01

    The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

  6. Biokinetics and dosimetry of radioactively labelled organic C-14 compounds

    International Nuclear Information System (INIS)

    Krins, A.; Sahre, P.; Schoenmuth, T.

    2003-12-01

    The report starts with summarising research work and the resulting scientific information in connection with the dosimetry of C-14 labelled organic compounds. Biokinetic models are developed for compounds such as benzene, phenol, aniline, nitrobenzene, and a selection of pharmaceuticals, in order to show the radioactivity distribution after administration of the C-14 labelled substances. Based on the those models, dose coefficients and excretion rates are derived. The following synoptic view of the available data library leads on to a discussion of various aspects, as eg. the question of whether and how monitoring for detection of incorporation of C-14 administered with labelled organic compounds is possible. None of the questions and aspects arising in connection with this subject can be adequately dealt with in the present document, but concepts and methods are presented which permit an interpretation of radioactivity excretion data measured after incorporation of C-14 labelled organic substances. (orig./CB) [de

  7. Biokinetics and internal dosimetry of inhaled metal tritide particles

    Science.gov (United States)

    Wang, Yansheng

    1998-12-01

    Metal tritides (MT), stable chemical compounds of tritium, are widely used in nuclear engineering facilities. MT particles can be released as aerosols. Inhaling MT particles is a potential occupational radiation hazard. Little information is available on their dissolution behavior, biokinetics, and dosimetry. The objectives of present dissertation are to estimate dissolution rates, to develop biokinetic models, to improve internal dosimetric considerations, and to classify MT materials. This study consisted of three phases: In vitro dissolution in a simulated lung fluid, In vivo rat experiments on retention and clearance, and biokinetic modeling and dosimetric evaluation. There was a supporting study on self- absorption of tritium beta in MT particles. MT materials used in this study were titanium (Ti) and zirconium (Zr) tritides. Results shows considerable self-absorption of beta particles and their energy, even for respirable MT particles smaller than 5 μm. The self-absorption factors should be required for counting MT particle samples and for estimating absorbed dose to tissues. In vitro and in vivo dissolution data indicate that Ti and Zr tritides are poorly soluble materials. Ti tritide belongs to the W class or M type while Zr tritide can be classified as Y class or S type. Due to long retention time of the MT particles, tritium betas directly from the particles contribute over 90% of the absorbed dose to lung. The lung dose contributes most of the effective dose to the whole body. Dissolved tritium including tritiated water (HTO) and organically bound tritium (OBT) has less effect on the lung dose and effective dose. Results on the annual limit on intake (ALI) indicate that the current radiation protection guideline based on HTO is not adequate for inhalation exposure to MT particles and needs to be modified. The biokinetic models developed in this study have predictive powers to estimate the consequences of a human inhalation exposure to MT aerosols. The

  8. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Biophysical models for the induction of cancer by radiation. Final report

    International Nuclear Information System (INIS)

    Paretzke, H.G.; Ballarini, F.; Brugmans, M.

    2000-01-01

    The overall project is organised into seven work packages. WP1 concentrates on the development of mechanistic, quantitative models for radiation oncogenesis using selected data sets from radiation epidemiology and from experimental animal studies. WP2 concentrates on the development of mechanistic, mathematical models for the induction of chromosome aberrations. WP3 develops mechanistic models for radiation mutagenesis, particularly using the HPRT-mutation as a paradigm. WP4 will develop mechanistic models for damage and repair of DNA, and compare these with experimentally derived data. WP5 concentrates on the improvement of our knowledge on the chemical reaction pathways of initial radiation chemical species in particular those that migrate to react with the DNA and on their simulation in track structure codes. WP6 models by track structure simulation codes the production of initial physical and chemical species, within DNA, water and other components of mammalian cells, in the tracks of charged particles following the physical processes of energy transfer, migration, absorption, and decay of excited states. WP7 concentrates on the determination of the start spectra of those tracks considered in WP6 for different impinging radiation fields and different irradiated biological objects. (orig.)

  9. A physiological biokinetic model for the [7(N)-{sup 3}H]-cholesterol dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Adriano dos Santos; Martins, Joao Francisco Trencher; Velo, Alexandre Franca; Hamada, Margarida M.; Mesquita, Carlos Henrique de, E-mail: adriano_oliveira@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Cardiovascular diseases (CVD) are a major source of deaths worldwide according to WHO (World Health Organization). It is well-known that the change of the level of plasma lipoproteins, which are responsible for the cholesterol transport in the bloodstream, is a main cause of these diseases. For this reason, to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deepen the understanding of associated diseases. The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose, due to the intake of [7(N){sup -3}H] –Cholesterol in physiological issues, in metabolic studies. The internal dosimetry is important to know the biological effects of radiation. The model was based on Schwartz et al (2004), using parameters for the plasmatic lipoproteins and ICRP 30 (1979) gastrointestinal tract; the dose in the compartments were calculated using the MIRD methodology and the compartmental analysis by Matlab® software. The coefficients were estimated for an adult phantom with a body mass of 73.3 kg. (author)

  10. A physiological biokinetic model for the [7(N)-3H]-cholesterol dosimetry

    International Nuclear Information System (INIS)

    Oliveira, Adriano dos Santos; Martins, Joao Francisco Trencher; Velo, Alexandre Franca; Hamada, Margarida M.; Mesquita, Carlos Henrique de

    2015-01-01

    Cardiovascular diseases (CVD) are a major source of deaths worldwide according to WHO (World Health Organization). It is well-known that the change of the level of plasma lipoproteins, which are responsible for the cholesterol transport in the bloodstream, is a main cause of these diseases. For this reason, to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deepen the understanding of associated diseases. The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose, due to the intake of [7(N) -3 H] –Cholesterol in physiological issues, in metabolic studies. The internal dosimetry is important to know the biological effects of radiation. The model was based on Schwartz et al (2004), using parameters for the plasmatic lipoproteins and ICRP 30 (1979) gastrointestinal tract; the dose in the compartments were calculated using the MIRD methodology and the compartmental analysis by Matlab® software. The coefficients were estimated for an adult phantom with a body mass of 73.3 kg. (author)

  11. A review of contributions of human tissue studies to biokinetics, bio-effects and dosimetry of plutonium in man

    International Nuclear Information System (INIS)

    Kathren, R. L.

    2004-01-01

    This paper briefly reviews the contributions made by human tissue studies to improved understanding of the biokinetics, dosimetry and potential bio-effects of plutonium in man. It includes consideration of tissue donations from both environmental and occupational populations, along with a brief history of human experience with plutonium and consideration of the bio-ethical aspects of post-mortem human tissue sampling. (authors)

  12. Biokinetics and dosimetry of target-specific radiopharmaceuticals for molecular imaging and therapy

    International Nuclear Information System (INIS)

    Ferro F, G.; Torres G, E.; Gonzalez V, A.; Murphy, C.A. de

    2006-01-01

    Molecular imaging techniques directly or indirectly monitor and record the spatiotemporal distribution of molecular or cellular processes for biochemical, biologic, diagnostic or therapeutic applications. 99m Tc-HYNlC-TOC has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. Therapies using radiolabeled anti-CD20 have demonstrated their efficacy in patients with B-cell non Hodgkin's Iymphoma (NHL). The aim of this study was to establish biokinetic models for 99m Tc-HYNlC-TOC and 188 Re-anti-CD20 prepared from Iyophilized kits, and to evaluate their dosimetry as target-specific radiopharmaceuticals. Whole-body images were acquired at different times after 99m Tc-HYNlC-TOC or 188 Re-anti-CD20 administration obtained from instant freeze-dried kit formulations with radiochemical purities > 95 %. Regions of interest (ROls) were drawn around source organs on each time frame. The cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate time-activity curves in each organ, to adjust the biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. 99m Tc-HYNlC-TOC images showed an average tumor/blood (heart) ratio of 4.3 ± 0.7 in receptor-positive tumors at 1 h and the mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv. Results showed that after administration of 7 GBq of 188 Re-anti-CD20 the absorbed dose to whole body would be 0.7 Gy (0.1 mGy/MBq) which is the indicated dose for non Hodgkin's Iymphome therapies. (Author)

  13. INDOSE V2.1.1, Internal Dosimetry Code Using Biokinetics Models

    International Nuclear Information System (INIS)

    Silverman, Ido

    2002-01-01

    A - Description of program or function: InDose is an internal dosimetry code developed to enable dose estimations using the new biokinetic models (presented in ICRP-56 to ICRP71) as well as the old ones. The code is written in FORTRAN90 and uses the ICRP-66 respiratory tract model and the ICRP-30 gastrointestinal tract model as well as the new and old biokinetic models. The code has been written in such a way that the user is able to change any of the parameters of any one of the models without recompiling the code. All the parameters are given in well annotated parameters files that the user may change and the code reads during invocation. As default, these files contains the values listed in ICRP publications. The full InDose code is planed to have three parts: 1) the main part includes the uptake and systemic models and is used to calculate the activities in the body tissues and excretion as a function of time for a given intake. 2) An optimization module for automatic estimation of the intake for a specific exposure case. 3) A module to calculate the dose due to the estimated intake. Currently, the code is able to perform only its main task (part 1) while the other two have to be done externally using other tools. In the future we would like to add these modules in order to provide a complete solution for the people in the laboratory. The code has been tested extensively to verify the accuracy of its results. The verification procedure was divided into three parts: 1) verification of the implementation of each model, 2) verification of the integrity of the whole code, and 3) usability test. The first two parts consisted of comparing results obtained with InDose to published results for the same cases. For example ICRP-78 monitoring data. The last part consisted of participating in the 3. EIE-IDA and assessing some of the scenarios provided in this exercise. These tests where presented in a few publications. It has been found that there is very good agreement

  14. 99mTc-exendin(9-39)/octreotide: biokinetics and radiation dosimetry in healthy individuals.

    Science.gov (United States)

    Ocampo-García, Blanca E; Santos-Cuevas, Clara L; Luna-Gutiérrez, Myrna A; Ignacio-Alvarez, Eleazar; Pedraza-López, Martha; Manzano-Mayoral, Cesar

    2017-11-01

    About 90% of insulinomas are benign and 5-15% are malignant. Benign insulinomas express the glucagon-like peptide-1 receptor (GLP-1R, which recognizes exendin-4 and low levels of the somatostatin receptor (SSTR, which recognizes octreotide), whereas malignant insulinomas overexpress SSTR and low levels of GLP-1R. Recently, Lys(Tc-EDDA/HYNIC)-exendin(9-39)/Tc-EDDA/HYNIC-Tyr-octreotide was formulated to detect 100% of insulinomas. The aim of this study was to estimate the biokinetics and dosimetry of Tc-exendin(9-39)/octreotide in four healthy individuals. Tc-exendin(9-39)/octreotide was obtained from a lyophilized formulation with radiochemical purities of more than 97%, determined by reversed-phase high-performance liquid chromatography. Whole-body images from four healthy individuals were acquired at 20 min, 2, 6, and 24 h after Tc-exendin(9-39)/octreotide administration. Regions of interest were drawn around the source organs on each time frame. Each region of interest was corrected by background, attenuation, scattered radiation, and physical decay. The image sequence was used to extrapolate the Tc-exendin(9-39)/octreotide time-activity curves of each organ to adjust the biokinetic model and calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation doses. Furthermore, in a patient suspicious of harboring an insulinoma, whole-body single-photon emission computed tomography/computed tomography images were obtained at 3 h. For four healthy individuals, the blood activity showed a half-life value of 1.20 min for the fast component (T1/2 α=ln 2/34.71), 8.7 min for the first slow component (T1/2 β=ln 2/4.76), and 1.7 h for the second slow component (T1/2 γ=ln 2/0.401). The average equivalent doses calculated for a study using 555 MBq were 15.10, 4.13, 3.08, 2.61, and 1.90 mSv for the kidneys, upper large intestinal wall, lower large

  15. Reliability of a new biokinetic model of zirconium in internal dosimetry: part I, parameter uncertainty analysis.

    Science.gov (United States)

    Li, Wei Bo; Greiter, Matthias; Oeh, Uwe; Hoeschen, Christoph

    2011-12-01

    The reliability of biokinetic models is essential in internal dose assessments and radiation risk analysis for the public, occupational workers, and patients exposed to radionuclides. In this paper, a method for assessing the reliability of biokinetic models by means of uncertainty and sensitivity analysis was developed. The paper is divided into two parts. In the first part of the study published here, the uncertainty sources of the model parameters for zirconium (Zr), developed by the International Commission on Radiological Protection (ICRP), were identified and analyzed. Furthermore, the uncertainty of the biokinetic experimental measurement performed at the Helmholtz Zentrum München-German Research Center for Environmental Health (HMGU) for developing a new biokinetic model of Zr was analyzed according to the Guide to the Expression of Uncertainty in Measurement, published by the International Organization for Standardization. The confidence interval and distribution of model parameters of the ICRP and HMGU Zr biokinetic models were evaluated. As a result of computer biokinetic modelings, the mean, standard uncertainty, and confidence interval of model prediction calculated based on the model parameter uncertainty were presented and compared to the plasma clearance and urinary excretion measured after intravenous administration. It was shown that for the most important compartment, the plasma, the uncertainty evaluated for the HMGU model was much smaller than that for the ICRP model; that phenomenon was observed for other organs and tissues as well. The uncertainty of the integral of the radioactivity of Zr up to 50 y calculated by the HMGU model after ingestion by adult members of the public was shown to be smaller by a factor of two than that of the ICRP model. It was also shown that the distribution type of the model parameter strongly influences the model prediction, and the correlation of the model input parameters affects the model prediction to a

  16. Reliability of a new biokinetic model of zirconium in internal dosimetry: part II, parameter sensitivity analysis.

    Science.gov (United States)

    Li, Wei Bo; Greiter, Matthias; Oeh, Uwe; Hoeschen, Christoph

    2011-12-01

    The reliability of biokinetic models is essential for the assessment of internal doses and a radiation risk analysis for the public and occupational workers exposed to radionuclides. In the present study, a method for assessing the reliability of biokinetic models by means of uncertainty and sensitivity analysis was developed. In the first part of the paper, the parameter uncertainty was analyzed for two biokinetic models of zirconium (Zr); one was reported by the International Commission on Radiological Protection (ICRP), and one was developed at the Helmholtz Zentrum München-German Research Center for Environmental Health (HMGU). In the second part of the paper, the parameter uncertainties and distributions of the Zr biokinetic models evaluated in Part I are used as the model inputs for identifying the most influential parameters in the models. Furthermore, the most influential model parameter on the integral of the radioactivity of Zr over 50 y in source organs after ingestion was identified. The results of the systemic HMGU Zr model showed that over the first 10 d, the parameters of transfer rates between blood and other soft tissues have the largest influence on the content of Zr in the blood and the daily urinary excretion; however, after day 1,000, the transfer rate from bone to blood becomes dominant. For the retention in bone, the transfer rate from blood to bone surfaces has the most influence out to the endpoint of the simulation; the transfer rate from blood to the upper larger intestine contributes a lot in the later days; i.e., after day 300. The alimentary tract absorption factor (fA) influences mostly the integral of radioactivity of Zr in most source organs after ingestion.

  17. Biokinetics and dosimetry in patients of 99mTc-EDDA/HYNIC-Tyr3-octreotide prepared from lyophilized kits.

    Science.gov (United States)

    González-Vázquez, Armando; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Gutiérrez-García, Zohar

    2006-07-01

    99mTc-EDDA/HYNIC-Tyr3-octreotide (99mTc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for 99mTc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after 99mTc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99mTc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3+/-0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv.

  18. Biokinetics and dosimetry in patients of 99mTc-EDDA/HYNIC-Tyr3-octreotide prepared from lyophilized kits

    International Nuclear Information System (INIS)

    Gonzalez-Vazquez, Armando; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Gutierrez-Garcia, Zohar

    2006-01-01

    99m Tc-EDDA/HYNIC-Tyr 3 -octreotide ( 99m Tc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for 99m Tc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after 99m Tc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3±0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv

  19. Biokinetics aand dosimetry of inhaled 238PuO2 in the beagle dog: An update

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Griffith, W.C.; Diel, J.H.

    1994-01-01

    The temporal and spatial distributions of 238 Pu have been measured during the course of a dose-response study of the biological effects of inhaled 238 PuO 2 in Beagle dogs. These measurements were done on the dose-response study animals, as well as a separate group of dogs exposed to similar aerosols and killed serially out to 4 y after exposure. The data from this latter group provided the basis for the development of a biokinetic/dosimetric model for 238 PuO 2 in dogs. Since the publication of this model, several important findings have been made that affected the dosimetric evaluations. The first involved the discovery of significant quantities of natural uranium (U) in the feces samples. The U was measured with the plutonium (Pu), which inflated the values for purported Pu in feces. The second finding involved the addition of Pu biokinetics data from the dose-response dogs, which increased the period of observation from 4 y to 15 y; these later data were not consistent with the earlier model predictions. The purpose of this investigation was (1) to remove the analytical bias in the 238 Pu radiochemical data due to the U and (2) to modify the original model of Mewhinney and Diel, taking into account all data from both studies

  20. Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images.

    Science.gov (United States)

    Leal Neto, Viriato; Vieira, José Wilson; Lima, Fernando Roberto de Andrade

    2014-01-01

    This article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. A software called DoRadIo (Dosimetria das Radiações Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C# programming language. With the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. The user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity.

  1. Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images*

    Science.gov (United States)

    Leal Neto, Viriato; Vieira, José Wilson; Lima, Fernando Roberto de Andrade

    2014-01-01

    Objective This article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and Methods A software called DoRadIo (Dosimetria das Radiações Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C# programming language. Results With the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion The user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. PMID:25741101

  2. Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images

    International Nuclear Information System (INIS)

    Leal Neto, Viriato; Vieira, Jose Wilson; Lima, Fernando Roberto de Andrade

    2014-01-01

    Objective: this article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and methods: a software called DoRadIo (Dosimetria das Radiacoes Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C ⧣ programming language. Results: with the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion: the user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. (author)

  3. Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images

    Energy Technology Data Exchange (ETDEWEB)

    Leal Neto, Viriato, E-mail: viriatoleal@yahoo.com.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Recife, PE (Brazil); Vieira, Jose Wilson [Universidade Federal de Pernambuco (UPE), Recife, PE (Brazil); Lima, Fernando Roberto de Andrade [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2014-09-15

    Objective: this article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and methods: a software called DoRadIo (Dosimetria das Radiacoes Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C ⧣ programming language. Results: with the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion: the user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. (author)

  4. Biokinetics and dosimetry of {sup 111}In-DOTA-NOC-ATE compared with {sup 111}In-DTPA-octreotide

    Energy Technology Data Exchange (ETDEWEB)

    Boubaker, Ariane; Prior, John O.; Champendal, Melanie; Bischof Delaloye, Angelika [Lausanne University Hospital, CHUV, Department of Nuclear Medicine, Lausanne (Switzerland); Willi, Jean-Pierre [University Hospital of Geneva, Department of Nuclear Medicine, Geneva 14 (Switzerland); Kosinski, Marek; Baechler, Sebastien [Lausanne University Hospital, Institute of Radiation Physics, Lausanne (Switzerland); Maecke, Helmut R. [University Hospital of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Ginj, Mihaela [University Health Network, Joint Department of Medical Imaging, Toronto, ON (Canada); Buchegger, Franz [Lausanne University Hospital, CHUV, Department of Nuclear Medicine, Lausanne (Switzerland); University Hospital of Geneva, Department of Nuclear Medicine, Geneva 14 (Switzerland)

    2012-12-15

    The biokinetics and dosimetry of {sup 111}In-DOTA-NOC-ATE (NOCATE), a high-affinity ligand of SSTR-2 and SSTR-5, and {sup 111}In-DTPA-octreotide (Octreoscan trademark, OCTREO) were compared in the same patients. Seventeen patients (10 men, 7 women; mean age 60 years), referred for an OCTREO scan for imaging of a neuroendocrine tumour (15), thymoma (1) or medullary thyroid carcinoma (1), agreed to undergo a second study with NOCATE. Whole-body anterior-posterior scans were recorded 0.5 (100 % reference scan), 4, 24 and 48 h (17 patients) and 120 h (5 patients) after injection. In 16 patients the OCTREO scan (178 {+-} 15 MBq) was performed 16 {+-} 5 days before the NOCATE scan (108 {+-} 14 MBq) with identical timing; 1 patient had the NOCATE scan before the OCTREO scan. Blood samples were obtained from 14 patients 5 min to 48 h after injection. Activities expressed as percent of the initial (reference) activity in the whole body, lung, kidney, liver, spleen and blood were fitted to biexponential or single exponential functions. Dosimetry was performed using OLINDA/EXM. Initial whole-body, lung and kidney activities were similar, but retention of NOCATE was higher than that of OCTREO. Liver and spleen uptakes of NOCATE were higher from the start (p < 0.001) and remained so over time. Whole-body activity showed similar {alpha} and {beta} half-lives, but the {beta} fraction of NOCATE was double that of OCTREO. Blood T{sub 1/2}{beta} for NOCATE was longer (19 vs. 6 h). As a result, the effective dose of NOCATE (105 {mu}Sv/MBq) exceeded that of OCTREO (52 {mu}Sv/MBq), and the latter result was similar to the ICRP 106 value of 54 {mu}Sv/MBq. Differential activity measurement in blood cells and plasma showed an average of <5 % of NOCATE and OCTREO attached to globular blood components. NOCATE showed a slower clearance from normal tissues and its effective dose was roughly double that of OCTREO. (orig.)

  5. Biokinetics and dosimetry of 99m Tc-EDDA/HYNIC-[Lys3]-bombesin in humans: imaging of GRP receptors

    International Nuclear Information System (INIS)

    Santos C, C.L.; Ferro F, G.; Murphy, C.A de; Cardena, E.; Pichardo R, P.

    2007-01-01

    Full text: Bombesin (BN) receptor subtype 2 (GRP-r) is over-expressed on various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently we reported the 99- mTc-EDDA/HYNIC-[Lys 3 ]-Bombesin ( 99m Tc-HYNIC-BN) complex as a new radiopharmaceutical with high stability in human serum, specific cell GRP-receptor binding and rapid internalization. The aim of this study was to evaluate the 99m Tc-HYNIC-BN biokinetics and dosimetry in 5-healthy and 3-breast cancer women. Whole-body images were acquired at 20, 90, 180 min and 24 h after 99m Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source' organs on each time frame. The same set of ROIs was used for all 8 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-BN time activity curves in each organ, to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed a rapid radiopharmaceutical blood clearance with predominantly renal excretion and minimal hepatobiliary elimination. 99m Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in breast cancer lesions and well differentiated from GRP-r expression in lungs and airways with normal GRP-r density (ratio 3:1). The equivalent doses for a study using 370 MBq were 7.38±1.68, 0.59±0.08, 2.07±0.60, 0.58±0.1, 0.75±0.09 and 0.43±0.07 mSv for kidneys, liver, lungs, ovaries, pancreas and red marrow respectively. The effective dose was 1.64±0.25 mSv which is comparable with the doses known for most of the 99m Tc radiopharmaceutical studies in nuclear medicine. (Author)

  6. Biokinetics and dosimetry in patients of 99mTc-HYNIC-Lys3-Bombesin: images of GRP receptors

    International Nuclear Information System (INIS)

    Santos C, C. L.

    2007-01-01

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [ 99m Tc]EDDA/HYNIC-Lys 3 -bombesin ( 99m Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using 99m Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after 99m Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. 99m Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red marrow). The mean effective dose

  7. Mixed field dosimetry with paired ionization chambers

    International Nuclear Information System (INIS)

    Coppola, M.; Porro, F.

    1977-01-01

    This report describes the results of neutron and gamma mixed-field dosimetry obtained by the Ispra Group in the framework of the European Neutron Dosimetry intercomparison Project (ENDIP). The experimental method and the formulation employed for the derivation of Kerma results are also present

  8. Biokinetics and dosimetry in patients of {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide prepared from lyophilized kits

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Vazquez, Armando [Departamento de Medicina Nuclear, Hospital Militar (Mexico); Facultad de Medicina, Universidad Autonoma del Estado de Mexico (Mexico); Ferro-Flores, Guillermina [Departamento de Materiales Radiactivos, Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico, C.P. 52045 (Mexico)]. E-mail: gff@nuclear.inin.mx; Arteaga de Murphy, Consuelo [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran (Mexico); Gutierrez-Garcia, Zohar [Departamento de Medicina Nuclear, Hospital Militar (Mexico)

    2006-07-15

    {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide ({sup 99m}Tc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for {sup 99m}Tc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3{+-}0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv.

  9. Biokinetics and dosimetry with 177Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

    Science.gov (United States)

    Rodríguez-Cortés, J.; de Murphy, C. Arteaga; Ferro-Flores, Ge; Pedraza-López, M.; Murphy-Stack, E.

    Malignant pancreatic tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to determine biokinetic parameters in mice, in order to estimate the induced pancreatic tumour absorbed doses and to evaluate an `in house' 177Lu-DOTA-TATE radiopharmaceutical as part of preclinical studies for targeted therapy in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (nD22) to obtain biokinetic and dosimetric data of 177Lu-DOTA-TATE. The mean tumour uptake 2 h post injection was 14.76±1.9% I.A./g; kidney and pancreas uptake, at the same time, were 7.27±1.1% I.A./g (1.71±0.90%/organ) and 4.20±0.98% I.A./g (0.42±0.03%/organ), respectively. The mean absorbed dose to tumour, kidney and pancreas was 0.58±0.02 Gy/MBq; 0.23±0.01 Gy/MBq and 0.14±0.01 Gy/MBq, respectively. These studies justify further dosimetric estimations to ensure that 177Lu-DOTA-TATE will act as expected in humans.

  10. Advances in electron dosimetry of irregular fields

    International Nuclear Information System (INIS)

    Mendez V, J.

    1998-01-01

    In this work it is presented an advance in Electron dosimetry of irregular fields for beams emitted by linear accelerators. At present diverse methods exist which are coming to apply in the Radiotherapy centers. In this work it is proposed a method for irregular fields dosimetry. It will be allow to calculate the dose rate absorbed required for evaluating the time for the treatment of cancer patients. Utilizing the results obtained by the dosimetric system, it has been possible to prove the validity of the method describe for 12 MeV energy and for square field 7.5 x 7.5 cm 2 with percentile error less than 1 % . (Author)

  11. Individual Dosimetry for High Energy Radiation Fields

    International Nuclear Information System (INIS)

    Spurny, F.

    1999-01-01

    The exposure of individuals on board aircraft increased interest in individual dosimetry in high energy radiation fields. These fields, both in the case of cosmic rays as primary radiation and at high energy particle accelerators are complex, with a large diversity of particle types, their energies, and linear energy transfer (LET). Several already existing individual dosemeters have been tested in such fields. For the component with high LET (mostly neutrons) etched track detectors were tested with and without fissile radiators, nuclear emulsions, bubble detectors for both types available and an albedo dosemeter. Individual dosimetry for the low LET component has been performed with thermoluminescent detectors (TLDs), photographic film dosemeters and two types of electronic individual dosemeters. It was found that individual dosimetry for the low LET component was satisfactory with the dosemeters tested. As far as the high LET component is concerned, there are problems with both the sensitivity and the energy response. (author)

  12. 99mTc-labeled PSMA inhibitor: Biokinetics and radiation dosimetry in healthy subjects and imaging of prostate cancer tumors in patients.

    Science.gov (United States)

    Santos-Cuevas, Clara; Davanzo, Jenny; Ferro-Flores, Guillermina; García-Pérez, Francisco O; Ocampo-García, Blanca; Ignacio-Alvarez, Eleazar; Gómez-Argumosa, Edgar; Pedraza-López, Martha

    2017-09-01

    The prostate-specific membrane antigen (PSMA) is expressed in epithelial cells of the prostate and highly overexpressed in 95% of advanced prostate cancers. The aims of this study was to estimate the biokinetics and dosimetry of 99m Tc-EDDA/HYNIC-iPSMA ( 99m Tc-labeled PSMA inhibitor) in eight healthy subjects and evaluate its usefulness as a tumor-imaging agent in eight prostate cancer patients. 99m Tc-EDDA/HYNIC-iPSMA was obtained from a lyophilized formulation with radiochemical purities >98%, determined by reversed-phase HPLC and ITLC-SG analyses. Whole-body images from eight healthy subjects were acquired at 20min, and at 2, 6 and 24h after 99m Tc-EDDA/HYNIC-iPSMA administration. Regions of interest (ROIs) were drawn around the source organs on each time frame. Each ROI was corrected by background, attenuation, scattered radiation and physical decay. The image sequence was used to extrapolate the 99m Tc-EDDA/HYNIC-iPSMA time-activity curves of each organ to adjust the biokinetic model and calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation doses. In eight prostate cancer patients with histologically confirmed cancer, whole-body SPECT/CT images were obtained at 3h. The blood activity showed a half-life value of 4.98min for the fast component (T 1/2 α=ln2/8.34), 2.49h for the first slow component (T 1/2 β=ln2/0.278), and 9.24h for the second slow component (T 1/2 γ=ln2/0.076). Images from patients showed an average tumor/background ratio of 8.99±3.27 at 3h. The average equivalent doses calculated for a study using 740MBq were 3.80, 7.06, 9.69, 10.70, and 28.80mSv for the breast, spleen, salivary glands, liver, and kidneys respectively, with an effective dose of 3.42±0.78mSv. All the absorbed doses were comparable to those known for most of the 99m Tc studies. 99m Tc-EDDA/HYNIC-iPSMA obtained from kit formulations showed high tumor uptake in

  13. Whole body MR-PET: a new internal dosimetry method for radiation transport calculation from biokinetic model data

    International Nuclear Information System (INIS)

    Nunes, Ana; Alves, Francisco; Patrício, Miguel

    2014-01-01

    In order to ensure the safe usage of new radiopharmaceuticals in Positron Emission Tomography (PET), it is necessary to quantify the doses delivered to the organs and tissues within the patients’ bodies. A framework that allows estimating the dose delivered by PET has been established by the MIRD Committee [1, 2] and ICRP []. Although this covers the most important terms and concepts in Internal Radiation Dosimetry (IRD), it does not provide a detailed guide to assist in the development of a full dosimetric study. We discuss the development, implementation, assessment and validation of an accurate method for IRD studies of PET radiotracers.

  14. Biokinetics and radiation dosimetry of 14C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine 'breath tests' using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Gunnarsson, Mikael

    2002-08-01

    14 C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used 14 C-breath tests: 14 C-triolein (examination of fat malabsorption), urea (detection of Helicobacter pylori infection in the stomach), glycocholic acid and xylose (examination of bacterial overgrowth in the small intestine) by using the highly sensitive accelerator mass-spectrometry (AMS) technique. The AMS technique has been used to measure low 14 C concentrations in small samples of exhaled air, urine, faeces and tissue samples and has improved the base for the estimation of the absorbed dose to various organs and tissues and the effective dose to man. The high sensitivity of the AMS system has also made it possible to perform 14 C breath tests on patient groups which were earlier subject for restriction (e.g. small children). In summary, our results show that for adult patients - and in the case of 14 C-urea breath test also for children down to 3 years of age - the dose contributions are comparatively low, both described as organ doses and as effective doses. For adults, the latter is: 14 C-glycocholic acid - 0.4 mSv/MBq, 14 C-triolein - 0.3 mSv/MBq, 14 C-xylose - 0.1 mSv/MBq and 14 C-urea - 0.04 mSv/MBq. Thus, from a radiation protection point of view there is no reason for restrictions in using any of the 14 C-labelled radiopharmaceutical included in this work in the activities normally used (0.07-0.2 MBq for a 70 kg patient)

  15. Targeted imaging of gastrin-releasing peptide receptors with 99mTc-EDDA/HYNIC-[Lys3]-bombesin: biokinetics and dosimetry in women.

    Science.gov (United States)

    Santos-Cuevas, Clara L; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Pichardo-Romero, Pablo A

    2008-08-01

    The gastrin-releasing peptide receptor (GRP-R) is expressed in several normal human tissues and is overexpressed in various human tumors including breast, prostate, small-cell lung cancer and pancreatic cancer. Recently, 99mTc-EDDA/HYNIC-[Lys]-bombesin (99mTc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-R binding and rapid cell internalization. The aim of this study was to determine the biokinetics and dosimetry of 99mTc-HYNIC-BN and the feasibility of using this radiopharmaceutical to image GRP-R in four early breast cancer patients and seven healthy women. Whole-body images were acquired at 20, 90, 180 min, and 24 h after 99mTc-HYNIC-BN administration. The same regions of interest were drawn around source organs on each time frame and regions of interest were converted to activity (conjugate view counting method). The image sequence was used to extrapolate 99mTc-HYNIC-BN time-activity curves in each organ to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. 99mTc-HYNIC-BN had a rapid blood clearance with mainly renal excretion. No statistically significant differences (P>0.05) in the radiation-absorbed doses among cancer patients and healthy women were observed. The average equivalent doses (n=11) were 24.8+/-8.8 mSv (kidneys), 7.3+/-1.8 mSv (lungs), 6.5+/-4.0 mSv (breast), 2.0+/-0.3 mSv (pancreas), 1.6+/-0.3 mSv (liver), 1.2+/-0.2 mSv (ovaries), and 1.0+/-0.2 mSv (red marrow). The effective dose was 3.3+/-0.6 mSv. The images showed well-differentiated concentration of 99mTc-HYNIC-BN in cancer mammary tissue. All the absorbed doses were comparable with those known for most of the 99mTc studies. 99mTc-HYNIC-BN shows high tumor uptake in breasts with malignant tumors so it is a promising imaging radiopharmaceutical to target site-specific early breast cancer. The results obtained

  16. Biokinetics and dosimetry of {sup 99m} Tc-EDDA/HYNIC-[Lys{sup 3}]-bombesin in humans: imaging of GRP receptors

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C.L.; Ferro F, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Murphy, C.A de [INCMNSZ, 14000 Mexico D.F. (Mexico); Cardena, E.; Pichardo R, P. [Departamento de Medicina Nuclear, Oncologia Centro Medico Siglo XXI, Mexico D.F. (Mexico)

    2007-07-01

    Full text: Bombesin (BN) receptor subtype 2 (GRP-r) is over-expressed on various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently we reported the {sup 99-}mTc-EDDA/HYNIC-[Lys{sup 3}]-Bombesin ({sup 99m}Tc-HYNIC-BN) complex as a new radiopharmaceutical with high stability in human serum, specific cell GRP-receptor binding and rapid internalization. The aim of this study was to evaluate the {sup 99m}Tc-HYNIC-BN biokinetics and dosimetry in 5-healthy and 3-breast cancer women. Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source' organs on each time frame. The same set of ROIs was used for all 8 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time activity curves in each organ, to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed a rapid radiopharmaceutical blood clearance with predominantly renal excretion and minimal hepatobiliary elimination. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in breast cancer lesions and well differentiated from GRP-r expression in lungs and airways with normal GRP-r density (ratio 3:1). The equivalent doses for a study using 370 MBq were 7.38{+-}1.68, 0.59{+-}0.08, 2.07{+-}0.60, 0.58{+-}0.1, 0.75{+-}0.09 and 0.43{+-}0.07 mSv for kidneys, liver, lungs, ovaries, pancreas and red marrow respectively. The effective dose was 1.64{+-}0.25 mSv which is comparable with the doses known for most of the {sup 99m}Tc radiopharmaceutical studies in nuclear medicine. (Author)

  17. Field dosimetry on sterilization area of medical-hospitable materials

    International Nuclear Information System (INIS)

    Mariano, C.S.T.P.; Campos, L.L.

    1992-01-01

    The calcium sulfate doped with dysprosium, used in high dose dosimetry by electron paramagnetic resonance (EPR), is studied on field dosimetry for medical-hospitable materials sterilization. The calibration curves of EPR signal in function of absorbed dose in air and the thermal decay of EPR signal at room temperature are also presented. (C.G.C)

  18. Biokinetics of radionuclides and treatment of accidental intakes

    International Nuclear Information System (INIS)

    Taylor, D.M.; Stradling, G.N.; Menetrier, F.

    2003-01-01

    This paper describes the objectives and reviews the progress of EULEP Working Party 5, convened under the auspices of the European Union's Fifth Framework Programme, to 'cluster' two EU-supported contracts, Biokinetics and Dosimetry of Internal Contamination (BIODOS (EU Contract FIS5-1999-00214)) and Radionuclide Biokinetics Database (EULEP) ( RBDATA-EULEP (Concerted Action Contract FIS5-1999-00218), and two non-EU funded projects, Biokinetics of Radionuclides in Human Volunteers (RNHV (non-EU Funded Project) and Treatment of Accidental Intakes of Radionuclides (TAIR (part-funded by EULEP)). (author)

  19. Patient dosimetry improvements in longitudinal field MRI linear accelerators

    International Nuclear Information System (INIS)

    Oborn, B.M.; Metcalfe, P.E.; Butson, M.J.; Keall, P.

    2010-01-01

    Full text: Many studies exist of the often undesirable dosimetry changes in transverse field MRI-Linacs. Currently there are plans by different groups around the world to develop longitudinal MRT-Linac systems as dosimetry is potentially superior to transverse field sy tems. The objective of this study is to investigate via Monte Carlo simulations, the potential dosimetry improvements expected in lo gitudinal MRI-Linac designs over transverse field designs for advanced image-guided radiotherapy (IGRT). Geant4 Monte Carlo simulations have been performed of the dosimetry from a Varian 2100c 6 MV photon beam in lo gitudinal magnetic field typical of expected MRI-Linac designs. A 30 x 30 x 20 cm' phantom has been simulated in magnetic fields between 0 and 3 T. Beam profiles and skin dose calculations have been performed and compared with transverse field systems. Results The longitudinal magnetic field acts to reduce lateral dose spread in all locations within a patient. As well as this, the electron return effcct is absent. This equates to reductions in penumbral widths and reductions in skin dose. When compared with transverse field systems the dosimetry is superior. This will also allow for further reductions in trcatment margins as compared to transverse field MRI Linac designs.

  20. Computational methods in several fields of radiation dosimetry

    International Nuclear Information System (INIS)

    Paretzke, Herwig G.

    2010-01-01

    Full text: Radiation dosimetry has to cope with a wide spectrum of applications and requirements in time and size. The ubiquitous presence of various radiation fields or radionuclides in the human home, working, urban or agricultural environment can lead to various dosimetric tasks starting from radioecology, retrospective and predictive dosimetry, personal dosimetry, up to measurements of radionuclide concentrations in environmental and food product and, finally in persons and their excreta. In all these fields measurements and computational models for the interpretation or understanding of observations are employed explicitly or implicitly. In this lecture some examples of own computational models will be given from the various dosimetric fields, including a) Radioecology (e.g. with the code systems based on ECOSYS, which was developed far before the Chernobyl reactor accident, and tested thoroughly afterwards), b) Internal dosimetry (improved metabolism models based on our own data), c) External dosimetry (with the new ICRU-ICRP-Voxelphantom developed by our lab), d) Radiation therapy (with GEANT IV as applied to mixed reactor radiation incident on individualized voxel phantoms), e) Some aspects of nanodosimetric track structure computations (not dealt with in the other presentation of this author). Finally, some general remarks will be made on the high explicit or implicit importance of computational models in radiation protection and other research field dealing with large systems, as well as on good scientific practices which should generally be followed when developing and applying such computational models

  1. Biokinetics and dosimetry of a hybrid formulation of 9mTc-BN and 99mTc-RGD2 starting from optic images in a murine model

    International Nuclear Information System (INIS)

    Cornejo A, L. G.

    2015-01-01

    This work has the purpose of evaluate the biokinetics and absorbed dose of radiation of hybrid formulation 99m Tc-BN / 99m Tc-RGD 2 in a murine model by optical imaging techniques using the multimodal preclinical in vivo image system Xtreme. The used method were the 99m Tc-BN, 99m Tc-RGD 2 and 99m Tc-BN/ 99m Tc-RGD 2 formulas, with specific recognition for GRPr and the integrin s α(v)β(3) and α(v)β(5) respectively, was injected in the vein tail of three nude mousses with induce breast cancer tumors (cell line T-47-D), by the preclinical multimodal imaging system Xtreme (Bruker), optical images in different times was acquired (5, 10, 20 min, 2 and 24 h), using Images Processing Toolbox of MATLAB these images was transform from RGB format to gray scales and sectioned in five independent images corresponding to heart, kidneys, bladder and tumor areas. The intensity of each images was computed in counts per pixel, then those intensities was corrected for background, attenuation and scattering, using different factors for each phenomena previously calculated. Finally the activity values quantified vs time was fitted into a biokinetic model to obtain the disintegrations number and cumulate activities in each organ. With these data the radiation absorbed dose were calculated using MIRD methodology. Results: The number of disintegration and absorbed dose calculated in MBq h/MBq and mGy/MBq, of injected mouse with the 99m Tc-BN/ 99m Tc-RGD 2 formulation, was: 0.035 ± 0.65 E-02, 0.25 x 10 -5 ± 0.46 E-07; 0.393 ± 0.51 E-1, 2.85 E-05 ± 3.7 E-06; 0.306 ± 0.21 E-01, 2.11 E-05 ± 1.45 E-06 and 0.151 ± 0.19 E-01, 1.09 E-05 ± 1.42 E-06 , in heart, kidneys, bladder and tumor, respectively. The number of disintegration obtained in kidneys is comparable to those reported for Trinidad B. 2014 Conclusions: Our results demonstrated that using optical images and a code for image analyses development in MATLAB, could achieve comparable quantitative results as the conventional

  2. Mixed field dosimetry with the twin chamber technique

    International Nuclear Information System (INIS)

    Burger, G.; Maier, E.

    1974-04-01

    For the separate dosimetry of the neutron- and gamma-component in a mixed beam it is principally possible to use two ionization chambers with different ratios of neutron- to gamma sensitivity. Several authors proposed for this purpose the use of a homogenious TE-chamber filled with the TE-gas and of a carbon-chamber filled with CO 2 -gas. This chamber combination is also commercially available in several countries. The chambers are normally equipped with a continuous gas-flow provision and with a waterproof-housing for the use within liquid phantoms. The application of such chambers for mixed field dosimetry in the intercomparison project of the ICRU at the RARAF-facility in Brookhaven (International Neutron Dosimetry Intercomparison - INDI) is described. (orig./HP) [de

  3. Dosimetry of irregular shaped fields of β rays

    International Nuclear Information System (INIS)

    Supe, S.J.; Datta, S.

    1976-01-01

    The feasibility of using various shapes and sizes of field limiting devices and collimators with β-ray eye applicators has necessitated the study of dosimetry for these fields. A method of calculating surface and depth doses for any shaped field from the data for circular fields is presented. The depth dose evaluation is based on a measured dose function which is defined as the dose rate at a particular depth for a particular circular field. The evaluated values for the surface and depth dose were compared with experimentally obtained values for three non-circular fields. The good agreement in these data indicates the practicability of the method suggested. (author)

  4. Biokinetics and radiation dosimetry of {sup 14}C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine 'breath tests' using accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gunnarsson, Mikael

    2002-08-01

    {sup 14}C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used {sup 14}C-breath tests: {sup 14}C-triolein (examination of fat malabsorption), urea (detection of Helicobacter pylori infection in the stomach), glycocholic acid and xylose (examination of bacterial overgrowth in the small intestine) by using the highly sensitive accelerator mass-spectrometry (AMS) technique. The AMS technique has been used to measure low {sup 14}C concentrations in small samples of exhaled air, urine, faeces and tissue samples and has improved the base for the estimation of the absorbed dose to various organs and tissues and the effective dose to man. The high sensitivity of the AMS system has also made it possible to perform {sup 14}C breath tests on patient groups which were earlier subject for restriction (e.g. small children). In summary, our results show that for adult patients - and in the case of {sup 14}C-urea breath test also for children down to 3 years of age - the dose contributions are comparatively low, both described as organ doses and as effective doses. For adults, the latter is: {sup 14}C-glycocholic acid - 0.4 mSv/MBq, {sup 14}C-triolein - 0.3 mSv/MBq, {sup 14}C-xylose - 0.1 mSv/MBq and {sup 14}C-urea - 0.04 mSv/MBq. Thus, from a radiation protection point of view there is no reason for restrictions in using any of the {sup 14}C-labelled radiopharmaceutical included in this work in the activities normally used (0.07-0.2 MBq for a 70 kg patient)

  5. Small field electron beam dosimetry using MOSFET detector.

    Science.gov (United States)

    Amin, Md Nurul; Heaton, Robert; Norrlinger, Bern; Islam, Mohammad K

    2010-10-04

    The dosimetry of very small electron fields can be challenging due to relative shifts in percent depth-dose curves, including the location of dmax, and lack of lateral electronic equilibrium in an ion chamber when placed in the beam. Conventionally a small parallel plate chamber or film is utilized to perform small field electron beam dosimetry. Since modern radiotherapy departments are becoming filmless in favor of electronic imaging, an alternate and readily available clinical dosimeter needs to be explored. We have studied the performance of MOSFET as a relative dosimeter in small field electron beams. The reproducibility, linearity and sensitivity of a high-sensitivity microMOSFET were investigated for clinical electron beams. In addition, the percent depth doses, output factors and profiles have been measured in a water tank with MOSFET and compared with those measured by an ion chamber for a range of field sizes from 1 cm diameter to 10 cm × 10 cm for 6, 12, 16 and 20 MeV beams. Similar comparative measurements were also per-formed with MOSFET and films in solid water phantom. The MOSFET sensitivity was found to be practically constant over the range of field sizes investigated. The dose response was found to be linear and reproducible (within ± 1% for 100 cGy). An excellent agreement was observed among the central axis depth dose curves measured using MOSFET, film and ion chamber. The output factors measured with MOSFET for small fields agreed to within 3% with those measured by film dosimetry. Overall results indicate that MOSFET can be utilized to perform dosimetry for small field electron beam.

  6. Dosimetry

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The purpose of ionizing radiation dosimetry is the measurement of the physical and biological consequences of exposure to radiation. As these consequences are proportional to the local absorption of energy, the dosimetry of ionizing radiation is based on the measurement of this quantity. Owing to the size of the effects of ionizing radiation on materials in all of these area, dosimetry plays an essential role in the prevention and the control of radiation exposure. Its use is of great importance in two areas in particular where the employment of ionizing radiation relates to human health: radiation protection, and medical applications. Dosimetry is different for various reasons: owing to the diversity of the physical characteristics produced by different kinds of radiation according to their nature (X- and γ-photons, electrons, neutrons,...), their energy (from several keV to several MeV), the orders of magnitude of the doses being estimated (a factor of about 10 5 between diagnostic and therapeutic applications); and the temporal and spatial variation of the biological parameters entering into the calculations. On the practical level, dosimetry poses two distinct yet closely related problems: the determination of the absorbed dose received by a subject exposed to radiation from a source external to his body (external dosimetry); and the determination of the absorbed dose received by a subject owing to the presence within his body of some radioactive substance (internal dosimetry)

  7. Dosimetry, instrumentation and exposure chambers for dc magnetic field studies

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1979-03-01

    The principal objective of this report is to describe in detail an exposure chamber that was developed at the Lawrence Berkeley Laboratory for automated, noninvasive studies of rodent physiology during exposure to high DC magnetic fields. A second objective is to discuss some of the unique instrumentation problems that must be overcome in order to record bioelectric signals from laboratory animals in the presence of a magnetic field. Finally, a description will be given of the various dosimetry techniques that can be employed for quantitation of magnetic field strength

  8. Dosimetry

    International Nuclear Information System (INIS)

    Rezende, D.A.O. de

    1976-01-01

    The fundamental units of dosimetry are defined, such as exposure rate, absorbed dose and equivalent dose. A table is given of relative biological effectiveness values for the different types of radiation. The relation between the roentgen and rad units is calculated and the concepts of physical half-life, biological half-life and effective half-life are discussed. Referring to internal dosimetry, a mathematical treatment is given to β particle-and γ radiation dosimetry. The absorbed dose is calculated and a practical example is given of the calculation of the exposure and of the dose rate for a gama source [pt

  9. EPR dosimetry in a mixed neutron and gamma radiation field.

    Science.gov (United States)

    Trompier, F; Fattibene, P; Tikunov, D; Bartolotta, A; Carosi, A; Doca, M C

    2004-01-01

    Suitability of Electron Paramagnetic Resonance (EPR) spectroscopy for criticality dosimetry was evaluated for tooth enamel, mannose and alanine pellets during the 'international intercomparison of criticality dosimetry techniques' at the SILENE reactor held in Valduc in June 2002, France. These three materials were irradiated in neutron and gamma-ray fields of various relative intensities and spectral distributions in order to evaluate their neutron sensitivity. The neutron response was found to be around 10% for tooth enamel, 45% for mannose and between 40 and 90% for alanine pellets according their type. According to the IAEA recommendations on the early estimate of criticality accident absorbed dose, analyzed results show the EPR potentiality and complementarity with regular criticality techniques.

  10. Biokinetics and dosimetry in patients administered with 111In-DOTA-Tyr3-octreotide: implications for internal radiotherapy with 90Y-DOTATOC

    International Nuclear Information System (INIS)

    Cremonesi, M.; Ferrari, M.; Maecke, H.R.; Tosi, G.; Zoboli, S.; Chinol, M.; Fiorenza, M.; Paganelli, G.; Stabin, M.G.; Orsi, F.O.; Jermann, E.; Robertson, C.

    1999-01-01

    Recent advances in receptor-mediated tumour imaging have resulted in the development of a new somatostatin analogue, DOTA-dPhe 1 -Tyr 3 -octreotide. This new compound, named DOTATOC, has shown high affinity for somatostatin receptors, ease of labelling and stability with yttrium-90 and favourable biodistribution in animal models. The aim of this work was to evaluate the biodistribution and dosimetry of DOTATOC radiolabelled with indium-111, in anticipation of therapy trials with 90 Y-DOTATOC in patients. Eighteen patients were injected with DOTATOC (10 μg), labelled with 150-185 MBq of 111 In. Blood and urine samples were collected throughout the duration of the study (0-2 days). Planar and single-photon emission tomography images were acquired at 0.5, 3-4, 24 and 48 h and time-activity curves were obtained for organs and tumours. A compartmental model was used to determine the kinetic parameters for each organ. Dose calculations were performed according to the MIRD formalism. Specific activities of >37 GBq/ μmol were routinely achieved. Patients showed no acute or delayed adverse reactions. The residence time for 111 In-DOTATOC in blood was 0.9±0.4 h. The injected activity excreted in the urine in the first 24 h was 73%±11%. The agent localized primarily in spleen, kidneys and liver. The residence times in source organs were: 2.2±1.8 h in spleen, 1.7±1.2 h in kidneys, 2.4±1.9 h in liver, 1.5±0.3 h in urinary bladder and 9.4±5.5 h in the remainder of the body; the mean residence time in tumour was 0.47 h (range: 0.03-6.50 h). Based on our findings, the predicted absorbed doses for 90 Y-DOTATOC would be 7.6±6.3 (spleen), 3.3±2.2 (kidneys), 0.7±0.6 (liver), 2.2±0.3 (bladder), 0.03±0.01 (red marrow) and 10.1 (range: 1.4-31.0) (tumour) mGy/MBq. These results indicate that high activities of 90 Y-DOTATOC can be administered with low risk of myelotoxicity, although with potentially high radiation doses to the spleen and kidneys. Tumour doses were high

  11. Biokinetics and dosimetry in patients administered with {sup 111}In-DOTA-Tyr{sup 3}-octreotide: implications for internal radiotherapy with {sup 90}Y-DOTATOC

    Energy Technology Data Exchange (ETDEWEB)

    Cremonesi, M.; Ferrari, M.; Maecke, H.R.; Tosi, G. [Department of Health Physics, European Institute of Oncology, Milan (Italy); Zoboli, S.; Chinol, M.; Fiorenza, M.; Paganelli, G. [Division of Nuclear Medicine, European Institute of Oncology, via Ripamonti, 435, I-20141-Milan (Italy); Stabin, M.G. [Nuclear Energy Department, Recife, Pernambuco (Brazil); Orsi, F.O. [Department of Radiology, European Institute of Oncology, Milan (Italy); Jermann, E. [Nuclear Medicine Department, University of Basel (Switzerland); Robertson, C. [Department of Epidemiology and Biostatistics, European Institute of Oncology, Milan (Italy)

    1999-08-01

    Recent advances in receptor-mediated tumour imaging have resulted in the development of a new somatostatin analogue, DOTA-dPhe{sup 1}-Tyr{sup 3}-octreotide. This new compound, named DOTATOC, has shown high affinity for somatostatin receptors, ease of labelling and stability with yttrium-90 and favourable biodistribution in animal models. The aim of this work was to evaluate the biodistribution and dosimetry of DOTATOC radiolabelled with indium-111, in anticipation of therapy trials with {sup 90}Y-DOTATOC in patients. Eighteen patients were injected with DOTATOC (10 {mu}g), labelled with 150-185 MBq of {sup 111}In. Blood and urine samples were collected throughout the duration of the study (0-2 days). Planar and single-photon emission tomography images were acquired at 0.5, 3-4, 24 and 48 h and time-activity curves were obtained for organs and tumours. A compartmental model was used to determine the kinetic parameters for each organ. Dose calculations were performed according to the MIRD formalism. Specific activities of >37 GBq/ {mu}mol were routinely achieved. Patients showed no acute or delayed adverse reactions. The residence time for {sup 111}In-DOTATOC in blood was 0.9{+-}0.4 h. The injected activity excreted in the urine in the first 24 h was 73%{+-}11%. The agent localized primarily in spleen, kidneys and liver. The residence times in source organs were: 2.2{+-}1.8 h in spleen, 1.7{+-}1.2 h in kidneys, 2.4{+-}1.9 h in liver, 1.5{+-}0.3 h in urinary bladder and 9.4{+-}5.5 h in the remainder of the body; the mean residence time in tumour was 0.47 h (range: 0.03-6.50 h). Based on our findings, the predicted absorbed doses for {sup 90}Y-DOTATOC would be 7.6{+-}6.3 (spleen), 3.3{+-}2.2 (kidneys), 0.7{+-}0.6 (liver), 2.2{+-}0.3 (bladder), 0.03{+-}0.01 (red marrow) and 10.1 (range: 1.4-31.0) (tumour) mGy/MBq. These results indicate that high activities of {sup 90}Y-DOTATOC can be administered with low risk of myelotoxicity, although with potentially high radiation

  12. Biokinetics and dosimetry in patients administered with [sup 111]In-DOTA-Tyr[sup 3]-octreotide: implications for internal radiotherapy with [sup 90]Y-DOTATOC

    Energy Technology Data Exchange (ETDEWEB)

    Cremonesi, M.; Ferrari, M.; Maecke, H.R.; Tosi, G. (Department of Health Physics, European Institute of Oncology, Milan (Italy)); Zoboli, S.; Chinol, M.; Fiorenza, M.; Paganelli, G. (Division of Nuclear Medicine, European Institute of Oncology, via Ripamonti, 435, I-20141-Milan (Italy)); Stabin, M.G. (Nuclear Energy Department, Recife, Pernambuco (Brazil)); Orsi, F.O. (Department of Radiology, European Institute of Oncology, Milan (Italy)); Jermann, E. (Nuclear Medicine Department, University of Basel (Switzerland)); Robertson, C. (Department of Epidemiology and Biostatistics, European Institute of Oncology, Milan (Italy))

    1999-08-01

    Recent advances in receptor-mediated tumour imaging have resulted in the development of a new somatostatin analogue, DOTA-dPhe[sup 1]-Tyr[sup 3]-octreotide. This new compound, named DOTATOC, has shown high affinity for somatostatin receptors, ease of labelling and stability with yttrium-90 and favourable biodistribution in animal models. The aim of this work was to evaluate the biodistribution and dosimetry of DOTATOC radiolabelled with indium-111, in anticipation of therapy trials with [sup 90]Y-DOTATOC in patients. Eighteen patients were injected with DOTATOC (10 [mu]g), labelled with 150-185 MBq of [sup 111]In. Blood and urine samples were collected throughout the duration of the study (0-2 days). Planar and single-photon emission tomography images were acquired at 0.5, 3-4, 24 and 48 h and time-activity curves were obtained for organs and tumours. A compartmental model was used to determine the kinetic parameters for each organ. Dose calculations were performed according to the MIRD formalism. Specific activities of >37 GBq/ [mu]mol were routinely achieved. Patients showed no acute or delayed adverse reactions. The residence time for [sup 111]In-DOTATOC in blood was 0.9[+-]0.4 h. The injected activity excreted in the urine in the first 24 h was 73%[+-]11%. The agent localized primarily in spleen, kidneys and liver. The residence times in source organs were: 2.2[+-]1.8 h in spleen, 1.7[+-]1.2 h in kidneys, 2.4[+-]1.9 h in liver, 1.5[+-]0.3 h in urinary bladder and 9.4[+-]5.5 h in the remainder of the body; the mean residence time in tumour was 0.47 h (range: 0.03-6.50 h). Based on our findings, the predicted absorbed doses for [sup 90]Y-DOTATOC would be 7.6[+-]6.3 (spleen), 3.3[+-]2.2 (kidneys), 0.7[+-]0.6 (liver), 2.2[+-]0.3 (bladder), 0.03[+-]0.01 (red marrow) and 10.1 (range: 1.4-31.0) (tumour) mGy/MBq. These results indicate that high activities of [sup 90]Y-DOTATOC can be administered with low risk of myelotoxicity, although with potentially high radiation

  13. Dosimetry in clinical static magnetic fields using plastic scintillation detectors

    DEFF Research Database (Denmark)

    Stefanowicz, S.; Latzel, H.; Lindvold, Lars René

    2013-01-01

    . In conclusion, we found some deviations up to 7% of the supposed signal. Although the scintillators are of much denser material, we measured the same behavior in signal as in (Meijsing et al., 2009) for a Farmer ionization chamber or as in (Raaijmakers et al., 2007) for films described which indicates radiation......-vivo dosimetry in radiation treatments and diagnostics and could be, being all-optical, promising candidates for this application. To study the basic feasibility of using PSDs with organic scintillators in magnetic fields, we measured the response of these dosimeters in presence of magnetic fields up to 1 T...

  14. Chernobyl Experience in the Field of Retrospective Dosimetry

    International Nuclear Information System (INIS)

    Chumak, V.; Bakhanova, E.

    2011-01-01

    Chernobyl accident, which occurred on April 26, 1986 at NPP located less than 150 km north of Kiev, is the largest nuclear accident ever. Unprecedented scale of the accident was determined not only by the amount of released activity, but also by a number of population and workers involved and, therefore, exposed to enhanced doses of ionizing radiation. Population of the 30-km exclusion zone numbering about 116,000 persons of all ages and both genders was evacuated within days and weeks after the accident, emergency workers called ''liquidators of the accident'' (males age 20-50) were involved into clean-up and recovery for 5 years and their number is estimated as 600,000, about 300,000 are Ukrainian citizens. Due to unexpected and excessively large scale accident, none of residents had personal dosimeters, personal dosimetry of liquidators was not total, dosimetry techniques and practices were far from the optimum. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. This need was responded by implementation of wide scale dose reconstruction efforts, which covered main exposed cohorts and encompassed broad variety of newly developed methods: analytical (time-and-motion), modeling, biological and physical (EPR spectroscopy of teeth, TL of quartz). The presentation summarizes vast experience accumulated by RCRM in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up medical consequences of Chernobyl accident and study health effects of ionizing radiation, in particular, Ukrainian-American studies of cataracts and leukemia among liquidators. Over 25 years passed after Chernobyl accident a broad variety of retrospective dosimetry problems was addressed by the team of Research Center for Radiation Medicine AMS Ukraine. In

  15. Field arrangement and dosimetry verification for concave target

    International Nuclear Information System (INIS)

    Chen Liang; Wang Huankun; Li Yumin

    2005-01-01

    Objective: To provide a method of radiotherapy field arrangement for concave paraspinal target. Methods: Plan was designed for concave target in wax phantom and the selected patients by the guidance of beam eye view (BEV) provided by a 3D treatment planning system (CREAT EXPERT). In BEV, the inner border of all tangential fields was 2 mm out of the organ at risk (OAR) and the outer border was 5 mm beyond the target. Dosimetry films and ion chamber were used to verify the dose distribution and point dose in the wax phantom. Results: Dose distribution in phantom and patient was homogeneous. The mean dose of OAR in phantom did not exceed 16% of the prescribed dose. Isodose curves dropped more than 8% per mm between the target and OAR in the phantom. Film dosimetry coincided well with the calculated results. Position error in high dose region was with- in 4 mm and absolute dose errors were no more than 5%. Conclusion: Tangential field arrangement is valuable and practical in radiotherapy for concave paraspinal targets. (authors)

  16. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Dose reconstruction. Final report

    International Nuclear Information System (INIS)

    Jacob, P.; Aragno, D.; Bailiff, I.K.

    2000-01-01

    The project Dose Reconstruction was conducted within the five work packages: - EPR with teeth, - Chromosome painting (FISH) in lymphocytes, - Luminescence methods, - Modelling, and - Evaluation. (orig.)

  17. Correction factors for clinical dosemeters used in large field dosimetry

    International Nuclear Information System (INIS)

    Campos, L.L.; Caldas, L.

    1989-08-01

    The determination of the absorbed dose in high-energy photon and electron beams by the user is carried out as a two-step procedure. First the ionization chamber is calibrated at a reference quality by the user at a standard laboratory, and then the chamber is used to determine the absorbed dose with the user's beam. A number of conversion and correction factors have to be applied. Different sets of factors are needed depending on the physical quantity the calibration refers to, the calibration geometry and the chamber design. Another correction factor to be introduced for the absorbed dose determination in large fields refers to radiation effects on the stem, cable and sometimes connectors. A simple method was developed to be suggested to hospital physicists to be followed during large radiation field dosimetry, in order to evaluate the radiation effects of cables and connectors and to determine correction factors for each system or geometry. (author) [pt

  18. Dimer of the peptide cycle (Ar-Gly-Asp-D-Phe-Lys) radiolabeled with 99mTc for the integrin s over-expression image: formulation, biokinetics and dosimetry

    International Nuclear Information System (INIS)

    Ortiz A, Z.

    2013-01-01

    In breast cancer, α(v)β(3) and/or α(v)β(5) integrin s are over-expressed in both endothelial and tumour cells. Radiolabeled peptides based on the RGD (Arg-Gly-Asp) sequence are radiopharmaceuticals with high affinity and selectivity for those integrin s. The RGD-dimer peptide (E-[c(RGDfK)] 2 ) radiolabeled with 99m Tc has been reported as a radiopharmaceutical with 10-fold higher affinity for the α(v)β(3) integrin as compared to the RGD-monomer. EDDA (Ethylenediamine-N,N-diacetic acid) is a hydrophilic molecule that may favours renal excretion when used as coligand in the 99m Tc labelling of HYNIC-peptides and can easily be formulated in a lyophilized kit. Aim: Establish a biokinetic model for 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 prepared from lyophilized kits and evaluate the dosimetry as breast cancer imaging agent. Methods: 99m Tc labelling was performed by addition of sodium pertechnetate solution and 0.2 M phosphate buffer ph 7.0 to a lyophilized formulation containing E-[c(RGDfK)] 2 , EDDA, tricine, mannitol and stannous chloride. Radiochemical purity was evaluated by reversed phase HPLC and ITLC-SG analyses. Stability studies in human serum were carried out by size-exclusion HPLC. In-vitro cell uptake was tested using breast cancer cells (MCF7, T47D and MDA-MB-231) with blocked and non-blocked receptors. Biodistribution and tumour uptake were determined in MCF7 tumour-bearing nude mice with blocked and non-blocked receptors, and images were obtained using a micro-SPECT/CT. Whole-body images from seven healthy women were acquired at 1, 3, 6 and 24 h after 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 administration obtained with radiochemical purities of >94 %. Regions of interest (ROIs) were drawn around source organs on each time frame. Each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 time-activity curves in each organ in order to adjust the biokinetic model and to

  19. Biokinetics and dosimetry in patients of {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesin: images of GRP receptors; Biocinetica y dosimetria en humanos de {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesina: imagenes de receptores GRP

    Energy Technology Data Exchange (ETDEWEB)

    Santos C, C L [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2007-07-01

    The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [{sup 99m}Tc]EDDA/HYNIC-Lys{sup 3}-bombesin ({sup 99m}Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red

  20. Uranium: biokinetics and toxicity

    International Nuclear Information System (INIS)

    Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A.

    2000-01-01

    This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation

  1. Dosimetry of small electron fields shaped by lead

    International Nuclear Information System (INIS)

    Perez, M.; Hill, R.; Whitaker, M.; Greig, L.; West, M.; Jones, L.

    2000-01-01

    Full text: Electron fields can be used to treat superficial cancers. Field shaping can be achieved by placing lead on the patient surface to minimise the dose to surrounding areas and may improve beam penumbra compared to using standard applicators. However, significant dosimetry changes under high density material edges for electron fields have been reported (W Pohlit and KH Manegold, cited in The Physics of Radiation Therapy, P.M. Khan, 1994). This project evaluated the dosimetry of small dimension electron fields shaped with lead placed on the surface. Comparisons were made between circular lead cutouts (3 and 5cm diameters) and an open electron applicator (5cm diameter). For each of these fields depth doses and profiles were measured using a diode detector in a water phantom, and isodoses were measured using X-Omat film sandwiched within a Solid water phantom. Output factors were measured in the Solid water using a Markus parallel plate ionisation chamber. The effect of the lead thickness on the profiles and output was quantified and the thickness used for the final measurements selected so as to give less than 5% transmission of the primary dose. Penumbral widths for 6MeV and 8MeV using the lead cutouts showed distinct differences compared with the open applicator. At depths of the 90% relative dose the profiles for lead shaped fields showed tighter penumbra widths by an average of 2 mm. This became more pronounced nearer the surface where, at 2mm depth, the difference in penumbral widths was an average of 4mm. The 3cm lead cutouts showed surface dose increases of 6% and 9% for 6MeV and 8 MeV respectively. Depth dose parameters (D max and R 90 ) varied by no more than 2mm between the lead cutouts and the open applicator measurements. Lead can be used to shape electron fields for radiotherapy treatments. Depth dose characteristics do not vary significantly with a 5 cm circular applicator. The penumbral width indicates less isodose spread for the lead cutout

  2. Reference dosimetry and small-field dosimetry in external beam radiotherapy: Results from a Danish intercomparison study

    DEFF Research Database (Denmark)

    Beierholm, Anders Ravnsborg; Behrens, Claus F.; Sibolt, Patrik

    methods was performed by DTU Nutech at six Danish clinics. The first part of the intercompa-rison regarded the consistency of reference dosimetry. Absorbed dose to water under reference conditions was measured using a Farmer ionization chamber, and was found to agree within 1 % with the daily dose checks......-specific correction factors for non-reference fields....

  3. Biological dosimetry for mixed gamma-neutron field

    International Nuclear Information System (INIS)

    Brandao, J.O.C.; Santos, J.A.L.; Souza, P.L.G.; Lima, F.F.; Vilela, E.C.; Calixto, M.S.; Santos, N.

    2011-01-01

    There is increasing concern about airline crew members (about one million worldwide) exposed to measurable neutrons doses. Historically, cytogenetic biodosimetry assays have been based on quantifying asymmetrical chromosome alterations (dicentrics, centric rings and acentric fragments) in mitogen-stimulated T-lymphocytes in their first mitosis after radiation exposure. Increased levels of chromosome damage in peripheral blood lymphocytes are a sensitive indicator of radiation exposure and they are routinely exploited for assessing radiation absorbed dose after accidental or occupational exposure. Since radiological accidents are not common, not all nations feel that it is economically justified to maintain biodosimetry competence. However, dependable access to biological dosimetry capabilities is completely critical in event of an accident. In this paper the dose-response curve was measured for the induction of chromosomal alterations in peripheral blood lymphocytes after chronic exposure in vitro to mixed gamma-neutron field. Blood was obtained from one healthy donor and exposed to two mixed gamma-neutron field from sources 241 AmBe (20 Ci) at the Neutron Calibration Laboratory (NCL - CRCN/NE - PE - Brazil). The evaluated absorbed doses were 0.2 Gy; 1.0 Gy and 2.5 Gy. The dicentric chromosomes were observed at metaphase, following colcemide accumulation and 1000 well-spread metaphases were analyzed for the presence of dicentrics by two experts after painted by giemsa 5%. The preliminary results showed a linear dependence between radiations absorbed dose and dicentric chromosomes frequencies. Dose-response curve described in this paper will contribute to the construction of calibration curve that will be used in our laboratory for biological dosimetry. (author)

  4. Stereotactic radiosurgery photon field profile dosimetry using conventional dosimeters and polymer gel dosimetry. Analysis and inter-comparison

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, E; Maris, T G; Zacharopoulou, F; Papadakis, A [Department of Medical Physics, Faculty of Medicine, University of Crete, 711 10 Stavrakia-Heraklion, Crete (Greece); Manolopoulos, S; Green, S [Queen Elizabeth Medical Centre, University Hospital Birmingham NHS Trust, Birmingham B15 2TH (United Kingdom); Wojnecki, C, E-mail: epappas@edu.med.uoc.gr

    2009-05-01

    Small photon fields are increasingly used in modern radiotherapy and especially in IMRT and SRS/SRT treatments. Accurate beam profile measurements of such beams are crucial for a precise and effective treatment. In this work four different dosimetric methods have been used for profile measurements of three small 6 MV circular fields having diameters of 7.5, 15.0 and 30.0 mm. A small sensitive volume air ion chamber, a diamond detector, a novel silicon-diode array and Vinyl-Pyrrolidone based polymer gel dosimetry. The results of this work reveal the well-known disadvantages and/or problems of the conventional dosimeters for this kind of measurements and support that polymer gel dosimetry may overcome these problems. Conclusively, it is estimated that polymer gels could play an important role towards the minimization of the total SRS/SRT treatment error that is related with small field profile measurements.

  5. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-15

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, gamma) process in Na sup 2 sup 3 , giving rise to Na sup 2 sup 4 , which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na sup 2 sup 4 , is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na sup 2 sup 3 in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na sup 2 sup 4 /Na sup 2 sup 3 in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R sub B reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzmann transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given

  6. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-01

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, {gamma}) process in Na{sup 23}, giving rise to Na{sup 24}, which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na{sup 24}, is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na{sup 23} in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na{sup 24}/Na{sup 23} in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R{sub B} reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzman transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given. A summary of the 4{pi

  7. Small Field Dosimetry Comparing Measured Data Versus the ADAC Pinnacle 3 Model

    National Research Council Canada - National Science Library

    Ludolph, Daniel

    2004-01-01

    .... While this method can optimize conformity to tumors and provide better sparing of surrounding tissue, it also presents a host of challenges due to reliance on dosimetry data for small field sizes...

  8. EVIDOS: Individual dosimetry in mixed neutron and photon radiation fields

    International Nuclear Information System (INIS)

    Vanhavere, F.

    2006-01-01

    The EVIDOS project (partly funded by the European Commission RTD Programme: Nuclear Energy, Euratom Framework Programme V, 1998-2002, Contract No FIKR-CT-2001-00175) aimed at improving individual monitoring in mixed neutron-photon radiation fields by evaluating the performance of routine and novel personal dosimeters for mixed radiation, and by giving guidelines for deriving sufficiently accurate values of personal dose equivalent from the readings of area survey instruments and dosimeters. The main objective of EVIDOS was to evaluate different methods for individual dosimetry in mixed neutron-photon work-places in nuclear industry. This implied a determination of the capabilities and limitations of personal dosimeters and the establishment of methods to enable sufficiently accurate values of personal dose equivalent from spectrometers, area survey instruments and routine personal dosimeters. Also novel electronic personal dosimeters were investigated. To this end spectrometric and dosimetric investigations in selected representative workplaces in nuclear industry where workers can receive significant neutron doses were performed. As part of this project, a number of tasks were executed, in particular: (1) the determination of the energy and direction distribution of the neutron fluence; (2) the derivation of the (conventionally true) values of radiation protection quantities; (3) the determination of the readings of routine and innovative personal dosimeters and of area monitors; and (4) the comparison between dosimeter readings and values of the radiation protection quantities

  9. The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects.

    Science.gov (United States)

    Fell, T P

    2007-01-01

    The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts--the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES.

  10. The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects

    International Nuclear Information System (INIS)

    Fell, T.P.

    2007-01-01

    The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts - the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. (author)

  11. Development of a definitive internal dosimetry code

    International Nuclear Information System (INIS)

    Miller, G.; Inkret, W.C.; Schillaci, M.E.

    1996-01-01

    Internal dosimetry may be divided into tow main problems: (1) the forward (scientific) problem of determining biokinetics models that describe how radionuclides are taken into the body, distributed in body tissues, and excreted, and (2) the inverse (mathematical) problem: given the measured amounts in excreta and assuming a biokinetic model, to determine the times and amounts of intakes into the body. The inverse problem of internal dosimetry is, in fact, a generic problem studied in other fields (e.g., image reconstruction, spectral deconvulution, and model parameter fitting). We have developed a code for plutonium internal dosimetry using the maximum entropy method, a method for solving underdetermined inverse problems with a positivity constraint. Within the framework of Bayesian statistics, we believe the definitive approach is to examine the Bayesian posterior probability describing the probability of an intake scenario (X i ) read ( ... ) as open-quotes the set of,close quotes where X i denotes the intake amount that occurs on the with day. For plutonium, for a worker with a long employment history, this is a very high dimensional probability space, since there may be on the order of 10,000 days when intakes may have occurred. Within this high dimensional space, we calculate the mean intake scenario as i > where denotes the expectation value over the posterior probability distribution. Similarly, we calculate uncertainties and other relevant quantities, such as X 2 , as expectation values over the posterior distribution. Thanks to a recent breakthrough in describing the mathematical structure of the intake process (a Poisson sum representation of intakes), we have developed the initial version of a Bayesian expectation-value algorithm for internal dosimetry reconstructions

  12. Spectral distribution of particle fluence in small field detectors and its implication on small field dosimetry.

    Science.gov (United States)

    Benmakhlouf, Hamza; Andreo, Pedro

    2017-02-01

    Correction factors for the relative dosimetry of narrow megavoltage photon beams have recently been determined in several publications. These corrections are required because of the several small-field effects generally thought to be caused by the lack of lateral charged particle equilibrium (LCPE) in narrow beams. Correction factors for relative dosimetry are ultimately necessary to account for the fluence perturbation caused by the detector. For most small field detectors the perturbation depends on field size, resulting in large correction factors when the field size is decreased. In this work, electron and photon fluence differential in energy will be calculated within the radiation sensitive volume of a number of small field detectors for 6 MV linear accelerator beams. The calculated electron spectra will be used to determine electron fluence perturbation as a function of field size and its implication on small field dosimetry analyzed. Fluence spectra were calculated with the user code PenEasy, based on the PENELOPE Monte Carlo system. The detectors simulated were one liquid ionization chamber, two air ionization chambers, one diamond detector, and six silicon diodes, all manufactured either by PTW or IBA. The spectra were calculated for broad (10 cm × 10 cm) and narrow (0.5 cm × 0.5 cm) photon beams in order to investigate the field size influence on the fluence spectra and its resulting perturbation. The photon fluence spectra were used to analyze the impact of absorption and generation of photons. These will have a direct influence on the electrons generated in the detector radiation sensitive volume. The electron fluence spectra were used to quantify the perturbation effects and their relation to output correction factors. The photon fluence spectra obtained for all detectors were similar to the spectrum in water except for the shielded silicon diodes. The photon fluence in the latter group was strongly influenced, mostly in the low-energy region, by

  13. Dosimetry considerations in the head and retina for extremely low frequency electric fields

    International Nuclear Information System (INIS)

    Taki, M.; Suzuki, Y.; Wake, K.

    2003-01-01

    Magnetophosphenes are investigated from the viewpoint of electromagnetic dosimetry. Induced current density and internal electric fields at the threshold of perception are estimated by analytical and numerical calculations, assuming different models. Dosimetry for electrophoshenes is also discussed and compared with that for magnetophosphenes. The distribution of current density and internal electric fields is consistent with the experimental observation that flashing sensations reach their greatest intensity at the periphery of the visual field, for both electro and magnetophosphenes. The estimated thresholds in internal electric fields are consistent for magnetophosphenes and for electrophosphenes, respectively. The magnitudes of the thresholds, however, differ by about 10-fold. The thresholds in induced current density are critically dependent on the conductivity of the eye assumed for the calculations. The effect of thin membrane structure is also discussed with regard to the difference between electric field and magnetic field exposures. (author)

  14. The internal dosimetry code PLEIADES.

    Science.gov (United States)

    Fell, T P; Phipps, A W; Smith, T J

    2007-01-01

    The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts-the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included.

  15. The internal dosimetry code PLEIADES

    International Nuclear Information System (INIS)

    Fell, T. P.; Phipps, A. W.; Smith, T. J.

    2007-01-01

    The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts - the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included. (authors)

  16. Correction factors for clinical dosemeters used in dosimetry of large fields

    International Nuclear Information System (INIS)

    Campos, L.L.; Caldas, L.V.E.

    1989-01-01

    A method for using by physicist for evaluation of irradiation effect in cables connectors of ionization chambers, and the consequent determination of adequate conection factors, for each measure the geometric system, during the realization of large fields radiation dosimetry are studied. (C.G.C.) [pt

  17. Dosimetry of the Embalse nuclear power plant neutron/gamma mixed fields

    International Nuclear Information System (INIS)

    Salas, C.A.

    1990-01-01

    The aim of this work is to describe the method used at the Embalse nuclear power plant for carrying out personal dosimetry of the agents affected to the tasks on the Embalse nuclear power plant neutron-gamma mixed fields. (Author) [es

  18. High dose per fraction dosimetry of small fields with Gafchromic EBT2 film

    International Nuclear Information System (INIS)

    Hardcastle, Nicholas; Basavatia, Amar; Bayliss, Adam; Tome, Wolfgang A.

    2011-01-01

    Purpose: Small field dosimetry is prone to uncertainties due to the lack of electronic equilibrium and the use of the correct detector size relative to the field size measured. It also exhibits higher sensitivity to setup errors as well as large variation in output with field size and shape. Radiochromic film is an attractive method for reference dosimetry in small fields due to its ability to provide 2D dose measurements while having minimal impact on the dose distribution. Gafchromic EBT2 has a dose range of up to 40 Gy; therefore, it could potentially be useful for high dose reference dosimetry with high spatial resolution. This is a requirement in stereotactic radiosurgery deliveries, which deliver high doses per fraction to small targets. Methods: Targets of 4 mm and 12 mm diameters were treated to a minimum peripheral dose of 21 Gy prescribed to 80% of the maximum dose in one fraction. Target doses were measured with EBT2 film (both targets) and an ion chamber (12 mm target only). Measured doses were compared with planned dose distributions using profiles through the target and minimum peripheral dose coverage. Results: The measured target doses and isodose coverage agreed with the planned dose within ±1 standard deviation of three measurements, which were 2.13% and 2.5% for the 4 mm and 12 mm targets, respectively. Conclusions: EBT2 film is a feasible dosimeter for high dose per fraction reference 2D dosimetry.

  19. Dosimetry of cone-defined stereotactic radiosurgery fields with a commercial synthetic diamond detector.

    Science.gov (United States)

    Morales, Johnny E; Crowe, Scott B; Hill, Robin; Freeman, Nigel; Trapp, J V

    2014-11-01

    Small field x-ray beam dosimetry is difficult due to lack of lateral electronic equilibrium, source occlusion, high dose gradients, and detector volume averaging. Currently, there is no single definitive detector recommended for small field dosimetry. The objective of this work was to evaluate the performance of a new commercial synthetic diamond detector, namely, the PTW 60019 microDiamond, for the dosimetry of small x-ray fields as used in stereotactic radiosurgery (SRS). Small field sizes were defined by BrainLAB circular cones (4-30 mm diameter) on a Novalis Trilogy linear accelerator and using the 6 MV SRS x-ray beam mode for all measurements. Percentage depth doses (PDDs) were measured and compared to an IBA SFD and a PTW 60012 E diode. Cross profiles were measured and compared to an IBA SFD diode. Field factors, ΩQclin,Qmsr (fclin,fmsr) , were calculated by Monte Carlo methods using BEAMnrc and correction factors, kQclin,Qmsr (fclin,fmsr) , were derived for the PTW 60019 microDiamond detector. For the small fields of 4-30 mm diameter, there were dose differences in the PDDs of up to 1.5% when compared to an IBA SFD and PTW 60012 E diode detector. For the cross profile measurements the penumbra values varied, depending upon the orientation of the detector. The field factors, ΩQclin,Qmsr (fclin,fmsr) , were calculated for these field diameters at a depth of 1.4 cm in water and they were within 2.7% of published values for a similar linear accelerator. The corrections factors, kQclin,Qmsr (fclin,fmsr) , were derived for the PTW 60019 microDiamond detector. The authors conclude that the new PTW 60019 microDiamond detector is generally suitable for relative dosimetry in small 6 MV SRS beams for a Novalis Trilogy linear equipped with circular cones.

  20. Advances in electron dosimetry of irregular fields; Avances en dosimetria de electrones de campos irregulares

    Energy Technology Data Exchange (ETDEWEB)

    Mendez V, J. [Departamento de Radioterapia, Instituto de Enfermedades Neoplasicas, Avenida Angamos Este 2520, Lima 34 (Peru)

    1998-12-31

    In this work it is presented an advance in Electron dosimetry of irregular fields for beams emitted by linear accelerators. At present diverse methods exist which are coming to apply in the Radiotherapy centers. In this work it is proposed a method for irregular fields dosimetry. It will be allow to calculate the dose rate absorbed required for evaluating the time for the treatment of cancer patients. Utilizing the results obtained by the dosimetric system, it has been possible to prove the validity of the method describe for 12 MeV energy and for square field 7.5 x 7.5 cm{sup 2} with percentile error less than 1 % . (Author)

  1. Scientific days on electromagnetic fields: from dosimetry to human health - Conference proceedings

    International Nuclear Information System (INIS)

    Wiart, J.; Ghanmi, A.; Picon, O.; Conil, E.; Varsier, N.; Hadjem, A.; Sudret, B.; Magne, I.; Souques, M.; Gaudaire, F.; De Seze, R.; Jawad, O.; Lautru, D.; Dricot, J.M.; Horlin, F.; De Doncker, P.; Drissaoui, A.; Musy, F.; Nicolas, L.; Perrussel, R.; Scorretti, R.; Voyer, D.; Jala, M.; Moulines, E.; Levy-Leduc, C.; Mahfouz, Z.; Gati, A.; Fouad Hanna, V.; Leveque, P.; Arnaud-Cormos, D.; Zhadobov, M.; Jarrige, P.; Gaborit, G.; Kohler, S.; Ticaud, N.; Duvillaret, L.; Guelilia, Z.; Loison, R.; Gillard, R.; Laisne, A.; Favet, D.; Benadhira, R.; Mir, L.; Nadi, M.; Kourtiche, D.; Gazeau, F.; Wilhelm, C.; Delemotte, L.; Breton, M.; Tarek, M.; Marc-Vergnes, J.P.; Yardin, C.; Perrin, A.; Le Drean, Y.; Sauleau, R.; Lambrozo, J.; Selmaoui, B.; Ghosn, R.; Thuroczy, G.; Villegier, A.S.; Loos, N.; Brenet-Dufour, V.; Liabeuf, S.; Bach, V.; Moretti, D.; Lewis, N.; Garenne, A.; Poulletier De Gannes, F.; Haro, E.; Lagroye, I.; Bornat, Y.; Boutaib, Y.; Saighi, S.; Renaud, S.; Veyre, B.; Schuz, J.; Deltour, I.; Van Deventer, E.; Vecchia, P.; Merckel, O.; Bellaouel, A.; Demaret, P.; Donati, P.; Jovanovic, D.; Chauvin, S.; Desreumaux, J.P.; Fouquet, L.; Picard, D.; Massardier-Pilonchery, A.; Hours, M.; Bergeret, A.; Person, C.; Toutain, Y.; Butet, R.; Berrahma, K.; Balderelli, I.; Stelmaszyk, V.; Cretallaz, C.; Lamproglou, I.; Amourette, C.; Diserbo, M.; Fauquette, W.; Martigne, P.; Collin, A.; Lagroye, I.; Ait Aissa, S.; Hurtier, A.; Taxile, M.; Le Montagner, L.; Athane, A.; Duleu, S.; Percherancier, Y.; Geffard, M.; Ruffie, G.; Billaudel, B.; Veyret, B.; Pelletier, A.; Delanaud, S.; Libert, J.P.; Schunck, T.; Bieth, F.; Soubere Mahamoud, Y.; Le Quement, C.; Ferrand, G.; Le Guevel, R.; Carton, P.H.; Luong, M.; Tanvir, S.; Selmaoui, B.; Silva Pires-Antonietti, V.; Sonnet, P.; Pulvin, S.; Kuster, O.; Tetelin, C.

    2012-04-01

    This document brings together the available presentations (articles and slides) given at the URSI scientific days on electromagnetic fields: dosimetry, peoples' exposure, biological and health risks, risk management, and medical uses. 48 presentations are compiled in this document and deal with: 1 - Stochastic dosimetry: variability challenge; 2 - How to estimate the exposure to 50/60 Hz magnetic field in an epidemiological study?; 3 - Joint analysis of population exposure and radio coverage of GSM and UMTS mobile phone networks; 4 - Study of the specific energy absorption rate (SAR) sensitiveness to phone positions near the head for 2 GSM mobile phones; 5 - Statistical Study of SAR under Wireless Channel - Exposure in Indoor Environment; 6 - Uncertainty propagation in numerical dosimetry: how to reduce calculation costs?; 7 - Use of a simplified pregnant woman model for foetus exposure analysis; 8 - SAR estimation using multi-exposure with a mobile phone; 9 - State-of-the-art in experimental dosimetry (RF and pulses); 10 - Mm-waves dosimetry: issues, stakes and actual solutions; 11 - Use of DG-FDTD for a dosimetry calculation in a strongly multi-scale problem: determination of the eye-SAR near a HF/VHF vehicle-borne source; 12 - Dosimetric measurements with a fiber-type electro-optical sensor; 13 - Partial experimental evaluation of basic restrictions in the HF/VHF range; 14 - Repetitive trans-cranial magnetic stimulation Stimulation (rTMS) in psychiatry: present day situation and perspectives; 15 - Medical applications of electric fields; 16 - Measurements for life: new perspectives? 17 - Nano-particles and magnetic stimuli for medical imaging and therapy; 18 - Molecular Insights into electroporation and siRNA electro-transfer through model cell membranes; 19 - State of knowledge on electromagnetic fields hypersensitivity (HS-CEM); 20 - Experimentation methodology: from results to interpretation; 22 - Mm waves - update on biological effects at 40-60 GHz; 23

  2. MO-D-BRD-02: In Memoriam of Bengt Bjarngard: SBRT II: Small Field Dosimetry - TG155

    International Nuclear Information System (INIS)

    Das, I; Reft, C

    2014-01-01

    Specialized radiation treatment such as SRS/SRT. SBRT, IMRT, VMAT, Tomotherapy, CyberKnife and Gamma Knife use small fields or combination of small fields where dosimetry is challenging and uncertain due to non-equilibrium conditions such as longitudinal and lateral disequilibrium. Additionally the primary photon fluence is greatly affected by the obstruction of the source size by the jaws creating a large dose gradient across the field. Electronic equilibrium is a phenomenon associated with the range of secondary particles which depend on the beam energy, photon spectrum and the composition of the medium. Additionally, the finite size of detectors creates volume averaging and fluence perturbations especially in small fields. The IAEA/AAPM has provided a frame work for non-compliant reference dosimetry in small fields1. The AAPM TG-1552 has adopted this frame work to provide guidelines in relative dosimetry. This course provides the insight of TG-155 that defines small field, provides recommendations for suitable detectors and associated correction factors to convert reading to dose. Recommendations of a good working practice for relative dosimetry measurements (PDD, TMR, output factor, etc.) and dose calculations based on the new formulation is are elaborated. It also discusses beam modeling and dose calculations as a critical step in clinical utilization of small field radiotherapy. Small errors in beam data, approximations in dose algorithms, or misaligned of detectors and field settings can propagate into large errors in planned and delivered dose. The modeling and treatment planning aspects of small field dosimetry are reviewed with emphasis on the most critical parts for ensuring accurate and safe radiation therapy. Discussion on k(fmsr, fclin) for commercially available detectors are also provided.1 P. Alfonso, P. Andreo, R. Capote, M. S. Huq, W. Kilby, P. Kjall, T. R. Mackie, H. Palmans, K. Rosser, J. Seuntjens, W. Ullrich and S. Vatnitsky, “A new

  3. Small-Field Dosimetry in A 6 MV Photon Beam Using Alanine and Liquid Ionisation Chamber

    DEFF Research Database (Denmark)

    Zimmermann, S.; Riis, H. L.; Hjelm-Hansen, M.

    2012-01-01

    Purpose/Objective: Dosimetry of small field sizes in MV photon beams is an increasingly important subject, and a generally accepted guideline for clinical measurements is still lacking. The present comparative study was carried out to further investigate the use of alanine and the PTW microLion...... of each field and depth. This dose maximum was measured for each field using a Scanditronix Wellhöfer photon field diode. The same measurements were carried out using a liquid ionchamber, PTW microLion, irradiated by 500 MU. The output of the accelerator was controlled by a PTW semiflex ion chamber...

  4. An optimization strategy for a biokinetic model of inhaled radionuclides

    International Nuclear Information System (INIS)

    Shyr, L.J.; Griffith, W.C.; Boecker, B.B.

    1991-01-01

    Models for material disposition and dosimetry involve predictions of the biokinetics of the material among compartments representing organs and tissues in the body. Because of a lack of human data for most toxicants, many of the basic data are derived by modeling the results obtained from studies using laboratory animals. Such a biomathematical model is usually developed by adjusting the model parameters to make the model predictions match the measured retention and excretion data visually. The fitting process can be very time-consuming for a complicated model, and visual model selections may be subjective and easily biased by the scale or the data used. Due to the development of computerized optimization methods, manual fitting could benefit from an automated process. However, for a complicated model, an automated process without an optimization strategy will not be efficient, and may not produce fruitful results. In this paper, procedures for, and implementation of, an optimization strategy for a complicated mathematical model is demonstrated by optimizing a biokinetic model for 144Ce in fused aluminosilicate particles inhaled by beagle dogs. The optimized results using SimuSolv were compared to manual fitting results obtained previously using the model simulation software GASP. Also, statistical criteria provided by SimuSolv, such as likelihood function values, were used to help or verify visual model selections

  5. A recycling model of the biokinetics of systemic tellurium.

    Science.gov (United States)

    Giussani, Augusto

    2014-11-01

    To develop a compartmental model of the systemic biokinetics of tellurium required for calculating the internal dose and interpreting bioassay measurements after incorporation of radioactive tellurium. The compartmental model for tellurium was developed with the software SAAM II v. 2.0 (©The Epsilon Group, Charlottesville, Virginia, USA). Model parameters were determined on the basis of published retention and excretion data in humans and animals. The model consists of two blood compartments, one compartment each for liver, kidneys, thyroid, four compartments for bone tissues and a generic compartment for the soft tissues. The model predicts a rapid urinary excretion of systemic tellurium: 45% in the first 24 h and 84% after 50 d. Faecal excretion amounts to 0.4% after 3 d and 9% after 50 d. Whole body retention is 55% after one day, and 2.8% after 100 d. These values as well as the retained fractions in the single organs are reasonably consistent with the available human and animal data (studies with swine and guinea pigs). The proposed model gives a realistic description of the available biokinetic data for tellurium and will be adopted by the International Commission on Radiological Protection for applications in internal dosimetry.

  6. Status report on dosimetry benchmark neutron field development, characterization, and application

    International Nuclear Information System (INIS)

    Fabry, A.; Grundl, J.A.; McElroy, W.N.; Lippincott, E.P.; Farrar, H. IV.

    1977-01-01

    The report attempts to present a brief, but comprehensive review of the status and future directions of benchmark neutron field development, characterization and application in perspective with two major objectives of reactor dosimetry: (1) fuel fission rate and burn-up passive monitoring, and (2) correlation of materials irradiation damage effects and projection to commercial power plants. The report focuses on the Light Water Reactor and Fast Breeder Reactor program needs

  7. Performance analysis of numeric solutions applied to biokinetics of radionuclides

    International Nuclear Information System (INIS)

    Mingatos, Danielle dos Santos; Bevilacqua, Joyce da Silva

    2013-01-01

    Biokinetics models for radionuclides applied to dosimetry problems are constantly reviewed by ICRP. The radionuclide trajectory could be represented by compartmental models, assuming constant transfer rates between compartments. A better understanding of physiological or biochemical phenomena, improve the comprehension of radionuclide behavior in the human body and, in general, more complex compartmental models are proposed, increasing the difficulty of obtaining the analytical solution for the system of first order differential equations. Even with constant transfer rates numerical solutions must be carefully implemented because of almost singular characteristic of the matrix of coefficients. In this work we compare numerical methods with different strategies for ICRP-78 models for Thorium-228 and Uranium-234. The impact of uncertainty in the parameters of the equations is also estimated for local and global truncation errors. (author)

  8. Clinical dosimetry of large shaped 60Co irradiation fields

    International Nuclear Information System (INIS)

    Novotny, J.

    1979-01-01

    The determination is described of absorbed doses in the Alderson-Rando phantom by thermoluminescent dosemeters in patients irradiated with irregularly shaped large-surface fields of Co 60 . In a range of 3 to 5% the measured values correspond to the values calculated with the aid of relations presented by Bukowitz. Non-homogeneity of irradiation when two supradiaphragmatic fields are used and its improvement are discussed. (author)

  9. Improving the accuracy of ionization chamber dosimetry in small megavoltage x-ray fields

    Science.gov (United States)

    McNiven, Andrea L.

    The dosimetry of small x-ray fields is difficult, but important, in many radiation therapy delivery methods. The accuracy of ion chambers for small field applications, however, is limited due to the relatively large size of the chamber with respect to the field size, leading to partial volume effects, lateral electronic disequilibrium and calibration difficulties. The goal of this dissertation was to investigate the use of ionization chambers for the purpose of dosimetry in small megavoltage photon beams with the aim of improving clinical dose measurements in stereotactic radiotherapy and helical tomotherapy. A new method for the direct determination of the sensitive volume of small-volume ion chambers using micro computed tomography (muCT) was investigated using four nominally identical small-volume (0.56 cm3) cylindrical ion chambers. Agreement between their measured relative volume and ionization measurements (within 2%) demonstrated the feasibility of volume determination through muCT. Cavity-gas calibration coefficients were also determined, demonstrating the promise for accurate ion chamber calibration based partially on muCT. The accuracy of relative dose factor measurements in 6MV stereotactic x-ray fields (5 to 40mm diameter) was investigated using a set of prototype plane-parallel ionization chambers (diameters of 2, 4, 10 and 20mm). Chamber and field size specific correction factors ( CSFQ ), that account for perturbation of the secondary electron fluence, were calculated using Monte Carlo simulation methods (BEAM/EGSnrc simulations). These correction factors (e.g. CSFQ = 1.76 (2mm chamber, 5mm field) allow for accurate relative dose factor (RDF) measurement when applied to ionization readings, under conditions of electronic disequilibrium. With respect to the dosimetry of helical tomotherapy, a novel application of the ion chambers was developed to characterize the fan beam size and effective dose rate. Characterization was based on an adaptation of the

  10. Implementation of small field radiotherapy dosimetry for spinal metastase case

    Science.gov (United States)

    Rofikoh, Wibowo, W. E.; Pawiro, S. A.

    2017-07-01

    The main objective of this study was to know dose profile of small field radiotherapy in the spinal metastase case with source axis distance (SAD) techniques. In addition, we evaluated and compared the dose planning of stereotactic body radiation therapy (SBRT) and conventional techniques to measurements with Exradin A16 and Gafchromic EBT3 film dosimeters. The results showed that film EBT3 had a highest precision and accuracy with the average of the standard deviation of ±1.7 and maximum discrepancy of 2.6 %. In addition, the average value of Full Wave Half Maximum (FWHM) and its largest deviation in small field size of 0.8 x 0.8 cm2 are 0.82 cm and 16.3 % respectively, while it was found around 2.36 cm and 3 % for the field size of 2.4 x 2.4 cm2. The comparison between penumbra width and the collimation was around of 37.1 % for the field size of 0.8 x 0.8 cm2, while it was found of 12.4 % for the field size of 2.4 x 2.4 cm2.

  11. Tracking electric field exposure levels through radio frequency dosimetry

    International Nuclear Information System (INIS)

    Ewing, P.D.; Moore, M.R.; Rochelle, R.W.; Thomas, R.S.; Hess, R.A.; Hoffheins, B.S.

    1991-01-01

    The radio-frequency (rf) dosimeter developed by the Oak Ridge National Laboratory is a portable, pocket-sized cumulative-dose recording device designed to detect and record the strengths and durations of electric fields present in the work areas of naval vessels. The device measures an integrated dose and records the electric fields that exceed the permissible levels set by the American National Standards Institute. Features of the rf dosimeter include a frequency range of 30 MHz to 10 GHz and a three-dimensional sensor. Data obtained with the rf dosimeter will be used to determine the ambient field-strength profile for shipboard personnel over an extended time. Readings are acquired and averaged over a 6-min period corresponding to the rise time of the core body temperature. These values are stored for up to 6 months, after which the data are transferred to a computer via the dosimeter's serial port. The rf dosimeter should increase knowledge of the levels of electric fields to which individuals are exposed. 5 refs., 4 figs

  12. Monte Carlo technique applications in field of radiation dosimetry at ENEA radiation protection institute: A Review

    International Nuclear Information System (INIS)

    Gualdrini, G.F.; Casalini, L.; Morelli, B.

    1994-12-01

    The present report summarizes the activities concerned with numerical dosimetry as carried out at the Radiation Protection Institute of ENEA (Italian Agency for New Technologies, Energy and the Environment) on photon dosimetric quantities. The first part is concerned with MCNP Monte Carlo calculation of field parameters and operational quantities for the ICRU sphere with reference photon beams for the design of personal dosemeters. The second part is related with studies on the ADAM anthropomorphic phantom using the SABRINA and MCNP codes. The results of other Monte Carlo studies carried out on electron conversion factors for various tissue equivalent slab phantoms are about to be published in other ENEA reports. The report has been produced in the framework of the EURADOS WG4 (numerical dosimetry) activities within a collaboration between the ENEA Environmental Department and ENEA Energy Department

  13. Characterization of TLD-100 micro-cubes for use in small field dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Peña-Jiménez, Salvador, E-mail: zoid-9861@yahoo.com.mx; Gamboa-deBuen, Isabel, E-mail: gamboa@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 DF (Mexico); Lárraga-Gutiérrez, José Manuel, E-mail: jose.larraga.gtz@gmail.com, E-mail: amanda.garcia.g@gmail.com; García-Garduño, Olivia Amanda, E-mail: jose.larraga.gtz@gmail.com, E-mail: amanda.garcia.g@gmail.com [Laboratorio de Física Médica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Av. Insurgentes Sur 3877, 14269 DF (Mexico)

    2014-11-07

    At present there are no international regulations for the management of millimeter scale fields and there are no suggestions for a reference detector to perform the characterization and dose determination for unconventional radiation beams (small fields) so that the dosimetry of small fields remains an open research field worldwide because these fields are used in radiotherapy treatments. Sensitivity factors and reproducibility of TLD-100 micro-cubes (1×1×1 mm3) were determinate irradiating the dosimeters with a 6 MV beam in a linear accelerator dedicated to radiosurgery at the Instituto Nacional de Neurología y Neurocirugía (INNN). Thermoluminescent response as a function of dose was determined for doses in water between 0.5 and 3 Gy and two field sizes (2×2 cm2 and 10×10 cm2). It was found that the response is linear over the dose range studied and it does not depend on field size.

  14. Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

    International Nuclear Information System (INIS)

    Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

    1976-01-01

    This paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: the spontaneous californium-252 fission neutron spectrum standard field; the thermal-neutron induced uranium-235 fission neutron spectrum standard field; the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN-ΣΣ facilities; the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility; the reference neutron field at the center of the 10% enriched uranium metal, cylindrical, fast critical; the (primary) Intermediate-Energy Standard Neutron Field

  15. Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

    International Nuclear Information System (INIS)

    Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

    1976-10-01

    The paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: (1) the spontaneous californium-252 fission neutron spectrum standard field; (2) the thermal-neutron induced uranium-235 fission neutron spectrum standard field; (3) the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN--ΣΣ facilities; (4) the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility (CFRMF); (5) the reference neutron field at the center of the 10 percent enriched uranium metal, cylindrical, fast critical; and (6) the (primary) Intermediate-Energy Standard Neutron Field

  16. Extremity ring dosimetry intercomparison in reference and workplace fields

    International Nuclear Information System (INIS)

    Ginjaume, M.; Carinou, E.; Donadille, L.; Jankowski, J.; Rimpler, A.; Sans Merce, M.; Vanhavere, F.; Denoziere, M.; Daures, J.; Bordy, J. M.; Itie, C.; Covens, P.

    2008-01-01

    An intercomparison of ring dosemeters has been organised with the aim of assessing the technical capabilities of available extremity dosemeters and focusing on their performance at clinical workplaces with potentially high extremity doses. Twenty-four services from 16 countries participated in the intercomparison. The dosemeters were exposed to reference photon ( 137 Cs) and beta ( 147 Pm, 85 Kr and 90 Sr/ 90 Y) fields together with fields representing realistic exposure situations in interventional radiology (direct and scattered radiation) and nuclear medicine ( 99m Tc and 18 F). It has been found that most dosemeters provided satisfactory measurements of H p (0.07) for photon radiation, both in reference and realistic fields. However, only four dosemeters fulfilled the established requirements for all radiation qualities. The main difficulties were found for the measurement of low-energy beta radiation. Finally, the results also showed a general under-response of detectors to 18 F, which was attributed to the difficulties of the dosimetric systems to measure the positron contribution to the dose. (authors)

  17. Dosimetry methods

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, A.; Kovacs, A.

    2003-01-01

    Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application....

  18. Mixed field dosimetry in the FRN exposure-room

    International Nuclear Information System (INIS)

    Jentzsch, U.

    1976-01-01

    The twin ionization chamber technique, chemical dosimeter systems and silicon diodes have been used to determine the neutron and gamma components of the reactor field in the FRN exposure-room. The knowledge of these components are of fundamental importance for irradiation experiments in the biological research program started at the FRN. The chemical systems and silicon diodes have the advantage of low cost and simple handling. Furthermore, silicon diodes have negligible gamma response and the shift of neutron response with variation of neutron energy spectrum is small. The results of measurements with the different methods have been compared and discussed. (author)

  19. Applications, dosimetry and biological interactions of static and time-varying magnetic fields

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1988-08-01

    The primary topics of this presentation include: (1) the applications of magnetic fields in research, industry, and medical technologies; (2) mechanisms of interaction of static and time-varying magnetic fields with living systems; (3) human health effects of exposure to static and time-varying magnetic fields in occupational, medical, and residential settings; and (4) recent advances in the dosimetry of extremely-low-frequency electromagnetic fields. The discussion of these topics is centered about two issues of considerable contemporary interest: (1) potential health effects of the fields used in magnetic resonance imaging and in vivo spectroscopy, and (2) the controversial issue of whether exposure to extremely-low-frequency (ELF) electromagnetic fields in the home and workplace leads to an elevated risk of cancer. 11 refs

  20. Scientific days on electromagnetic fields: from dosimetry to human health - Conference proceedings; Journees scientifiques - Champs electromagnetiques: de la dosimetrie a la sante humaine - Recueil des resumes et presentations

    Energy Technology Data Exchange (ETDEWEB)

    Wiart, J.; Ghanmi, A.; Picon, O.; Conil, E.; Varsier, N.; Hadjem, A.; Sudret, B.; Magne, I.; Souques, M.; Gaudaire, F.; De Seze, R.; Jawad, O.; Lautru, D.; Dricot, J.M.; Horlin, F.; De Doncker, P.; Drissaoui, A.; Musy, F.; Nicolas, L.; Perrussel, R.; Scorretti, R.; Voyer, D.; Jala, M.; Moulines, E.; Levy-Leduc, C.; Mahfouz, Z.; Gati, A.; Fouad Hanna, V.; Leveque, P.; Arnaud-Cormos, D.; Zhadobov, M.; Jarrige, P.; Gaborit, G.; Kohler, S.; Ticaud, N.; Duvillaret, L.; Guelilia, Z.; Loison, R.; Gillard, R.; Laisne, A.; Favet, D.; Benadhira, R.; Mir, L.; Nadi, M.; Kourtiche, D.; Gazeau, F.; Wilhelm, C.; Delemotte, L.; Breton, M.; Tarek, M.; Marc-Vergnes, J.P.; Yardin, C.; Perrin, A.; Le Drean, Y.; Sauleau, R.; Lambrozo, J.; Selmaoui, B.; Ghosn, R.; Thuroczy, G.; Villegier, A.S.; Loos, N.; Brenet-Dufour, V.; Liabeuf, S.; Bach, V.; Moretti, D.; Lewis, N.; Garenne, A.; Poulletier De Gannes, F.; Haro, E.; Lagroye, I.; Bornat, Y.; Boutaib, Y.; Saighi, S.; Renaud, S.; Veyre, B.; Schuz, J.; Deltour, I.; Van Deventer, E.; Vecchia, P.; Merckel, O.; Bellaouel, A.; Demaret, P.; Donati, P.; Jovanovic, D.; Chauvin, S.; Desreumaux, J.P.; Fouquet, L.; Picard, D.; Massardier-Pilonchery, A.; Hours, M.; Bergeret, A.; Person, C.; Toutain, Y.; Butet, R.; Berrahma, K.; Balderelli, I.; Stelmaszyk, V.; Cretallaz, C.; Lamproglou, I.; Amourette, C.; Diserbo, M.; Fauquette, W.; Martigne, P.; Collin, A.; Lagroye, I.; Ait Aissa, S.; Hurtier, A.; Taxile, M.; Le Montagner, L.; Athane, A.; Duleu, S.; Percherancier, Y.; Geffard, M.; Ruffie, G.; Billaudel, B.; Veyret, B.; Pelletier, A.; Delanaud, S.; Libert, J.P.; Schunck, T.; Bieth, F.; Soubere Mahamoud, Y.; Le Quement, C.; Ferrand, G.; Le Guevel, R.; Carton, P.H.; Luong, M.; Tanvir, S.; Selmaoui, B.; Silva Pires-Antonietti, V.; Sonnet, P.; Pulvin, S.; Kuster, O.; Tetelin, C.

    2012-04-15

    This document brings together the available presentations (articles and slides) given at the URSI scientific days on electromagnetic fields: dosimetry, peoples' exposure, biological and health risks, risk management, and medical uses. 48 presentations are compiled in this document and deal with: 1 - Stochastic dosimetry: variability challenge; 2 - How to estimate the exposure to 50/60 Hz magnetic field in an epidemiological study?; 3 - Joint analysis of population exposure and radio coverage of GSM and UMTS mobile phone networks; 4 - Study of the specific energy absorption rate (SAR) sensitiveness to phone positions near the head for 2 GSM mobile phones; 5 - Statistical Study of SAR under Wireless Channel - Exposure in Indoor Environment; 6 - Uncertainty propagation in numerical dosimetry: how to reduce calculation costs?; 7 - Use of a simplified pregnant woman model for foetus exposure analysis; 8 - SAR estimation using multi-exposure with a mobile phone; 9 - State-of-the-art in experimental dosimetry (RF and pulses); 10 - Mm-waves dosimetry: issues, stakes and actual solutions; 11 - Use of DG-FDTD for a dosimetry calculation in a strongly multi-scale problem: determination of the eye-SAR near a HF/VHF vehicle-borne source; 12 - Dosimetric measurements with a fiber-type electro-optical sensor; 13 - Partial experimental evaluation of basic restrictions in the HF/VHF range; 14 - Repetitive trans-cranial magnetic stimulation Stimulation (rTMS) in psychiatry: present day situation and perspectives; 15 - Medical applications of electric fields; 16 - Measurements for life: new perspectives? 17 - Nano-particles and magnetic stimuli for medical imaging and therapy; 18 - Molecular Insights into electroporation and siRNA electro-transfer through model cell membranes; 19 - State of knowledge on electromagnetic fields hypersensitivity (HS-CEM); 20 - Experimentation methodology: from results to interpretation; 22 - Mm waves - update on biological effects at 40-60 GHz; 23

  1. The relationship between anatomically correct electric and magnetic field dosimetry and publishe delectric and magnetic field exposure limits.

    Science.gov (United States)

    Kavet, Robert; Dovan, Thanh; Reilly, J Patrick

    2012-12-01

    Electric and magnetic field exposure limits published by International Commission for Non-Ionizing Radiation Protection and Institute of Electrical and Electronics Engineers are aimed at protection against adverse electrostimulation, which may occur by direct coupling to excitable tissue and, in the case of electric fields, through indirect means associated with surface charge effects (e.g. hair vibration, skin sensations), spark discharge and contact current. For direct coupling, the basic restriction (BR) specifies the not-to-be-exceeded induced electric field. The key results of anatomically based electric and magnetic field dosimetry studies and the relevant characteristics of excitable tissue were first identified. This permitted us to assess the electric and magnetic field exposure levels that induce dose in tissue equal to the basic restrictions, and the relationships of those exposure levels to the limits now in effect. We identify scenarios in which direct coupling of electric fields to peripheral nerve could be a determining factor for electric field limits.

  2. The practical application of scintillation dosimetry in small-field photon-beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Burke, Elisa; Poppinga, Daniela; Schoenfeld, Andreas A.; Poppe, Bjoern; Looe, Hui Khee [Oldenburg Univ. (Germany). Univ. Clinic for Medical Radiation Physics; Harder, Dietrich [Goettingen Univ. (Germany). Medical Physics and Biophysics

    2017-07-01

    Plastic scintillation detectors are a new instrument of stereotactic photon-beam dosimetry. The clinical application of the plastic scintillation detector Exradin W1 at the Siemens Artiste and Elekta Synergy accelerators is a matter of current interest. In order to reduce the measurement uncertainty, precautions have to be taken with regard to the geometrical arrangement of the scintillator, the light-guide fiber and the photodiode in the radiation field. To determine the ''Cerenkov light ratio'' CLR with a type A uncertainty below 1%, the Cerenkov calibration procedure for small-field measurements based on the two-channel spectral method was used. Output factors were correctly measured with the W1 for field sizes down to 0.5 x 0.5 cm{sup 2} with a type A uncertainty of 1.8%. Measurements of small field dose profiles and percentage depth dose curves were carried out with the W1 using automated water phantom profile scans, and a type A uncertainty for dose maxima of 1.4% was achieved. The agreement with a synthetic diamond detector (microDiamond, PTW Freiburg) and a plane parallel ionization chamber (Roos chamber, PTW Freiburg) in relative dose measurements was excellent. In oversight of all results, the suitability of the plastic scintillation detector Exradin W1 for clinical dosimetry under stereotactic conditions, in particular the tried and tested procedures for CLR determination, output factor measurement and automated dose profile scans in water phantoms, have been confirmed.

  3. TH-CD-BRA-07: MRI-Linac Dosimetry: Parameters That Change in a Magnetic Field

    International Nuclear Information System (INIS)

    O’Brien, D. J.; Sawakuchi, G. O.

    2016-01-01

    Purpose: In MRI-linac integrated systems, the presence of the magnetic (B-)field has a large impact of the dose-distribution and the dose-responses of detectors; yet established protocols and previous experience may lead to assumptions about the commissioning process that are no longer valid. This study quantifies parameters that change when performing dosimetry with an MRI-linac including beam quality specifiers and the effective-point-of-measurement (EPOM) of ionization chambers. Methods: We used the Geant4 Monte Carlo code for this work with physics parameters that pass the Fano cavity test to within 0.1% for the simulated conditions with and without a 1.5 T B-field. A point source model with the energy distribution of an MRI-linac beam was used with and without the B-field to calculate the beam quality specifiers %dd(10)× and TPR 20 10 , the variation of chamber response with orientation and the how the B-field affects the EPOM of ionization chambers by comparing depth-dose curves calculated in water to those generated by a model PTW30013 Farmer chamber. Results: The %dd(10)× changes by over 2% in the presence of the B-field while the TPR 20 10 is unaffected. Ionization chamber dose-response is known to depend on the orientation w.r.t. the B-field, but two alternative perpendicular orientations (anti-parallel to each other) also differ in dose-response by over 1%. The B-field shifts the EPOM downstream (closer to the chamber center) but it is also shifted laterally by 0.27 times the chamber’s cavity radius. Conclusion: The EPOM is affected by the B-field and it even shifts laterally. The relationship between %dd(10)× and the Spencer-Attix stopping powers is also changed. Care must be taken when using chambers perpendicular to the field as the dose-response changes depending on which perpendicular orientation is used. All of these effects must be considered when performing dosimetry in B-fields and should be accounted for in future dosimetry protocols. This

  4. TH-CD-BRA-07: MRI-Linac Dosimetry: Parameters That Change in a Magnetic Field

    Energy Technology Data Exchange (ETDEWEB)

    O’Brien, D. J.; Sawakuchi, G. O. [The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: In MRI-linac integrated systems, the presence of the magnetic (B-)field has a large impact of the dose-distribution and the dose-responses of detectors; yet established protocols and previous experience may lead to assumptions about the commissioning process that are no longer valid. This study quantifies parameters that change when performing dosimetry with an MRI-linac including beam quality specifiers and the effective-point-of-measurement (EPOM) of ionization chambers. Methods: We used the Geant4 Monte Carlo code for this work with physics parameters that pass the Fano cavity test to within 0.1% for the simulated conditions with and without a 1.5 T B-field. A point source model with the energy distribution of an MRI-linac beam was used with and without the B-field to calculate the beam quality specifiers %dd(10)× and TPR{sup 20}{sub 10}, the variation of chamber response with orientation and the how the B-field affects the EPOM of ionization chambers by comparing depth-dose curves calculated in water to those generated by a model PTW30013 Farmer chamber. Results: The %dd(10)× changes by over 2% in the presence of the B-field while the TPR{sup 20}{sub 10} is unaffected. Ionization chamber dose-response is known to depend on the orientation w.r.t. the B-field, but two alternative perpendicular orientations (anti-parallel to each other) also differ in dose-response by over 1%. The B-field shifts the EPOM downstream (closer to the chamber center) but it is also shifted laterally by 0.27 times the chamber’s cavity radius. Conclusion: The EPOM is affected by the B-field and it even shifts laterally. The relationship between %dd(10)× and the Spencer-Attix stopping powers is also changed. Care must be taken when using chambers perpendicular to the field as the dose-response changes depending on which perpendicular orientation is used. All of these effects must be considered when performing dosimetry in B-fields and should be accounted for in future

  5. Discussions in symposium 'neutron dosimetry in neutron fields - from detection techniques to medical applications'

    International Nuclear Information System (INIS)

    Tanimura, Y.; Sato, T.; Kumada, H.; Terunuma, T.; Sakae, T.; Harano, H.; Matsumoto, T.; Suzuki, T.; Matsufuji, N.

    2008-01-01

    Recently the traceability system (JCSS) of neutron standard based on the Japanese law 'Measurement Act' has been instituted. In addition, importance of the neutron dose evaluation has been increasing in not only the neutron capture medical treatment but also the proton or heavy particle therapy. Against such a background, a symposium 'Neutron dosimetry in neutron fields - From detection techniques to medical applications-' was held on March 29, 2008 and recent topics on the measuring instruments and their calibration, the traceability system, the simulation technique and the medical applications were introduced. This article summarizes the key points in the discussion at the symposium. (author)

  6. Biokinetics of radiotellurium in rats

    International Nuclear Information System (INIS)

    Nishimura, Y.; Sahoo, S.K.; Kim, S.; Homma-Takeda, S.; Watanabe, Y.; Inaba, J.

    2003-01-01

    Radiotellurium is present in the environment primarily due to its release during nuclear reactor accidents. Little is known of tellurium metabolism in juveniles, although the element is relatively abundant and has a number of industrial uses. A biokinetic study of radiotellurium in rats was done using gamma-ray counting. Wistar strain rats were used to determine the uptake of H 2 123 Te m O 3 by the whole-body retention of juvenile rats and the conceptus in relation to its gestational stages, by measurements in the placenta, fetal membranes, fetal fluid, and fetus. The whole-body retention of 123 Te m in juvenile rats was higher than that of adult rats. The relative concentration in the placenta and fetal membranes was higher than in the fetus. No activity was observed in the fetal fluid. These results indicate that the placenta and fetal membranes play significant roles as barriers to the transfer of 123 Te m into the fetus. The ratio, relative concentration in fetus/relative concentration in mother (C F /C M ), was calculated. The C F /C M ratio was dependent on the stage of gestation and ranged from 0.2 to 0.5. A little 123 Te m was transferred to the suckling rats through the mother's milk when the isotope was administered intravenously to the mother. (author)

  7. Biokinetic model for 137 Cs

    International Nuclear Information System (INIS)

    Melo, Dunstana Rabelo de

    1995-01-01

    The main objective of this work was to provide a realistic biokinetic model for 137 Cs metabolism. This model was based on the retention of cesium in 57 people contaminated in the Goiania accident, ages 1 to 73 y old, complemented by data obtained in an experiment with beagle dogs, and data taken from the open literature. Cesium is distributed among all tissues and organs of the body. Its main retention site is the skeletal muscle tissue. Mathematically, cesium retention in the body may be described by a sum of three terms exponential equation. The first term represents the fraction which is rapidly eliminated in urine. This fraction is weight dependent (negative correlation). The second term represents the retention of cesium in tissues and organs of the body. For children and adolescents, the second term biological half-life is a function of the weight. For adults, it is correlated with sex. Men present a higher retention of cesium than women. The third term correspond to a retention fraction of the order of 0,1% of the initial body burden. It is characterized by a very long half-life and represents a subcellular retention of cesium in the skeletal muscle tissue. During pregnancy the transfer factor from the mother to the fetus is correlated to the amount of cesium in the blood and it is equal to 1, if the intake of cesium occurs pregnancy. (author)

  8. Workplace monitoring of mixed neutron-photon radiation fields and its contribution to external dosimetry

    International Nuclear Information System (INIS)

    Schuhmacher, H.

    2011-01-01

    Workplace monitoring is a common procedure for determining measures for routine radiation protection in a particular working environment. For mixed radiation fields consisting of neutrons and photons, it is of increased importance because it contributes to the improved accuracy of individual monitoring. An example is the determination of field-specific correction factors, which can be applied to the readings of personal dosemeters. This paper explains the general problems associated with individual dosimetry of neutron radiation, and describes the various options for workplace monitoring. These options cover a range from the elaborate field characterisation using transport calculations or spectrometers to the simpler approach using area monitors. Examples are given for workplaces in nuclear industry, at particle accelerators and at flight altitudes. (authors)

  9. SU-F-T-445: Effect of Triaxial Cables and Microdetectors in Small Field Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Das, I; Andersen, A [Indiana University- School of Medicine, Indianapolis, IN (United States)

    2016-06-15

    Purpose: Advances in radiation treatment especially with smaller fields used in SRS, Gamma knife, Tomotherapy, Cyberknife, and IMRT, require a high degree of precision especially with microdetectors for small field dosimetry (Das et al, Med Ph, 35, 206, 2008; Alfonso et al, Med Phys, 35, 5179, 2008). Due to small signal, the triaxial cable becomes critical in terms of signal to noise ratio (SNR) which is studied with microdetectors. Methods: Six high quality triaxial cables, 9.1 meters long from different manufacturers without any defects were acquired along with 5 most popular microdetectors (microdiamond, plastic scintillators, SRS-diode, edge-diode and pinpoint). A dedicated electrometer was used for each combination except W1 which has its own supermax electrometer. A 6MV photon beam from Varian True beam with 100 MU at a 600 MU/min was used. Measurements were made at a depth of 5 cm in water phantom. Field sizes were varied from 0.5 cm to 10 cm square fields. Readings were taken with combination of cables and microdetectors. Results: Signal is dependent on the quality of the connectors, cables and types of microdetector. The readings varied from nC to pC depending on the type of microdetector. The net signal, S, (Sc-Sn), where Sc is signal with chamber and Sn is without chamber is a linear function of sensitive volume, v; (S = α+β•V), where α and β are constants. The standard deviation (SD) in 3 sets of reading with each combination of cable-detector was extremely low <0.02%. As expected the SD is higher in small fields (<3cm). Maximum estimated error was only ±0.2% in cables-detector combinations. Conclusion: The choice of cables has relatively small effect (±0.2%) with microdosimeter and should be accounted in overall error estimation in k value that is needed to convert ratio of reading to dose in small field dosimetry.

  10. SU-F-T-445: Effect of Triaxial Cables and Microdetectors in Small Field Dosimetry

    International Nuclear Information System (INIS)

    Das, I; Andersen, A

    2016-01-01

    Purpose: Advances in radiation treatment especially with smaller fields used in SRS, Gamma knife, Tomotherapy, Cyberknife, and IMRT, require a high degree of precision especially with microdetectors for small field dosimetry (Das et al, Med Ph, 35, 206, 2008; Alfonso et al, Med Phys, 35, 5179, 2008). Due to small signal, the triaxial cable becomes critical in terms of signal to noise ratio (SNR) which is studied with microdetectors. Methods: Six high quality triaxial cables, 9.1 meters long from different manufacturers without any defects were acquired along with 5 most popular microdetectors (microdiamond, plastic scintillators, SRS-diode, edge-diode and pinpoint). A dedicated electrometer was used for each combination except W1 which has its own supermax electrometer. A 6MV photon beam from Varian True beam with 100 MU at a 600 MU/min was used. Measurements were made at a depth of 5 cm in water phantom. Field sizes were varied from 0.5 cm to 10 cm square fields. Readings were taken with combination of cables and microdetectors. Results: Signal is dependent on the quality of the connectors, cables and types of microdetector. The readings varied from nC to pC depending on the type of microdetector. The net signal, S, (Sc-Sn), where Sc is signal with chamber and Sn is without chamber is a linear function of sensitive volume, v; (S = α+β•V), where α and β are constants. The standard deviation (SD) in 3 sets of reading with each combination of cable-detector was extremely low <0.02%. As expected the SD is higher in small fields (<3cm). Maximum estimated error was only ±0.2% in cables-detector combinations. Conclusion: The choice of cables has relatively small effect (±0.2%) with microdosimeter and should be accounted in overall error estimation in k value that is needed to convert ratio of reading to dose in small field dosimetry.

  11. Dimer of the peptide cycle (Ar-Gly-Asp-D-Phe-Lys) radiolabeled with {sup 99m}Tc for the integrin s over-expression image: formulation, biokinetics and dosimetry; Dimero del peptido ciclo(Arg-Gly-Asp-D-Phe-Lys) radiomarcado con {sup 99m}Tc para la imagen de sobre-expresion de integrinas: formulacion, biocinetica y dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz A, Z.

    2013-07-01

    In breast cancer, α(v)β(3) and/or α(v)β(5) integrin s are over-expressed in both endothelial and tumour cells. Radiolabeled peptides based on the RGD (Arg-Gly-Asp) sequence are radiopharmaceuticals with high affinity and selectivity for those integrin s. The RGD-dimer peptide (E-[c(RGDfK)]{sub 2}) radiolabeled with {sup 99m}Tc has been reported as a radiopharmaceutical with 10-fold higher affinity for the α(v)β(3) integrin as compared to the RGD-monomer. EDDA (Ethylenediamine-N,N-diacetic acid) is a hydrophilic molecule that may favours renal excretion when used as coligand in the {sup 99m}Tc labelling of HYNIC-peptides and can easily be formulated in a lyophilized kit. Aim: Establish a biokinetic model for {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} prepared from lyophilized kits and evaluate the dosimetry as breast cancer imaging agent. Methods: {sup 99m}Tc labelling was performed by addition of sodium pertechnetate solution and 0.2 M phosphate buffer ph 7.0 to a lyophilized formulation containing E-[c(RGDfK)]{sub 2}, EDDA, tricine, mannitol and stannous chloride. Radiochemical purity was evaluated by reversed phase HPLC and ITLC-SG analyses. Stability studies in human serum were carried out by size-exclusion HPLC. In-vitro cell uptake was tested using breast cancer cells (MCF7, T47D and MDA-MB-231) with blocked and non-blocked receptors. Biodistribution and tumour uptake were determined in MCF7 tumour-bearing nude mice with blocked and non-blocked receptors, and images were obtained using a micro-SPECT/CT. Whole-body images from seven healthy women were acquired at 1, 3, 6 and 24 h after {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} administration obtained with radiochemical purities of >94 %. Regions of interest (ROIs) were drawn around source organs on each time frame. Each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} time-activity curves in each

  12. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  13. Personal dosimetry in a mixed field of high energy muons and neutrons

    International Nuclear Information System (INIS)

    Cossairt, J.D.; Elwyn, A.J.

    1986-11-01

    High energy accelerators quite often emit muons. These particles behave in matter as would heavy electrons and are thus difficult to attenuate with shielding in many situations. Hence, these muons can be a source of radiation exposure to personnel and suitable methods of measuring the absorbed dose received to these people is obviously required. In practical situations, such muon radiation fields are often mixed with neutrons, well-known to be an even more troublesome particle species with respect to dosimetry. In this paper, we report on fluence measurements made in such a mixed radiation field and a comparison of dosimeter responses. We conclude that commercial self-reading dosimeters and film badges provided an adequate measure of the absorbed dose due to muons

  14. Measurements of Integral Cross Section Ratios in Two Dosimetry Benchmark Neutron Fields

    International Nuclear Information System (INIS)

    Fabry, A.; Czock, K.H.

    1974-12-01

    In the frame of a current interlaboratory effort devoted to the standardization of fuels and materials neutron dosimetry, the 103 Rh(n,n') 103m Rh and 58 Ni(n,p) 58 Co integral cross sections have been accurately measured relatively to the 115 In(n,n') 115m In cross section in the 235 U thermal dission neutron spectrum and in the MOLΣΣ Intermediate-Energy Standard Neutron field. In this last neutron field, the data are related also to the 235 U(n,f) cross section. The measurements are extensively documented and the results briefly compared to literature. Most noticeably, decisive support is provided for the selection of a specific 103 Rh(n,n') 103m Rh differential-energy cross section among the existing, conflicting data. (author)

  15. Measurements of integral cross section ratios in two dosimetry benchmark neutron fields

    International Nuclear Information System (INIS)

    Fabry, A.; Czock, K.H.

    1974-12-01

    In the frame of a current interlaboratory effort devoted to the standardization of fuels and materials neutron dosimetry, the 103 Rh(n,n') 103m Rh and 58 Ni(n,p) 58 Co integral cross sections have been accurately measured relatively to the 115 In(n,n') 115m In cross section in the 235 U thermal fission neutron spectrum and in the MOL-ΣΣ intermediate-energy standard neutron field. In this last neutron field, the data are related also to the 235 U(n,f) cross section. The measurements are extensively documented and the results briefly compared to literature. Most noticeably, decisive support is provided for the selection of a specific 103 Rh(n,n') 103m Rh differential-energy cross section among the existing, conflicting data. (author)

  16. Performance of neutron and gamma personnel dosimetry in mixed radiation fields

    International Nuclear Information System (INIS)

    Swaja, R.E.; Sims, C.S.

    1981-01-01

    From 1974 to 1980, six personnel dosimetry intercomparison studies (PDIS) were conducted at the Oak Ridge National Laboratory (ORNL) to evaluate the performance of personnel dosimeters in a variety of neutron and gamma fields produced by operating the Health Physics Research Reactor (HPRR) in the steady state mode with and without spectral modifying shields. A total of 58 different organizations participated in these studies which produced approximately 2000 measurements of neutron and gamma dose equivalents on anthropomorphic phantoms for five different reactor spectra. Based on these data, the relative performance of three basic types of neutron dosimeters [nuclear emulsion film, thermoluminescent (TLD), and track-etch] and two basic types of gamma dosimeters (film and TLD) in mixed radiation fields was assessed

  17. Measurements of integral cross section ratios in two dosimetry benchmark neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, A [CEN-SCK, Mol (Belgium); Czock, K H [International Atomic Energy Agency, Laboratory Seibersdorf, Vienna (Austria)

    1974-12-01

    In the frame of a current interlaboratory effort devoted to the standardization of fuels and materials neutron dosimetry, the {sup 103}Rh(n,n'){sup 103m}Rh and {sup 58}Ni(n,p){sup 58}Co integral cross sections have been accurately measured relatively to the {sup 115}In(n,n'){sup 115m} In cross section in the {sup 235}U thermal fission neutron spectrum and in the MOL-{sigma}{sigma} intermediate-energy standard neutron field. In this last neutron field, the data are related also to the {sup 235}U(n,f) cross section. The measurements are extensively documented and the results briefly compared to literature. Most noticeably, decisive support is provided for the selection of a specific {sup 103}Rh(n,n'){sup 103m}Rh differential-energy cross section among the existing, conflicting data. (author)

  18. Measurements of Integral Cross Section Ratios in Two Dosimetry Benchmark Neutron Fields

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, A. [CEN-SCK, Mol (Belgium); Czock, K. H. [International Atomic Energy Agency, Vienna (Austria)

    1974-12-15

    In the frame of a current interlaboratory effort devoted to the standardization of fuels and materials neutron dosimetry, the {sup 103}Rh(n,n'){sup 103m}Rh and {sup 58}Ni(n,p){sup 58}Co integral cross sections have been accurately measured relatively to the {sup 115}In(n,n'){sup 115m}In cross section in the {sup 235}U thermal dission neutron spectrum and in the MOL{Sigma}{Sigma} Intermediate-Energy Standard Neutron field. In this last neutron field, the data are related also to the {sup 235}U(n,f) cross section. The measurements are extensively documented and the results briefly compared to literature. Most noticeably, decisive support is provided for the selection of a specific {sup 103}Rh(n,n'){sup 103m}Rh differential-energy cross section among the existing, conflicting data. (author)

  19. Dosimetry with tissue-equivalent ionisation chambers in fast neutron fields for biomedical applications

    International Nuclear Information System (INIS)

    Zoetelief, J.; Broerse, J.J.

    1983-01-01

    The use of calibrated tissue-equivalent (TE) ionisation chambers is commonly considered to be the most practical method for total absorbed dose determinations in mixed neutron-photon fields for biomedical applications. The total absorbed dose can be derived from the charge produced within the cavity of an ionisation chamber employing a number of physical parameters. To arrive at the charge produced in the cavity several correction factors have to be introduced which are related to the operational characteristics of the chambers. Information on the operational characteristics of four TE ionisation chambers is presented in relation to ion collection, density and composition of gas in the cavity, wall thickness and effective point of measurement. In addition, some recent results from an ionisation chamber operated at high gas pressures are presented. The total absorbed doses derived from TE ionisation chambers show agreement within the uncertainty limits with results from other independent dosimetry methods, i.e., differential fluence measurements and a TE calorimeter. Conscientious experimentation and a common data base can provide dosimetry results with TE ionisation chambers with variations of less than +-2%. (author)

  20. Field monitoring versus individual miner dosimetry of radon daughter products in mines.

    Science.gov (United States)

    Domański, T; Kluszczyński, D; Olszewski, J; Chruscielewski, W

    1989-01-01

    The paper presents the results realised simultaneously by two different and independent systems of measurement of an assessment of miners' exposure to radon daughter products which naturally occur in the air of mines. The first one, called the Air Sampling System (ASS), was based on the field monitoring of radon progeny in air, the second one, called the Individual Dosimetry System (IDS), was based on the individual dosimeters worn by miners. Experimental comparison of these two systems has been conducted for six years in eleven Polish underground metal-ore mines. This study reveals that no correlation exists between the concentration and annual miners' exposures evaluated by the ASS and IDS. The ratio ASS/IDS for mine population varies from 11.0 to 0.14 in respect of annual concentration means, and in respect to annual exposures, this ratio varies from 4.5 to 0.14. The conclusion to be drawn from six years' observation and comparison of both systems is that correct and true evaluation of miners' exposure to radon progeny can be made only by the use of the Individual Dosimetry System, since the Air Sampling System is too sensitive and too dependent on the Strategy of sampling and its radiation.

  1. Consistent biokinetic models for the actinide elements

    International Nuclear Information System (INIS)

    Leggett, R.W.

    2001-01-01

    The biokinetic models for Th, Np, Pu, Am and Cm currently recommended by the International Commission on Radiological Protection (ICRP) were developed within a generic framework that depicts gradual burial of skeletal activity in bone volume, depicts recycling of activity released to blood and links excretion to retention and translocation of activity. For other actinide elements such as Ac, Pa, Bk, Cf and Es, the ICRP still uses simplistic retention models that assign all skeletal activity to bone surface and depicts one-directional flow of activity from blood to long-term depositories to excreta. This mixture of updated and older models in ICRP documents has led to inconsistencies in dose estimates and interpretation of bioassay for radionuclides with reasonably similar biokinetics. This paper proposes new biokinetic models for Ac, Pa, Bk, Cf and Es that are consistent with the updated models for Th, Np, Pu, Am and Cm. The proposed models are developed within the ICRP's generic model framework for bone-surface-seeking radionuclides, and an effort has been made to develop parameter values that are consistent with results of comparative biokinetic data on the different actinide elements. (author)

  2. Worldwide bioassay data resources for plutonium/americium internal dosimetry studies

    International Nuclear Information System (INIS)

    Miller, G.; Bertelli, L.; Little, T.; Guilmette, R.; Riddell, T.; Filipy, R.

    2005-01-01

    Full text: Biokinetic models are the scientific underpinning of internal dosimetry. These models describe how materials of interest taken into the body by various routes (for example inhalation) are transported through the body, allowing the modelling of bioassay measurements and the estimation of radiation dose. The International Commission on Radiation Protection (ICRP) publishes biokinetic models for use in internal dosimetry. These models represent the consensus judgement of a committee of experts, based on human and animal data. Nonetheless, it is important to validate biokinetic models using directly applicable data, in a scientifically transparent manner, especially for internal dosimetry research purposes (as opposed to radiation protection), as in epidemiology studies. Two major goals would be to determine individual variations of model parameters for the purpose of assessing this source of uncertainty in internal dose calculations, and to determine values of workplace specific parameters (such as particle solubility in lung fluids) for different representative workplaces. Furthermore, data on the observed frequency of intakes under various conditions can be used in the interpretation of bioassay data. All of the above may be couched in the terminology of Bayesian statistical analysis and amount to the determination of the Bayesian prior probability distributions needed in a Bayesian interpretation of bioassay data. The authors have direct knowledge of several significant databases of plutonium/americium bioassay data (including autopsy data). The purpose of this paper is to acquaint the worldwide community with these resources and to invite others who may know of other such databases to participate with us in a publication that would document the content, form, and the procedures for seeking access to these databases. These databases represent a tremendous scientific resource in this field. Examples of databases known to the authors include: the

  3. The relationship between anatomically correct electric and magnetic field dosimetry and published electric and magnetic field exposure limits

    International Nuclear Information System (INIS)

    Kavet, R.; Dovan, T.; Patrick Reilly, J.

    2012-01-01

    Electric and magnetic field exposure limits published by International Commission for Non-Ionizing Radiation Protection and Inst. of Electrical and Electronics Engineers are aimed at protection against adverse electro-stimulation, which may occur by direct coupling to excitable tissue and, in the case of electric fields, through indirect means associated with surface charge effects (e.g. hair vibration, skin sensations), spark discharge and contact current. For direct coupling, the basic restriction (BR) specifies the not-to-be-exceeded induced electric field. The key results of anatomically based electric and magnetic field dosimetry studies and the relevant characteristics of excitable tissue were first identified. This permitted us to assess the electric and magnetic field exposure levels that induce dose in tissue equal to the basic restrictions, and the relationships of those exposure levels to the limits now in effect. We identify scenarios in which direct coupling of electric fields to peripheral nerve could be a determining factor for electric field limits. (authors)

  4. Bubble detectors as a tool of the dosimetry and microdosimetry in neutron fields

    International Nuclear Information System (INIS)

    Spurny, F.; Vlcek, B.; Rannou, A.

    1998-01-01

    Two types of bubble detector were studied: the Bubble Damage Neutron Detector (BDND) and the Superheated Drop Detector (SDD). The detectors were tested in neutron beams and fields. The relative response of the detectors varied with the average neutron energy. The response of SDD 100 started to decrease at higher energies than for BDND's, at 100 keV it was only about 1/4 of the response to AmBe neutrons. The responses of SDD 1000 and SDD 6000 decreased with the average neutron energy in a rather similar way. Starting from the AmLi source they represented less than 0.1 of the response to AmBe neutrons. Their response to high energy neutrons was practically the same as to AmBe neutrons. This is important for individual air crew dosimetry on board aircraft. (M.D.)

  5. TU-F-BRE-05: Experimental Determination of K Factor in Small Field Dosimetry

    International Nuclear Information System (INIS)

    Das, I; Akino, Y; Francescon, P

    2014-01-01

    Purpose: Small-field dosimetry is challenging due to charged-particle disequilibrium, source occlusion and more importantly finite size of detectors. IAEA/AAPM has published approach to convert detector readings to dose by k factor. Manufacturers have been trying to provide various types of micro-detectors that could be used in small fields. However k factors depends on detector perturbations and are derived using Monte Carlo simulation. PTW has introduced a microDiamond for small-field dosimetry. An experimental approach is presented to derive the k factor for this detector. Methods: PTW microDiamond is a small volume detector with 1.1 mm radius and 1.0 micron thick synthetic diamond. Output factors were measured from 1×1cm2 to 12×12 cm2 on a Varian machine at various depths using various micro-detectors with published k factors. Dose is calculated as reading * K. Assuming k factor is accurate, output factor should be identical with every micro-detectors. Hence published k values (Francescon et al Med Phys 35, 504-513,2008) were used to covert readings and then output factors were computed. Based on the converged curve from other detectors, k factor for microDiamond was computed versus field size. Results: Traditional output factors as ratio of readings normalized to 10×10 cm2 differ significantly for micro-detectors for fields smaller than 3×3 cm2 which are now being used extensively. When readings are converted to dose, the output factor is independent of detector. Based on this method, k factor for microDiamond was estimated to be nearly constant 0.993±0.007 over varied field sizes. Conclusion: Our method provides a unique opportunity to determine the k factor for any unknown detector. It is shown that even though k factor depends on machine type due to focal spot, however for fields ≥1×1 cm2 this method provides accurate evaluation of k factor. Additionally microDiamond could be used with assumption that k factor is nearly unity

  6. Is the PTW 60019 microDiamond a suitable candidate for small field reference dosimetry?

    Science.gov (United States)

    De Coste, Vanessa; Francescon, Paolo; Marinelli, Marco; Masi, Laura; Paganini, Lucia; Pimpinella, Maria; Prestopino, Giuseppe; Russo, Serenella; Stravato, Antonella; Verona, Claudio; Verona-Rinati, Gianluca

    2017-09-01

    A systematic study of the PTW microDiamond (MD) output factors (OF) is reported, aimed at clarifying its response in small fields and investigating its suitability for small field reference dosimetry. Ten MDs were calibrated under 60Co irradiation. OF measurements were performed in 6 MV photon beams by a CyberKnife M6, a Varian DHX and an Elekta Synergy linacs. Two PTW silicon diodes E (Si-D) were used for comparison. The results obtained by the MDs were evaluated in terms of absorbed dose to water determination in reference conditions and OF measurements, and compared to the results reported in the recent literature. To this purpose, the Monte Carlo (MC) beam-quality correction factor, kQMD , was calculated for the MD, and the small field output correction factors, k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} , were calculated for both the MD and the Si-D by two different research groups. An empirical function was also derived, providing output correction factors within 0.5% from the MC values calculated for all of the three linacs. A high reproducibility of the dosimetric properties was observed among the ten MDs. The experimental kQMD values are in agreement within 1% with the MC calculated ones. Output correction factors within  +0.7% and  -1.4% were obtained down to field sizes as narrow as 5 mm. The resulting MD and Si-D field factors are in agreement within 0.2% in the case of CyberKnife measurements and 1.6% in the other cases. This latter higher spread of the data was demonstrated to be due to a lower reproducibility of small beam sizes defined by jaws or multi leaf collimators. The results of the present study demonstrate the reproducibility of the MD response and provide a validation of the MC modelling of this device. In principle, accurate reference dosimetry is thus feasible by using the microDiamond dosimeter for field sizes down to 5 mm.

  7. Dosimetry; La dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Le Couteulx, I.; Apretna, D.; Beaugerie, M.F. [Electricite de France (EDF), 75 - Paris (France)] [and others

    2003-07-01

    Eight articles treat the dosimetry. Two articles evaluate the radiation doses in specific cases, dosimetry of patients in radiodiagnosis, three articles are devoted to detectors (neutrons and x and gamma radiations) and a computer code to build up the dosimetry of an accident due to an external exposure. (N.C.)

  8. Environmental dosimetry

    International Nuclear Information System (INIS)

    Gold, R.

    1977-01-01

    For more than 60 years, natural radiation has offered broad opportunities for basic research as evidenced by many fundamental discoveries. Within the last decade, however, dramatic changes have occurred in the motivation and direction of this research. The urgent need for economical energy sources entailing acceptably low levels of environmental impact has compelled the applied aspects of our radiation environment to become overriding considerations. It is within this general framework that state-of-the-art environmental dosimetry techniques are reviewed. Although applied motivation and relevance underscores the current milieu for both reactor and environmental dosimetry, a perhaps even more unifying force is the broad similarity of reactor and environmental radiation fields. In this review, a comparison of these two mixed radiation fields is presented stressing the underlying similarities that exist. On this basis, the evolution of a strong inner bond between dosimetry methods for both reactor and environmental radiation fields is described. The existence of this bond will be illustrated using representative examples of observed spectra. Dosimetry methods of particularly high applicability for both of these fields are described. Special emphasis is placed on techniques of high sensitivity and absolute accuracy which are capable of resolving the components of these mixed radiation fields

  9. Integral test of JENDL dosimetry file using fast neutron field in the Experimental Fast Reactor JOYO

    International Nuclear Information System (INIS)

    Aoyama, Takafumi; Sekine, Takashi

    1999-09-01

    In order to evaluate the applicability of the JENDL dosimetry file, an integral test using a fast neutron spectrum field in the Experimental Fast Reactor JOYO Mark-II core was performed. The dosimeter set consisting of eight reactions of 46 Ti(n,p) 46 Sc, 54 Fe(n,p) 54 Mn, 58 Fe(n,γ) 59 Fe, 58 Ni(n,p) 58 Co, 59 Co(n,γ) 60 Co, 63 Cu(n,α) 60 Co, 238 U fission and 237 Np fission was irradiated for approximately 30 days near the core center of the JOYO Mk-II. Neutron flux at the dosimeter position was calculated using the two dimensional discrete ordinate transport code 'DORT'. The core configuration was modeled in XY geometry, and the 100 group cross section set of JSD-J2 / JFT-J2, which was processed from JENDL-2, was utilized. The absolute value of neutron flux was normalized so that the 235 U fission rate using the calculated neutron spectrum agreed with the measured reaction rate. The 103 group cross section data were processed by 'NJOY' code for nuclides to be used in the JOYO dosimetry. As the results of integral test for JENDL/D-99 (new file) and JENDL/D-91 (previous file), calculated values by JENDL/D-99 agreed well with the experimental values, and the C/E ratios ranged from 0.95 to 1.22. By comparing the results between JENDL/D-99 and JENDL/D-91, small differences exist, except for 58 Fe(n, γ) 59 Fe reaction, which was improved significantly in JENDL/D-99. (author)

  10. Acquisition of biokinetic data for internal dose calculations for some novel radiopharmaceuticals

    International Nuclear Information System (INIS)

    Smith, T.; Zanelli, G.D.; Crawley, C.W.

    1986-01-01

    Estimation of radiation dose commitment, expresses as an effective dose equivalent, is a prior requisite to the application for a license to administer radiopharmaceuticals and, therefore, in the case of novel radiopharmaceuticals is leading to an increasing awareness of the need for dosimetry-orientated studies. In this laboratory potential new radiopharmaceuticals are investigated initially by animal studies to assess the possible distribution in man, and subsequently in controlled volunteer studies designed to obtain the maximum possible amount of biokinetic data to allow accurate estimation of radiation dose. A variety of techniques are used for this purpose, including profile counting, partial and whole-body scanning by LFOV gamma camera and whole-body counting, in addition to the analysis of radioactivity in blood and excreta. The use of these techniques is illustrated for the acquisition of biokinetic data and subsequent dosimetry of three novel radiopharmaceuticals: 77 Br-p-bromospiperone (quantification of dopamine receptors in the brain). 99 Tc/sup m/-porphyrins and 99 Tc/sup m/ DEPE (a possible novel blood pool marker for MUGA studies). 14 references, 14 figures, 2 tables

  11. Energy Metabolism and Human Dosimetry of Tritium

    International Nuclear Information System (INIS)

    Galeriu, D.; Takeda, H.; Melintescu, A.; Trivedi, A.

    2005-01-01

    In the frame of current revision of human dosimetry of 14 C and tritium, undertaken by the International Commission of Radiological Protection, we propose a novel approach based on energy metabolism and a simple biokinetic model for the dynamics of dietary intake (organic 14 C, tritiated water and Organically Bound Tritium-OBT). The model predicts increased doses for HTO and OBT comparing to ICRP recommendations, supporting recent findings

  12. Small radiation field dosimetry with 2-methylalanine miniature dosimeters at K-band electron paramagnetic resonance

    International Nuclear Information System (INIS)

    Chen, F.; Guzman Calcina, C.S.; Almeida, A. de; Almeida, C.E. de; Baffa, O.

    2007-01-01

    Minidosimeters of 2-methyalanine (2MA) with millimeter dimensions were produced and tested for small radiation field dosimetry. Their performance was assessed by measuring the relative output factor (ROF), beam profile (BP) and penumbra width values and were determined for square fields of 0.5x0.5, 1x1, 3x3, 5x5 and 10x10cm 2 . These results were compared with those obtained for Kodak X-Omat V radiographic film. The 2MA minidosimeters (mini2MA) were irradiated with 6 MV X-rays Varian/Clinac 2100 linear accelerator with SSD of 100 cm and depth of 1.5 cm (depth for build-up equilibrium). EPR measurements were made with a K-Band (24 GHz) spectrometer. The ROF and BP results demonstrate that the dimensions of the mini2MA are adequate for the field sizes used in this experiment. The results for penumbra width indicate that the spatial resolution of the mini2MA is comparable with that of radiographic film

  13. 100 years of solid state dosimetry and radiation protection dosimetry

    International Nuclear Information System (INIS)

    Bartlett, David T.

    2008-01-01

    The use of solid state detectors in radiation dosimetry has passed its 100th anniversary. The major applications of these detectors in radiation dosimetry have been in personal dosimetry, retrospective dosimetry, dating, medical dosimetry, the characterization of radiation fields, and also in microdosimetry and radiobiology research. In this introductory paper for the 15th International Conference, I shall speak of the history of solid state dosimetry and of the radiation measurement quantities that developed at the same time, mention some landmark developments in detectors and applications, speak a bit more about dosimetry and measurement quantities, and briefly look at the past and future

  14. Clinical dosimetry

    International Nuclear Information System (INIS)

    Rassow, J.

    1973-01-01

    The main point of this paper on clinical dosimetry which is to be understood here as application of physical dosimetry on accelerators in medical practice, is based on dosimetric methodics. Following an explanation of the dose parameters and description of the dose distribution important for clinical practice as well as geometric irradiation parameters, the significance of a series of physical parameters such as accelerator energy, surface energy of average stopping power etc. is dealt with in detail. Following a section on field homogenization with bremsstrahlung and electron radiation, details on dosimetry in clinical practice are given. Finally, a few problems of dosemeter or monitor calibration on accelerators are described. The explanations are supplemented by a series of diagrams and tables. (ORU/LH) [de

  15. Development, implementation and quality assurance of biokinetic models within CONRAD

    International Nuclear Information System (INIS)

    Nosske, D.; Birchall, A.; Blanchardon, E.; Breustedt, B.; Giussani, A.; Luciani, A.; Oeh, U.; Lopez, M. A.

    2008-01-01

    The work of the Task Group 5.2 'Research Studies on Biokinetic Models' of the CONRAD project is presented. New biokinetic models have been implemented by several European institutions. Quality assurance procedures included intercomparison of the results as well as quality assurance of model formulation. Additionally, the use of the models was examined leading to proposals of tuning parameters. Stable isotope studies were evaluated with respect to their implications to the new models, and new biokinetic models were proposed on the basis of their results. Furthermore, the development of a biokinetic model describing the effects of decorporation of actinides by diethylenetriaminepentaacetic acid treatment was initiated. (authors)

  16. Internal dosimetry, past and future

    International Nuclear Information System (INIS)

    Johnson, J.R.

    1989-03-01

    This paper is a review of the progress in the dosimetry of internally deposited radionuclides (internal dosimetry) since World War II. Previous to that, only naturally occurring radionuclides were available and only a limited number of studies of biokinetics and dosimetry were done. The main radionuclides studied were 226 Ra, 228 Ra, and 224 Ra but natural uranium was also studied mainly because of its toxic effect as a heavy metal, and not because it was radioactive. The effects of 226 Ra in bone, mainly from the radium dial painters, also formed the only bases for the radiotoxicity of radionuclides in bone for many years, and it is still, along with 224 Ra, the main source of information on the effects of alpha emitters in bone. The publications of the International Commission on Radiological Protection that have an impact on internal dosimetry are used as mileposts for this review. These series of publications, more than any other, represent a broad consensus of opinion within the radiation protection community at the time of their publication, and have formed the bases for radiation protection practice throughout the world. This review is not meant to be exhaustive; it is meant to be a personnel view of the evolution of internal dosimetry, and to present the author's opinion of what the future directions in internal dosimetry will be. 39 refs., 2 tabs

  17. SU-F-T-579: Extrapolation Techniques for Small Field Dosimetry Using Gafchromic EBT3 Film

    Energy Technology Data Exchange (ETDEWEB)

    Morales, J [Chris OBrien Lifehouse, Camperdown, NSW (Australia)

    2016-06-15

    Purpose: The purpose of this project is to test an experimental approach using an extrapolation technique for Gafchromic EBT3 film for small field x-ray dosimetry. Methods: Small fields from a Novalis Tx linear accelerator with HD Multileaf Collimators with 6 MV was used. The field sizes ranged from 5 × 5 to 50 × 50 mm2 MLC fields and a range of circular cones of 4 to 30 mm2 diameters. All measurements were performed in water at an SSD of 100 cm and at a depth of 10 cm. The relative output factors (ROFs) were determined from an extrapolation technique developed to eliminate the effects of partial volume averaging in film scan by scanning films with high resolution (1200 DPI). The size of the regions of interest (ROI) was varied to produce a plot of ROFs versus ROI which was then extrapolated to zero ROI to determine the relative output factor. The results were compared with other solid state detectors with proper correction, namely, IBA SFD diode, PTW 60008 and PTW 60012 diode. Results: For the 4 mm cone, the extrapolated ROF had a value of 0.658 ± 0.014 as compared to 0.642 and 0.636 for 0.5 mm and 1 mm2 ROI analysis, respectively. This showed a change in output factor of 2.4% and 3.3% at this comparative ROI sizes. In comparison, the 25 mm cone had a difference in measured output factor of 0.3% and 0.5% between 0.5 and 1.0 mm, respectively compared to zero volume. For the fields defined by MLCs a difference of up to 2% for 5×5 mm2 was observed. Conclusion: A measureable difference can be seen in ROF based on the ROI when radiochromic film is used. Using extrapolation technique from high resolution scanning a good agreement can be achieved.

  18. FNTD radiation dosimetry system enhanced with dual-color wide-field imaging

    International Nuclear Information System (INIS)

    Akselrod, M.S.; Fomenko, V.V.; Bartz, J.A.; Ding, F.

    2014-01-01

    At high neutron and photon doses Fluorescent Nuclear Track Detectors (FNTDs) require operation in analog mode and the measurement results depend on individual crystal color center concentration (coloration). We describe a new method for radiation dosimetry using FNTDs, which includes non-destructive, automatic sensitivity calibration for each individual FNTD. In the method presented, confocal laser scanning fluorescent imaging of FNTDs is combined with dual-color wide field imaging of the FNTD. The calibration is achieved by measuring the color center concentration in the detector through fluorescence imaging and reducing the effect of diffuse reflection on the lapped surface of the FNTD by imaging with infra-red (IR) light. The dual-color imaging of FNTDs is shown to provide a good estimation of the detector sensitivity at high doses of photons and neutrons, where conventional track counting is impeded by track overlap. - Highlights: • New method and optical imaging head was developed for FNTD used at high doses. • Dual-color wide-field imaging used for color center concentration measurement. • Green fluorescence corrected by diffuse reflection used for sensitivity correction. • FNTD dose measurements performed in analog processing mode

  19. The calibration method for personal dosimetry system in photon and neutron radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Trousil, J; Plichta, J [CSOD, Prague (Czech Republic); Nikodemova, D [SOD, Bratislava (Slovakia)

    1996-12-31

    The type testing of dosimetry system was performed with standard photon radiation fields within the energy range 15 keV to 1.25 MeV and electron radiation fields within the range 0.2 MeV to 3 MeV. For type testing of neutron dosimeters {sup 252}Cf and {sup 241}Am-Be radionuclide neutron sources was used, as well as a 14 MeV neutron generator. The neutron sources moderated by various moderating and absorbing materials was also used. The routine calibration of individual photon dosemeters was carried out using a {sup 137}Cs calibration source in the air kerma quality in the dose range 0.2 mGy to 6 Gy. The type testing of neutron dosemeters was performed in collaboration with Nueherberg laboratory on neutron generator with neutron energies -.57; 1.0;; 5.3 and 15.1 MeV. The fading and angular dependence testing was also included in the tests of both dosemeter systems. (J.K.).

  20. ESR-dosimetry in thermal and epithermal neutron fields for application in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Tobias

    2016-01-22

    Dosimetry is essential for every form of radiotherapy. In Boron Neutron Capture Therapy (BNCT) mixed neutron and gamma fields have to be considered. Dose is deposited in different neutron interactions with elements in the penetrated tissue and by gamma particles, which are always part of a neutron field. The therapeutic dose in BNCT is deposited by densely ionising particles, originating from the fragmentation of the isotope boron-10 after capture of a thermal neutron. Despite being investigated for decades, dosimetry in neutron beams or fields for BNCT remains complex, due to the variety in type and energy of the secondary particles. Today usually ionisation chambers combined with metal foils are used. The applied techniques require extensive effort and are time consuming, while the resulting uncertainties remain high. Consequently, the investigation of more effective techniques or alternative dosimeters is an important field of research. In this work the possibilities of ESR-dosimeters in those fields have been investigated. Certain materials, such as alanine, generate stable radicals upon irradiation. Using Electron Spin Resonance (ESR) spectrometry the amount of radicals, which is proportional to absorbed dose, can be quantified. Different ESR detector materials have been irradiated in the thermal neutron field of the research reactor TRIGA research reactor in Mainz, Germany, with five setups, generating different secondary particle spectra. Further irradiations have been conducted in two epithermal neutron beams. The detector response, however, strongly depends on the dose depositing particle type and energy. It is hence necessary to accompany measurements by computational modelling and simulation. In this work the Monte Carlo code FLUKA was used to calculate absorbed doses and dose components. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using amorphous track models. For the simulation, detailed models of

  1. SU-F-T-557: Evaluation of Detector Response in Rectangular Small Field Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, A [University of Toledo, Toledo, Ohio (United States); Tanny, S [SUNY Upstate Medical University, Syracuse NY (United States); Parsai, E; Sperling, N [University of Toledo Medical Center, Toledo, OH (United States)

    2016-06-15

    Purpose: As stereotactic treatment modalities grow towards becoming the standard of care, the need for accurate dose computation in small fields is becoming increasingly essential. The purpose of this study is to evaluate the response of different detectors, intended for small field dosimetry, in jaw defined small rectangular fields by analyzing output factors from a stereotactic clinical accelerator. Methods: Two Dosimeters, the Exradin A26 Microionization Chamber (Standard Imaging) and Edge Diode Detector (Sun Nuclear) were used to measure output factors taken on the Varian Edge Stereotactic Linear accelerator. Measurements were taken at 6MV and 6FFF at 10cm depth, 100cm SSD in a 48×48×40cm3 Welhoffer BluePhantom2 (IBA) with X and Y jaws set from 0.6 to 2.0cm. Output factors were normalized to a 5×5cm2 machine-specific reference field. Measurements were made in the vertical orientation for the A26 and horizontal orientation for both the A26 and Edge. Output factors were measured as: OF{sub FS} = M{sub FS}/M{sub ref} where M{sub FS} and M{sub ref} are the measured signals for the clinical field and the reference field, respectively. Measured output factors were then analyzed to establish relative responses of the detectors in small fields. Results: At 6MV the Edge detector exhibited a variation in output factors dependent on jaw positioning (X-by-Y vs Y-by-X) of 5.7% of the 5×5cm reference output and a variation of 3.33% at 6FFF. The A26 exhibited variation of output factor dependent on jaw positioning of upto 7.7% of the 5×5cm reference field at 6MV and upto 5.33% at 6FFF. Conclusion: Both the Edge detector and A26 responded as expected at small fields however a dependence on the jaw positioning was noted. At 6MV and 6FFF the detector response showed an increased dependence on the positioning of the X jaws as compared to the positioning of the Y jaws.

  2. A radiophotoluminescent glass plate system for medium-sized field dosimetry

    International Nuclear Information System (INIS)

    Nakagawa, Keiichi; Koyanagi, Hiroki; Shiraki, Takashi; Saegusa, Shigeki; Sasaki, Katsutake; Oritate, Takashi; Mima, Kazuo; Miyazawa, Masanori; Ishidoya, Tatsuyo; Ohtomo, Kuni; Yoda, Kiyoshi

    2005-01-01

    A two-dimensional radiophotoluminescent system for medium-sized field dosimetry has been developed using a silver-activated phosphate glass plate with a dimension of 120 mmx120 mmx1 mm and a readout unit comprising a UV excitation lamp and a CCD imager. A dose ranging from 0 to 400 cGy, provided by a 6 MV x-ray beam, was delivered to the glass plate oriented perpendicularly to the beam and positioned in a water phantom at a depth of 10 cm, where the center of the glass plate coincided with the linac isocenter. After the dose delivery, the glass plate was placed in the readout system. The CCD output intensity increased linearly with the applied dose. The angular dependence of response on the direction of radiation incidence was measured by rotating the glass plate in the water phantom, indicating that the output remained constant up to 75 deg. from perpendicular incident direction, followed by a steep reduction down to 85% at an angle of 90 deg. A lateral dose distribution resulting from a 60 mmx60 mm irradiation was compared between the glass plate and an x-ray film having had the same exposure, showing that the glass plate and the x-ray film led to identical dose distributions. The dose reproducibility for a glass plate and the sensitivity variation among different glass plates were also evaluated

  3. MAGAT gel dosimetry for its application in small field treatment techniques

    International Nuclear Information System (INIS)

    Gopishankar, N; Vivekanandhan, S; Kale, S S; Rath, G K; Kumaran, S Senthil; Thulkar, Sanjay; Subramani, V; Laviraj, M A; Bisht, R K; Mahapatra, A K

    2010-01-01

    Purpose of this work is to present the role of in-house manufactured MAGAT gel for treatment verification in small field dosimetric techniques such as Gammaknife (GK) and intensity-modulated radiation therapy (IMRT). Magnetic resonance imaging (MRI) is one of the most extensively used imaging technique for polymer gel dosimetry hence we used this method for gel evaluation. Different MR scanners and MRI sequences were used in this study for obtaining calibration plot between R2 and absorbed dose. An experimental plan was created for Gammaknife and IMRT. The prepared gel was filled in spherical glass phantom and in-house designed human head shape phantom for verification purpose. We used 8 TE values for all the imaging sequences for two reasons. Firstly it is sufficient enough to give good signal to noise ratio. Second considering the enormous scanning time involved in multiple spin echo sequence. MATLAB based in-house programs were used for R2 estimation and dose comparison. The isodose comparison with MAGAT gel showed reasonable agreement for both Gammaknife and IMRT techniques.

  4. K-band EPR dosimetry: small-field beam profile determination with miniature alanine dosimeter

    International Nuclear Information System (INIS)

    Chen, Felipe; Graeff, Carlos F.O.; Baffa, Oswaldo

    2005-01-01

    The use of small-size alanine dosimeters presents a challenge because the signal intensity is less than the spectrometer sensitivity. K-band (24 GHz) EPR spectrometer seems to be a good compromise between size and sensitivity of the sample. Miniature alanine pellets were evaluated for small-field radiation dosimetry. Dosimeters of DL-alanine/PVC with dimensions of 1.5 mm diameter and 2.5 mm length with 5 mg mass were developed. These dosimeters were irradiated with 10 MV X-rays in the dose range 0.05-60 Gy and the first harmonic (1 h) spectra were recorded. Microwave power, frequency and amplitude of modulation were optimized to obtain the best signal-to-noise ratio (S/N). For beam profile determination, a group of 25 dosimeters were placed in an acrylic device with dimensions of (7.5x2.5x1) cm 3 and irradiated with a (3x3) cm 2 10 MV X-rays beam field size. The dose at the central region of the beam was 20 Gy at a depth of 2.2 cm (build up for acrylic). The acrylic device was oriented perpendicular to the beam axis and to the gantry rotation axis. For the purposes of comparison of the spatial resolution, the beam profile was also determined with a radiographic film and 2 mm aperture optical densitometer; in this case the dose was 1 cGy. The results showed a similar spatial resolution for both types of dosimeters. The dispersion in dose reading was larger for alanine in comparison with the film, but alanine dosimeters can be read faster and more directly than film over a wide dose range

  5. Reactor dosimetry integral reaction rate data in LMFBR Benchmark and standard neutron fields: status, accuracy and implications

    International Nuclear Information System (INIS)

    Fabry, A.; Ceulemans, H.; Vandeplas, P.; McElroy, W.N.; Lippincott, E.P.

    1977-01-01

    This paper provides conclusions that may be drawn regarding the consistency and accuracy of dosimetry cross-section files on the basis of integral reaction rate data measured in U.S. and European benchmark and standard neutron fields. In a discussion of the major experimental facilities CFRMF (Idaho Falls), BIGTEN (Los Alamos), ΣΣ (Mol, Bucharest), NISUS (London), TAPIRO (Roma), FISSION SPECTRA (NBS, Mol, PTB), attention is paid to quantifying the sensitivity of computed integral data relative to the presently evaluated accuracy of the various neutron spectral distributions. The status of available integral data is reviewed and the assigned uncertainties are appraised, including experience gained by interlaboratory comparisons. For all reactions studied and for the various neutron fields, the measured integral data are compared to the ones computed from the ENDF/B-IV and the SAND-II dosimetry cross-section libraries as well as to some other differential data in relevant cases. This comparison, together with the proposed sensitivity and accuracy assessments, is used, whenever possible, to establish how well the best cross-sections evaluated on the basis of differential measurements (category I dosimetry reactions) are reliable in terms of integral reaction rates prediction and, for those reactions for which discrepancies are indicated, in which energy range it is presumed that additional differential measurements might help. For the other reactions (category II), the inconsistencies and trends are examined. The need for further integral measurements and interlaboratory comparisons is also considered

  6. Monte Carlo and experimental determination of correction factors for gamma knife perfexion small field dosimetry measurements

    Science.gov (United States)

    Zoros, E.; Moutsatsos, A.; Pappas, E. P.; Georgiou, E.; Kollias, G.; Karaiskos, P.; Pantelis, E.

    2017-09-01

    Detector-, field size- and machine-specific correction factors are required for precise dosimetry measurements in small and non-standard photon fields. In this work, Monte Carlo (MC) simulation techniques were used to calculate the k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} and k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors for a series of ionization chambers, a synthetic microDiamond and diode dosimeters, used for reference and/or output factor (OF) measurements in the Gamma Knife Perfexion photon fields. Calculations were performed for the solid water (SW) and ABS plastic phantoms, as well as for a water phantom of the same geometry. MC calculations for the k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors in SW were compared against corresponding experimental results for a subset of ionization chambers and diode detectors. Reference experimental OF data were obtained through the weighted average of corresponding measurements using TLDs, EBT-2 films and alanine pellets. k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} values close to unity (within 1%) were calculated for most of ionization chambers in water. Greater corrections of up to 6.0% were observed for chambers with relatively large air-cavity dimensions and steel central electrode. A phantom correction of 1.006 and 1.024 (breaking down to 1.014 from the ABS sphere and 1.010 from the accompanying ABS phantom adapter) were calculated for the SW and ABS phantoms, respectively, adding up to k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} corrections in water. Both measurements and MC calculations for the diode and microDiamond detectors resulted in lower than unit k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors, due to their denser sensitive volume and encapsulation materials. In comparison, higher than unit k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} results for the ionization chambers suggested field size depended dose underestimations (being significant for the 4 mm field), with magnitude depending on the combination of

  7. Dosimetry measurements using Timepix in mixed radiation fields induced by heavy ions; comparison with standard dosimetry methods

    Czech Academy of Sciences Publication Activity Database

    Ploc, Ondřej; Kubančák, Ján; Sihver, L.; Uchihori, Y.; Jakoubek, J.; Ambrožová, Iva; Molokanov, A. G.; Pinsky, L.

    2014-01-01

    Roč. 55, S1 (2014), i141-i142 ISSN 0449-3060 R&D Projects: GA MŠk(CZ) LG13031; GA MŠk LG14004 Institutional support: RVO:61389005 Keywords : LET spectrometry * heavy ions * mixed radiation field * pixel detector Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.797, year: 2014

  8. Toward acquiring comprehensive radiosurgery field commissioning data using the PRESAGE/optical-CT 3D dosimetry system

    Energy Technology Data Exchange (ETDEWEB)

    Clift, Corey; Thomas, Andrew; Chang Zheng; Oldham, Mark [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States); Adamovics, John [Department of Chemistry, Rider University, Lawrenceville, NJ 08648 (United States); Das, Indra [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202 (United States)], E-mail: cclift@montefiore.org

    2010-03-07

    Achieving accurate small field dosimetry is challenging. This study investigates the utility of a radiochromic plastic PRESAGE read with optical-CT for the acquisition of radiosurgery field commissioning data from a Novalis Tx system with a high-definition multileaf collimator (HDMLC). Total scatter factors (S{sub c,p}), beam profiles, and penumbrae were measured for five different radiosurgery fields (5, 10, 20, 30 and 40 mm) using a commercially available optical-CT scanner (OCTOPUS, MGS Research). The percent depth dose (PDD), beam profile and penumbra of the 10 mm field were also measured using a higher resolution in-house prototype CCD-based scanner. Gafchromic EBT film was used for independent verification. Measurements of S{sub c,p} made with PRESAGE and film agreed with mini-ion chamber commissioning data to within 4% for every field (range 0.2-3.6% for PRESAGE, and 1.6-3.6% for EBT). PDD, beam profile and penumbra measurements made with the two PRESAGE/optical-CT systems and film showed good agreement with the high-resolution diode commissioning measurements with a competitive resolution (0.5 mm pixels). The in-house prototype optical-CT scanner allowed much finer resolution compared with previous applications of PRESAGE. The advantages of the PRESAGE (registered) system for small field dosimetry include 3D measurements, negligible volume averaging, directional insensitivity, an absence of beam perturbations, energy and dose rate independence.

  9. Toward acquiring comprehensive radiosurgery field commissioning data using the PRESAGE/optical-CT 3D dosimetry system

    International Nuclear Information System (INIS)

    Clift, Corey; Thomas, Andrew; Chang Zheng; Oldham, Mark; Adamovics, John; Das, Indra

    2010-01-01

    Achieving accurate small field dosimetry is challenging. This study investigates the utility of a radiochromic plastic PRESAGE read with optical-CT for the acquisition of radiosurgery field commissioning data from a Novalis Tx system with a high-definition multileaf collimator (HDMLC). Total scatter factors (S c,p ), beam profiles, and penumbrae were measured for five different radiosurgery fields (5, 10, 20, 30 and 40 mm) using a commercially available optical-CT scanner (OCTOPUS, MGS Research). The percent depth dose (PDD), beam profile and penumbra of the 10 mm field were also measured using a higher resolution in-house prototype CCD-based scanner. Gafchromic EBT film was used for independent verification. Measurements of S c,p made with PRESAGE and film agreed with mini-ion chamber commissioning data to within 4% for every field (range 0.2-3.6% for PRESAGE, and 1.6-3.6% for EBT). PDD, beam profile and penumbra measurements made with the two PRESAGE/optical-CT systems and film showed good agreement with the high-resolution diode commissioning measurements with a competitive resolution (0.5 mm pixels). The in-house prototype optical-CT scanner allowed much finer resolution compared with previous applications of PRESAGE. The advantages of the PRESAGE (registered) system for small field dosimetry include 3D measurements, negligible volume averaging, directional insensitivity, an absence of beam perturbations, energy and dose rate independence.

  10. Toward acquiring comprehensive radiosurgery field commissioning data using the PRESAGE®/ optical-CT 3D dosimetry system

    Science.gov (United States)

    Clift, Corey; Thomas, Andrew; Adamovics, John; Chang, Zheng; Das, Indra; Oldham, Mark

    2010-03-01

    Achieving accurate small field dosimetry is challenging. This study investigates the utility of a radiochromic plastic PRESAGE® read with optical-CT for the acquisition of radiosurgery field commissioning data from a Novalis Tx system with a high-definition multileaf collimator (HDMLC). Total scatter factors (Sc, p), beam profiles, and penumbrae were measured for five different radiosurgery fields (5, 10, 20, 30 and 40 mm) using a commercially available optical-CT scanner (OCTOPUS, MGS Research). The percent depth dose (PDD), beam profile and penumbra of the 10 mm field were also measured using a higher resolution in-house prototype CCD-based scanner. Gafchromic EBT® film was used for independent verification. Measurements of Sc, p made with PRESAGE® and film agreed with mini-ion chamber commissioning data to within 4% for every field (range 0.2-3.6% for PRESAGE®, and 1.6-3.6% for EBT). PDD, beam profile and penumbra measurements made with the two PRESAGE®/optical-CT systems and film showed good agreement with the high-resolution diode commissioning measurements with a competitive resolution (0.5 mm pixels). The in-house prototype optical-CT scanner allowed much finer resolution compared with previous applications of PRESAGE®. The advantages of the PRESAGE® system for small field dosimetry include 3D measurements, negligible volume averaging, directional insensitivity, an absence of beam perturbations, energy and dose rate independence.

  11. A biokinetic model of inhaled Cm compounds in dogs: Application to human exposure data

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Mewhinney, J.A.

    1989-01-01

    Curium isotopes are major by-products in irradiated nuclear reactor fuel and comprise a significant fraction of the alpha-emitting radionuclide inventory. Although little use is currently being made of purified Cm sources, such usage is possible if reprocessing of spent fuel becomes feasible. Because little information is available on the biokinetics and dosimetry of inhaled Cm compounds, a study was conducted in which adult beagle dogs received a single inhalation exposure to either a monodisperse aerosol of 244Cm2O3 (1.4 micron activity median aerodynamic diameter [AMAD]; sigma g = 1.16) or a polydisperse aerosol of 244Cm (NO3)3 (1.1 micron AMAD; sigma g = 1.74). At times ranging from 4 h to 2 y after exposure, animals were sacrificed and their tissues analyzed for Cm content. The data describing the uptake and retention of 244Cm in the different organs and tissues and the measured rates of excretion of these dogs formed the basis on which a biokinetic model of Cm metabolism was constructed. This Cm model was based on a previously published model of the biokinetics of 241Am that was shown to be applicable to data from human cases of inhalation exposure to 241Am aerosols. This Cm model was found to be adequate to describe the biological distribution of Cm in dogs and was also applied to the sparse data from humans. Reasonable agreement was found between the model predictions for lung retention of Cm and for urinary excretion patterns in humans

  12. Small field dose delivery evaluations using cone beam optical computed tomography-based polymer gel dosimetry

    Directory of Open Access Journals (Sweden)

    Timothy Olding

    2011-01-01

    Full Text Available This paper explores the combination of cone beam optical computed tomography with an N-isopropylacrylamide (NIPAM-based polymer gel dosimeter for three-dimensional dose imaging of small field deliveries. Initial investigations indicate that cone beam optical imaging of polymer gels is complicated by scattered stray light perturbation. This can lead to significant dosimetry failures in comparison to dose readout by magnetic resonance imaging (MRI. For example, only 60% of the voxels from an optical CT dose readout of a 1 l dosimeter passed a two-dimensional Low′s gamma test (at a 3%, 3 mm criteria, relative to a treatment plan for a well-characterized pencil beam delivery. When the same dosimeter was probed by MRI, a 93% pass rate was observed. The optical dose measurement was improved after modifications to the dosimeter preparation, matching its performance with the imaging capabilities of the scanner. With the new dosimeter preparation, 99.7% of the optical CT voxels passed a Low′s gamma test at the 3%, 3 mm criteria and 92.7% at a 2%, 2 mm criteria. The fitted interjar dose responses of a small sample set of modified dosimeters prepared (a from the same gel batch and (b from different gel batches prepared on the same day were found to be in agreement to within 3.6% and 3.8%, respectively, over the full dose range. Without drawing any statistical conclusions, this experiment gives a preliminary indication that intrabatch or interbatch NIPAM dosimeters prepared on the same day should be suitable for dose sensitivity calibration.

  13. Comparative measurements on different thermoluminescence materials for the dosimetry in mixed radiation fields; Vergleichende Messungen an unterschiedlichen Thermolumineszenzmaterialien fuer die Dosimetrie in gemischten Strahlenfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Pillath, J.; Uray, I.

    2006-05-15

    LiF-based thermoluminescence materials (TL materials) have proved efficient and become established for dosimetry for many years now. In combination with suitable filtrations or moderators, they permit high-precision measurements of the radiation doses of all types of radiation relevant in radiation protection. The development of highly sensitive LiF materials with a doping of Mg, P and Cu has made it possible to measure doses down to one {mu}Sv. The measurements presented here specifically serve to phenomenologically analyse the glow curve structure of normally and highly sensitive LiF-TL materials in mixed gamma-neutron radiation fields. The sensitivity of the different TL materials to different types of radiation and the influence of the radiation types and of the evaluation parameters on the structure of the glow curves is examined. It is made apparent how information about the composition and doses of the individual components of a radiation field can be obtained by decomposing the glow curve into its individual peaks. (orig.)

  14. Establishing personal dosimetry procedure using optically stimulated luminescence dosimeters in photon and mixed photon-neutron radiation fields

    International Nuclear Information System (INIS)

    Le Ngoc Thiem; Bui Duc Ky; Trinh Van Giap; Nguyen Huu Quyet; Ho Quang Tuan; Vu Manh Khoi; Chu Vu Long

    2017-01-01

    According to Vietnamese Law on Atomic Energy, personal dosimetry (PD) for radiation workers is required periodically in order to fulfil the national legal requirements on occupational radiation dose management. Since the radiation applications have become popular in Vietnamese society, the thermal luminescence dosimeters (TLDs) have been used as passive dosimeters for occupational monitoring in the nation. Together with the quick increase in radiation applications and the number of personnel working in radiation fields, the Optically Stimulated Luminescence Dosimeters (OSLDs) have been first introduced since 2015. This work presents the establishment of PD measuring procedure using OSLDs which are used for measuring photons and betas known as Inlight model 2 OSL (OSLDs-p,e) and for measuring mixed radiations of neutrons, photons and betas known as Inlight LDR model 2 (OSLDs-n,p,e). Such following features of OSLDs are investigated: detection limit, energy response, linearity, reproducibility, angular dependency and fading with both types of OSLDs-p,e and OSLDs-n,p,e. The result of an intercomparison in PD using OSLDs is also presented in the work. The research work also indicates that OSL dosimetry can be an alternative method applied in PD and possibly become one of the most popular personal dosimetry method in the future. (author)

  15. Poster – 13: Evaluation of an in-house CCD camera film dosimetry imaging system for small field deliveries

    International Nuclear Information System (INIS)

    Lalonde, Michel; Alexander, Kevin; Olding, Tim; Schreiner, L. John; Kerr, Andrew T.

    2016-01-01

    Purpose: Radiochromic film dosimetry is a standard technique used in clinics to verify modern conformal radiation therapy delivery, and sometimes in research to validate other dosimeters. We are using film as a standard for comparison as we improve high-resolution three-dimensional gel systems for small field dosimetry; however, precise film dosimetry can be technically challenging. We report here measurements for fractionated stereotactic radiation therapy (FSRT) delivered using volumetric modulated arc therapy (VMAT) to investigate the accuracy and reproducibility of film measurements with a novel in-house readout system. We show that radiochromic film can accurately and reproducibly validate FSRT deliveries and also benchmark our gel dosimetry work. Methods: VMAT FSRT plans for metastases alone (PTV MET ) and whole brain plus metastases (WB+PTV MET ) were delivered onto a multi-configurational phantom with a sheet of EBT3 Gafchromic film inserted mid-plane. A dose of 400 cGy was prescribed to 4 small PTV MET structures in the phantom, while a WB structure was prescribed a dose of 200 cGy in the WB+PTV MET iterations. Doses generated from film readout with our in-house system were compared to treatment planned doses. Each delivery was repeated multiple times to assess reproducibility. Results and Conclusions: The reproducibility of film optical density readout was excellent throughout all experiments. Doses measured from the film agreed well with plans for the WB+PTV MET delivery. But, film doses for PTV MET only deliveries were significantly below planned doses. This discrepancy is due to stray/scattered light perturbations in our system during readout. Corrections schemes will be presented.

  16. Poster – 13: Evaluation of an in-house CCD camera film dosimetry imaging system for small field deliveries

    Energy Technology Data Exchange (ETDEWEB)

    Lalonde, Michel; Alexander, Kevin; Olding, Tim; Schreiner, L. John; Kerr, Andrew T. [Cancer Centre of Southeastern Ontario at KGH, Queen’s University (Canada)

    2016-08-15

    Purpose: Radiochromic film dosimetry is a standard technique used in clinics to verify modern conformal radiation therapy delivery, and sometimes in research to validate other dosimeters. We are using film as a standard for comparison as we improve high-resolution three-dimensional gel systems for small field dosimetry; however, precise film dosimetry can be technically challenging. We report here measurements for fractionated stereotactic radiation therapy (FSRT) delivered using volumetric modulated arc therapy (VMAT) to investigate the accuracy and reproducibility of film measurements with a novel in-house readout system. We show that radiochromic film can accurately and reproducibly validate FSRT deliveries and also benchmark our gel dosimetry work. Methods: VMAT FSRT plans for metastases alone (PTV{sub MET}) and whole brain plus metastases (WB+PTV{sub MET}) were delivered onto a multi-configurational phantom with a sheet of EBT3 Gafchromic film inserted mid-plane. A dose of 400 cGy was prescribed to 4 small PTV{sub MET} structures in the phantom, while a WB structure was prescribed a dose of 200 cGy in the WB+PTV{sub MET} iterations. Doses generated from film readout with our in-house system were compared to treatment planned doses. Each delivery was repeated multiple times to assess reproducibility. Results and Conclusions: The reproducibility of film optical density readout was excellent throughout all experiments. Doses measured from the film agreed well with plans for the WB+PTV{sub MET} delivery. But, film doses for PTV{sub MET} only deliveries were significantly below planned doses. This discrepancy is due to stray/scattered light perturbations in our system during readout. Corrections schemes will be presented.

  17. Relevance of the ICRP biokinetic model for dietary organically bound tritium

    International Nuclear Information System (INIS)

    Trivedi, A.

    1999-10-01

    Ingested dietary tritium can participate in metabolic processes, and become synthesized into organically bound tritium in the tissues and organs. The distribution and retention of the organically bound tritium throughout the body are much different than tritium in the body water. The International Commission on Radiological Protection (ICRP) Publication 56 (1989) has a biokinetic model to calculate dose from the ingestion of organically bound dietary tritium. The model predicts that the dose from the ingestion of organically bound dietary tritium is about 2.3 times higher than from the ingestion of the same activity of tritiated water. Under steady-state conditions, the calculated dose rate (using the first principle approach) from the ingestion of dietary organically bound tritium can be twice that from the ingestion of tritiated water. For an adult, the upper-bound dose estimate for the ingestion of dietary organically bound tritium is estimated to be close to 2.3 times higher than that of tritiated water. Therefore, given the uncertainty in the dose calculation with respect to the actual relevant dose, the ICRP biokinetic model for organically bound tritium is sufficient for dosimetry for adults. (author)

  18. Dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Musilek, L.; Seda, J.; Trousil, J.

    1992-01-01

    The publication deals with a major field of ionizing radiation dosimetry, viz., integrating dosimetric methods, which are the basic means of operative dose determination. It is divided into the following sections: physical and chemical effects of ionizing radiation; integrating dosimetric methods for low radiation doses (film dosimetry, nuclear emulsions, thermoluminescence, radiophotoluminescence, solid-state track detectors, integrating ionization dosemeters); dosimetry of high ionizing radiation doses (chemical dosimetric methods, dosemeters based on the coloring effect, activation detectors); additional methods applicable to integrating dosimetry (exoelectron emission, electron spin resonance, lyoluminescence, etc.); and calibration techniques for dosimetric instrumentation. (Z.S.). 422 refs

  19. Secondary standard dosimetry laboratory (SSDL)

    International Nuclear Information System (INIS)

    Md Saion bin Salikin.

    1983-01-01

    A secondary Standard Dosimetry Laboratory has been established in the Tun Ismail Research Centre, Malaysia as a national laboratory for reference and standardization purposes in the field of radiation dosimetry. This article gives brief accounts on the general information, development of the facility, programmes to be carried out as well as other information on the relevant aspects of the secondary standard dosimetry laboratory. (author)

  20. A new metallic oxide semiconductor field effect transistor detector for use of in vivo dosimetry

    International Nuclear Information System (INIS)

    Qi Zhenyu; Deng Xiaowu; Huang Shaomin; Kang Dehua; Anatoly Rosenfeld

    2006-01-01

    Objective: To investigate the application of a recently developed metallic oxide semiconductor field effect transistor (MOSFET) detector for use in vivo dosimetry. Methods: The MOSFET detector was calibrated for X-ray beams of 8 MV and 15 MV, as well as electron beams with energy of 6,8,12 and 18 MeV. The dose linearity of the MOSFET detector was investigated for the doses ranging from 0 up to 50 Gy using 8 MV X-ray beams. Angular effect was evaluated as well in a cylindrical PMMA phantom by changing the beam entrance angle every 15 degree clockwise. The MOSFET detector was then used for a breast cancer patient in vivo dose measurement, after the treatment plan was verified in a water phantom using a NE-2571 ion chamber, in vivo measurements were performed in the first and last treatment, and once per week during the whole treatment. The measured doses were then compared with planning dose to evaluate the accuracy of each treatment. Results: The MOSFET detector represented a good energy response for X-ray beams of 8 MV and 15 MV, and for electron beams with energy of 6 MeV up to 18 MeV. With the 6 V bias, Dose linearity error of the MOSFET detector was within 3.0% up to approximately 50 Gy, which can be significantly reduced to 1% when the detector was calibrated before and after each measurement. The MOSFET response varied within 1.5% for angles from 270 degree to 90 degree. However, maximum error of 10.0% was recorded comparing MOSFET response between forward and backward direction. In vivo measurement for a breast cancer patient using 3DCRT showed that, the average dose deviation between measurement and calculation was 2.8%, and the maximum error was less then 5.0%. Conclusions: The new MOSFET detector, with its advantages of being in size, easy use, good energy response and dose linearity, can be used for in vivo dose measurement. (authors)

  1. Comparative biokinetics of radiogallium and radioindium in mice

    International Nuclear Information System (INIS)

    Tsui, B.M.W.; Lathrop, K.A.

    1978-01-01

    The biokinetics of radiogallium and radioindium in normal mice are compared using the compartmental modelling analysis. The rate constants obtained provide useful information in understanding the physiological and biochemical kinetics of radionuclides in the intact object. A comparison of the compartmental models for gallium and indium reveals the similarities and differences between the biokinetics of the two radionuclides. Furthermore, the results provide valuable information and guidance for human studies and clinical use

  2. A biokinetic model for zinc for use in radiation protection

    International Nuclear Information System (INIS)

    Leggett, R.W.

    2012-01-01

    The physiology of the essential trace element zinc has been studied extensively in human subjects using kinetic analysis of time-dependent measurements of administered zinc tracers. A number of biokinetic models describing zinc exchange between plasma and tissues and endogenous excretion of zinc have been derived as fits to data for specific study groups. More rudimentary biokinetic models for zinc have been developed to estimate radiation doses from internally deposited radioisotopes of zinc. The latter models are designed to provide broadly accurate estimates of cumulative decays of zinc radioisotopes in tissues and are not intended as realistic descriptions of the directions of movement of zinc in the body. This paper reviews biokinetic data for zinc and proposes a physiologically meaningful biokinetic model for systemic zinc for use in radiation protection. The proposed model bears some resemblance to zinc models developed in physiological studies but depicts a finer division of systemic zinc and is based on a broader spectrum of data than previous models. The proposed model and the model for zinc currently recommended by the International Commission on Radiological Protection yield reasonably similar estimates of total-body retention and effective dose for internally deposited radioisotopes of zinc but much different systemic distributions of activity and much different dose estimates for some individual tissues, particularly the liver. - Highlights: ► Zinc is an essential trace element with numerous functions in the human body. ► Several biokinetic models for zinc have been developed from tracer studies on humans. ► More rudimentary biokinetic models for zinc have been developed in radiation protection. ► Biokinetic data for zinc are reviewed and a new biokinetic model is proposed for radiation protection. ► The proposed model may also be useful for investigation of zinc physiology and homeostasis.

  3. Electron spin resonance (ESR) spectroscopy applied to radiation dosimetry and other fields

    International Nuclear Information System (INIS)

    Schneider, C.C.J.

    1994-12-01

    A short introduction to the theory and practice of ESR spectroscopy is given. ESR alanine dosimetry for low and high LET (linear energy transfer) ionising radiation is described, indicating its advantages over traditional methods. Problems arising in the therapy dose range (below 5 Gy), and possible future developments, are mentioned. The application of ESR to the radiation processing of materials and foodstuffs, to geological dating, biology, molecular chemistry and to medicine is discussed. Some examples of chemical analyses are also presented. (orig.)

  4. Biokinetics and dosimetry of a hybrid formulation of {sup 9{sup m}}Tc-BN and {sup 99m}Tc-RGD{sub 2} starting from optic images in a murine model; Biocinetica y dosimetria de una formulacion hibrida de {sup 99m}Tc-BN y {sup 99m}Tc-RGD{sub 2} a partir de imagenes opticas en un modelo murino

    Energy Technology Data Exchange (ETDEWEB)

    Cornejo A, L. G.

    2015-07-01

    This work has the purpose of evaluate the biokinetics and absorbed dose of radiation of hybrid formulation {sup 99m}Tc-BN /{sup 99m}Tc-RGD{sub 2} in a murine model by optical imaging techniques using the multimodal preclinical in vivo image system Xtreme. The used method were the {sup 99m}Tc-BN, {sup 99m}Tc-RGD{sub 2} and {sup 99m}Tc-BN/{sup 99m}Tc-RGD{sub 2} formulas, with specific recognition for GRPr and the integrin s α(v)β(3) and α(v)β(5) respectively, was injected in the vein tail of three nude mousses with induce breast cancer tumors (cell line T-47-D), by the preclinical multimodal imaging system Xtreme (Bruker), optical images in different times was acquired (5, 10, 20 min, 2 and 24 h), using Images Processing Toolbox of MATLAB these images was transform from RGB format to gray scales and sectioned in five independent images corresponding to heart, kidneys, bladder and tumor areas. The intensity of each images was computed in counts per pixel, then those intensities was corrected for background, attenuation and scattering, using different factors for each phenomena previously calculated. Finally the activity values quantified vs time was fitted into a biokinetic model to obtain the disintegrations number and cumulate activities in each organ. With these data the radiation absorbed dose were calculated using MIRD methodology. Results: The number of disintegration and absorbed dose calculated in MBq h/MBq and mGy/MBq, of injected mouse with the {sup 99m}Tc-BN/{sup 99m}Tc-RGD{sub 2} formulation, was: 0.035 ± 0.65 E-02, 0.25 x 10{sub -5} ± 0.46 E-07; 0.393 ± 0.51 E-1, 2.85 E-05 ± 3.7 E-06; 0.306 ± 0.21 E-01, 2.11 E-05 ± 1.45 E-06 and 0.151 ± 0.19 E-01, 1.09 E-05 ± 1.42 E-06 , in heart, kidneys, bladder and tumor, respectively. The number of disintegration obtained in kidneys is comparable to those reported for Trinidad B. 2014 Conclusions: Our results demonstrated that using optical images and a code for image analyses development in MATLAB, could

  5. Laboratory-scale in situ bioremediation in heterogeneous porous media: biokinetics-limited scenario.

    Science.gov (United States)

    Song, Xin; Hong, Eunyoung; Seagren, Eric A

    2014-03-01

    Subsurface heterogeneities influence interfacial mass-transfer processes and affect the application of in situ bioremediation by impacting the availability of substrates to the microorganisms. However, for difficult-to-degrade compounds, and/or cases with inhibitory biodegradation conditions, slow biokinetics may also limit the overall bioremediation rate, or be as limiting as mass-transfer processes. In this work, a quantitative framework based on a set of dimensionless coefficients was used to capture the effects of the competing interfacial and biokinetic processes and define the overall rate-limiting process. An integrated numerical modeling and experimental approach was used to evaluate application of the quantitative framework for a scenario in which slow-biokinetics limited the overall bioremediation rate of a polycyclic aromatic hydrocarbon (naphthalene). Numerical modeling was conducted to simulate the groundwater flow and naphthalene transport and verify the system parameters, which were used in the quantitative framework application. The experiments examined the movement and biodegradation of naphthalene in a saturated, heterogeneous intermediate-scale flow cell with two layers of contrasting hydraulic conductivities. These experiments were conducted in two phases: Phase I, simulating an inhibited slow biodegradation; and Phase II, simulating an engineered bioremediation, with system perturbations selected to enhance the slow biodegradation rate. In Phase II, two engineered perturbations to the system were selected to examine their ability to enhance in situ biodegradation. In the first perturbation, nitrogen and phosphorus in excess of the required stoichiometric amounts were spiked into the influent solution to mimic a common remedial action taken in the field. The results showed that this perturbation had a moderate positive impact, consistent with slow biokinetics being the overall rate-limiting process. However, the second perturbation, which was to

  6. Characterization of a synthetic single crystal diamond detector for dosimetry in spatially fractionated synchrotron x-ray fields

    Energy Technology Data Exchange (ETDEWEB)

    Livingstone, Jayde, E-mail: Jayde.Livingstone@synchrotron.org.au; Häusermann, Daniel [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168 (Australia); Stevenson, Andrew W. [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and CSIRO Manufacturing, Clayton South, Victoria 3169 (Australia); Butler, Duncan J. [Australian Radiation Protection and Nuclear Safety Agency, Yallambie, Victoria 3085 (Australia); Adam, Jean-François [Equipe d’accueil Rayonnement Synchrotron et Recherche Médicale, Université Grenoble Alpes, European Synchrotron Radiation Facility - ID17, Grenoble 38043, France and Centre Hospitalier Universitaire de Grenoble, Grenoble 38043 (France)

    2016-07-15

    Purpose: Modern radiotherapy modalities often use small or nonstandard fields to ensure highly localized and precise dose delivery, challenging conventional clinical dosimetry protocols. The emergence of preclinical spatially fractionated synchrotron radiotherapies with high dose-rate, sub-millimetric parallel kilovoltage x-ray beams, has pushed clinical dosimetry to its limit. A commercially available synthetic single crystal diamond detector designed for small field dosimetry has been characterized to assess its potential as a dosimeter for synchrotron microbeam and minibeam radiotherapy. Methods: Experiments were carried out using a synthetic diamond detector on the imaging and medical beamline (IMBL) at the Australian Synchrotron. The energy dependence of the detector was characterized by cross-referencing with a calibrated ionization chamber in monoenergetic beams in the energy range 30–120 keV. The dose-rate dependence was measured in the range 1–700 Gy/s. Dosimetric quantities were measured in filtered white beams, with a weighted mean energy of 95 keV, in broadbeam and spatially fractionated geometries, and compared to reference dosimeters. Results: The detector exhibits an energy dependence; however, beam quality correction factors (k{sub Q}) have been measured for energies in the range 30–120 keV. The k{sub Q} factor for the weighted mean energy of the IMBL radiotherapy spectrum, 95 keV, is 1.05 ± 0.09. The detector response is independent of dose-rate in the range 1–700 Gy/s. The percentage depth dose curves measured by the diamond detector were compared to ionization chambers and agreed to within 2%. Profile measurements of microbeam and minibeam arrays were performed. The beams are well resolved and the full width at halfmaximum agrees with the nominal width of the beams. The peak to valley dose ratio (PVDR) calculated from the profiles at various depths in water agrees within experimental error with PVDR calculations from Gafchromic film data

  7. Comparison of Flattening Filter (FF) and Flattening-Filter-Free (FFF) 6 MV photon beam characteristics for small field dosimetry using EGSnrc Monte Carlo code

    Science.gov (United States)

    Sangeetha, S.; Sureka, C. S.

    2017-06-01

    The present study is focused to compare the characteristics of Varian Clinac 600 C/D flattened and unflattened 6 MV photon beams for small field dosimetry using EGSnrc Monte Carlo Simulation since the small field dosimetry is considered to be the most crucial and provoking task in the field of radiation dosimetry. A 6 MV photon beam of a Varian Clinac 600 C/D medical linear accelerator operates with Flattening Filter (FF) and Flattening-Filter-Free (FFF) mode for small field dosimetry were performed using EGSnrc Monte Carlo user codes (BEAMnrc and DOSXYZnrc) in order to calculate the beam characteristics using Educated-trial and error method. These includes: Percentage depth dose, lateral beam profile, dose rate delivery, photon energy spectra, photon beam uniformity, out-of-field dose, surface dose, penumbral dose and output factor for small field dosimetry (0.5×0.5 cm2 to 4×4 cm2) and are compared with magna-field sizes (5×5 cm2 to 40×40 cm2) at various depths. The results obtained showed that the optimized beam energy and Full-width-half maximum value for small field dosimetry and magna-field dosimetry was found to be 5.7 MeV and 0.13 cm for both FF and FFF beams. The depth of dose maxima for small field size deviates minimally for both FF and FFF beams similar to magna-fields. The depths greater than dmax depicts a steeper dose fall off in the exponential region for FFF beams comparing FF beams where its deviations gets increased with the increase in field size. The shape of the lateral beam profiles of FF and FFF beams varies remains similar for the small field sizes less than 4×4 cm2 whereas it varies in the case of magna-fields. Dose rate delivery for FFF beams shows an eminent increase with a two-fold factor for both small field dosimetry and magna-field sizes. The surface dose measurements of FFF beams for small field size were found to be higher whereas it gets lower for magna-fields than FF beam. The amount of out-of-field dose reduction gets

  8. SU-E-T-813: What Is the “real” Field-Size in Photon Dosimetry?

    Energy Technology Data Exchange (ETDEWEB)

    Gainey, M; Kollefrath, M; Saum, R; Bruggmoser, G [University Medical Centre Freiburg, Freiburg Im Breisgau, Baden-Wuerttemberg (Germany)

    2015-06-15

    Purpose: The definition of field sizes in photon dosimetry and the measurement of profiles are non-trivial. Current definitions are nominal, geometric, dosimetric (actual) or equivalent field size. In reality most detectors are not water equivalent since they contain air or high density materials. These materials can blur profiles, particularly in small fields. If necessary, detector and field size-specific volume dependent effects need to be considered. Methods: A TrueBeam-linac (Varian Medical Systems) was used. All measurements were performed within a water phantom (MP3, PTW-Freiburg), with filter (WFF) and without filter (FFF), using ionization chambers, shielded and unshielded diodes and diamond detectors. The position of the jaws was verified according to our QA-system. Field size profiles were taken at a defined depth (SSD =90 cm, SCD=100 cm). The penumbra of the profiles measured with the various detectors was compared to determine the dosimetric field size. For the evaluation of the field sizes the inclination points were also calculated. Results: The field size, both for the WFF and the FFF-mode, coincided within 1 mm of the nominal field size. Due to the fact that the jaws were adjusted properly, the dosimetric field size coincides with the geometric field size. Exceptions are very small fields, where the dosimetric field size, defined by the inclination points, becomes broader than the geometric field size. Conclusion: Profiles, particularly of small fields, have to be measured very carefully using a suitable detector. For this purpose, a detector with a negligible volume correction factor should be used. The dosimetric field size can be found by evaluating the inclination points for both WFF and FFF beams. For dosimetric purposes it is necessary to find the dosimetric size. Alternatively, if the measurements are basic data for a TPS, both, the geometric and the dosimetric sizes should be recorded.

  9. SU-E-T-813: What Is the “real” Field-Size in Photon Dosimetry?

    International Nuclear Information System (INIS)

    Gainey, M; Kollefrath, M; Saum, R; Bruggmoser, G

    2015-01-01

    Purpose: The definition of field sizes in photon dosimetry and the measurement of profiles are non-trivial. Current definitions are nominal, geometric, dosimetric (actual) or equivalent field size. In reality most detectors are not water equivalent since they contain air or high density materials. These materials can blur profiles, particularly in small fields. If necessary, detector and field size-specific volume dependent effects need to be considered. Methods: A TrueBeam-linac (Varian Medical Systems) was used. All measurements were performed within a water phantom (MP3, PTW-Freiburg), with filter (WFF) and without filter (FFF), using ionization chambers, shielded and unshielded diodes and diamond detectors. The position of the jaws was verified according to our QA-system. Field size profiles were taken at a defined depth (SSD =90 cm, SCD=100 cm). The penumbra of the profiles measured with the various detectors was compared to determine the dosimetric field size. For the evaluation of the field sizes the inclination points were also calculated. Results: The field size, both for the WFF and the FFF-mode, coincided within 1 mm of the nominal field size. Due to the fact that the jaws were adjusted properly, the dosimetric field size coincides with the geometric field size. Exceptions are very small fields, where the dosimetric field size, defined by the inclination points, becomes broader than the geometric field size. Conclusion: Profiles, particularly of small fields, have to be measured very carefully using a suitable detector. For this purpose, a detector with a negligible volume correction factor should be used. The dosimetric field size can be found by evaluating the inclination points for both WFF and FFF beams. For dosimetric purposes it is necessary to find the dosimetric size. Alternatively, if the measurements are basic data for a TPS, both, the geometric and the dosimetric sizes should be recorded

  10. Dosimetry of internal emitters - quo vadis?

    International Nuclear Information System (INIS)

    Reddy, A.R.; Nagaratnam, A.; Jain, S.C.; Gupta, M.M.; Mehta, S.C.

    1999-01-01

    The dosimetry of internally administered radiopharmaceuticals in nuclear medicine procedures using MIRD formalisms and dosimetry in the case of intakes of radionuclides and ICRP methodology for the purpose of radiological protection are well established working practices. It should, however, be remembered that dose or dose coefficients calculated refer to a reference individual, defined in terms of a mathematical phantom established on the basis of certain biokinetic reference parameters. The reference individual represents a typical caucasian adult of West Europe or North American origin. Recently, some attempts have been made to define a Reference Asian and a Reference Indian individual and to assess the effects of anatomical differences and changes in the biokinetics of radiopharmaceuticals and other radionuclides in these different reference individuals on the estimation of dose and dose coefficients in relation to the intake of internal radionuclides. The assessment of doses to the embryo/fetus due to intake of radionuclides by pregnant women, local dose estimates, microdosimetry, radiobiology and radiation protection aspects relating to Auger electron emitters represent other areas of active research in the area of dosimetry of internal emitters. The present review summarises these different aspects of work. (orig.) [de

  11. Application of the planar-scanning technique to the near-field dosimetry of millimeter-wave radiators.

    Science.gov (United States)

    Zhao, Jianxun; Lu, Hongmin; Deng, Jun

    2015-02-01

    The planar-scanning technique was applied to the experimental measurement of the electric field and power flux density (PFD) in the exposure area close to the millimeter-wave (MMW) radiator. In the near-field region, the field and PFD were calculated from the plane-wave spectrum of the field sampled on a scan plane far from the radiator. The measurement resolution was improved by reducing the spatial interval between the field samples to a fraction of half the wavelength and implementing multiple iterations of the fast Fourier transform. With the reference to the results from the numerical calculation, an experimental evaluation of the planar-scanning measurement was made for a 50 GHz radiator. Placing the probe 1 to 3 wavelengths from the aperture of the radiator, the direct measurement gave the near-field data with significant differences from the numerical results. The planar-scanning measurement placed the probe 9 wavelengths away from the aperture and effectively reduced the maximum and averaged differences in the near-field data by 70.6% and 65.5%, respectively. Applied to the dosimetry of an open-ended waveguide and a choke ring antenna for 60 GHz exposure, the technique proved useful to the measurement of the PFD in the near-field exposure area of MMW radiators. © 2015 Wiley Periodicals, Inc.

  12. Intercomparison of personnel dosimetry for thermal neutron dose equivalent in neutron and gamma-ray mixed fields

    International Nuclear Information System (INIS)

    Ogawa, Yoshihiro

    1985-01-01

    In order to consider the problems concerned with personnel dosimetry using film badges and TLDs, an intercomparison of personnel dosimetry, especially dose equivalent responses of personnel dosimeters to thermal neutron, was carried out in five different neutron and gamma-ray mixed fields at KUR and UTR-KINKI from the practical point of view. For the estimation of thermal neutron dose equivalent, it may be concluded that each personnel dosimeter has good performances in the precision, that is, the standard deviations in the measured values by individual dosimeter were within 24 %, and the dose equivalent responses to thermal neutron were almost independent on cadmium ratio and gamma-ray contamination. However, the relative thermal neutron dose equivalent of individual dosimeter normalized to the ICRP recommended value varied considerably and a difference of about 4 times was observed among the dosimeters. From the results obtained, it is suggested that the standardization of calibration factors and procedures is required from the practical point of radiation protection and safety. (author)

  13. Code for Internal Dosimetry (CINDY)

    International Nuclear Information System (INIS)

    Strenge, D.L.; Peloquin, R.A.; Sula, M.J.; Johnson, J.R.

    1990-10-01

    The CINDY (Code for Internal Dosimetry) Software Package has been developed by Pacific Northwest Laboratory to address the Department of Energy (DOE) Order 5480.11 by providing the capabilities to calculate organ dose equivalents and effective dose equivalents using the approach of International Commission on Radiological Protection (ICRP) 30. The code assist in the interpretation of bioassay data, evaluates committed and calendar-year doses from intake or bioassay measurement data, provides output consistent with revised DOE orders, is easy to use, and is generally applicable to DOE sites. Flexible biokinetics models are used to determine organ doses for annual, 50-year, calendar-year, or any other time-point dose necessary for chronic or acute intakes. CINDY is an interactive program that prompts the user to describe the cases to be analyzed and calculates the necessary results for the type of analysis being performed. Four types of analyses may be specified. 92 figs., 10 tabs

  14. Theoretical basis for dosimetry

    International Nuclear Information System (INIS)

    Carlsson, G.A.

    1985-01-01

    Radiation dosimetry is fundamental to all fields of science dealing with radiation effects and is concerned with problems which are often intricate as hinted above. A firm scientific basis is needed to face increasing demands on accurate dosimetry. This chapter is an attempt to review and to elucidate the elements for such a basis. Quantities suitable for radiation dosimetry have been defined in the unique work to coordinate radiation terminology and usage by the International Commission on Radiation Units and Measurements, ICRU. Basic definitions and terminology used in this chapter conform with the recent ''Radiation Quantities and Units, Report 33'' of the ICRU

  15. SU-F-T-434: Development of a Fan-Beam Optical Scanner Using CMOS Array for Small Field Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Brost, E; Warmington, L; Watanabe, Y [Department of Radiation Oncology, University of Minnesota, Minneapolis, MN (United States); Senthilkumar, S [Department of Physics, Vel Tech University, Chennai (India); Departamento de Ingeneria Fisica, DCI, Universidad de Guanajuato, Campus Leon, Guanajuato (Mexico)

    2016-06-15

    Purpose: To design and construct a second generation optical computed tomography (OCT) system using a fan-beam with a CMOS array detector for the 3D dosimetry with polymer gel and radiochromic solid dosimeters. The system was specifically designed for the small field dosimetry. Methods: The optical scanner used a fan-beam laser, which was produced from a collimated red laser beam (λ=620 nm) with a 15-degree laser-line generating lens. The fan-beam was sent through an index-matching bath which holds the sample stage and a sample. The emerging laser light was detected with a 2.54 cm-long CMOS array detector (512 elements). The sample stage rotated through the full 360 degree projection angles at 0.9-degree increments. Each projection was normalized to the unirradiated sample at the projection angle to correct for imperfections in the dosimeter. A larger sample could be scanned by using a motorized mirror and linearly translating the CMOS detector. The height of the sample stage was varied for a full 3D scanning. The image acquisition and motor motion was controlled by a computer. The 3D image reconstruction was accomplished by a fan-beam reconstruction algorithm. All the software was developed inhouse with MATLAB. Results: The scanner was used on both PRESAGE and PAGAT gel dosimeters. Irreconcilable refraction errors were seen with PAGAT because the fan beam laser line refracted away from the detector when the field was highly varying in 3D. With PRESAGE, this type of error was not seen. Conclusion: We could acquire tomographic images of dose distributions by the new OCT system with both polymer gel and radiochromic solid dosimeters. Preliminary results showed that the system was more suited for radiochromic solid dosimeters since the radiochromic dosimeters exhibited minimal refraction and scattering errors. We are currently working on improving the image quality by thorough characterization of the OCT system.

  16. SU-F-T-434: Development of a Fan-Beam Optical Scanner Using CMOS Array for Small Field Dosimetry

    International Nuclear Information System (INIS)

    Brost, E; Warmington, L; Watanabe, Y; Senthilkumar, S

    2016-01-01

    Purpose: To design and construct a second generation optical computed tomography (OCT) system using a fan-beam with a CMOS array detector for the 3D dosimetry with polymer gel and radiochromic solid dosimeters. The system was specifically designed for the small field dosimetry. Methods: The optical scanner used a fan-beam laser, which was produced from a collimated red laser beam (λ=620 nm) with a 15-degree laser-line generating lens. The fan-beam was sent through an index-matching bath which holds the sample stage and a sample. The emerging laser light was detected with a 2.54 cm-long CMOS array detector (512 elements). The sample stage rotated through the full 360 degree projection angles at 0.9-degree increments. Each projection was normalized to the unirradiated sample at the projection angle to correct for imperfections in the dosimeter. A larger sample could be scanned by using a motorized mirror and linearly translating the CMOS detector. The height of the sample stage was varied for a full 3D scanning. The image acquisition and motor motion was controlled by a computer. The 3D image reconstruction was accomplished by a fan-beam reconstruction algorithm. All the software was developed inhouse with MATLAB. Results: The scanner was used on both PRESAGE and PAGAT gel dosimeters. Irreconcilable refraction errors were seen with PAGAT because the fan beam laser line refracted away from the detector when the field was highly varying in 3D. With PRESAGE, this type of error was not seen. Conclusion: We could acquire tomographic images of dose distributions by the new OCT system with both polymer gel and radiochromic solid dosimeters. Preliminary results showed that the system was more suited for radiochromic solid dosimeters since the radiochromic dosimeters exhibited minimal refraction and scattering errors. We are currently working on improving the image quality by thorough characterization of the OCT system.

  17. Dosimetry of an accident in mixed field (neutrons, photons) using the spectrometry by electronic paramagnetic resonance(EPR)

    International Nuclear Information System (INIS)

    Herve, M.L.

    2006-03-01

    In a radiological accident, the assessment of the dose received by the victim is relevant information for the therapeutic strategy. Two complementary dosimetric techniques based on physical means are used in routine practice in the laboratory: EPR spectroscopy performed on materials removed from the victim or gathered from the vicinity of the victim and Monte Carlo calculations. EPR dosimetry, has been used successfully several times in cases of photon or electron overexposures. Accidental exposure may also occur with a neutron component. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials (ascorbic acid, sorbitol, glucose, galactose, fructose, mannose, lactose and sucrose). The influence of irradiation parameters (dose, dose rate, photon energy) and of environmental parameters (temperature of heating, light exposure) on the EPR signal amplitude was studied. To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of experimental reactors with different neutron to photon ratios. The relative neutron sensitivity was found to range from 10% to 43% according to the materials. Prior knowledge of the ratio between the dose in samples measured by EPR spectrometry and organ or whole body dose obtained by calculations previously performed for these different configurations, makes it possible to give a first estimation of the dose received by the victim in a short delay. The second aim of this work is to provide data relevant for a quick assessment of the dose distribution in case of accidental overexposure based on EPR measurements performed on one or several points of the body. The study consists in determining by calculation the relation between the dose to the organs and whole body and the dose to specific points of the body, like teeth, bones or samples located in the pockets of victim clothes, for different external exposures corresponding

  18. Radiation dosimetry

    International Nuclear Information System (INIS)

    Harper, M.W.; Thomas, B.; Conway, J.

    1977-01-01

    A dosemeter is described that is based on the TSCD principle (thermally stimulated current dosimetry). Basically this involves irradiating a responsive material and then heating it,whereby an electric current is produced. If the material is heated in an electric field the peak value of the thermally stimulated current or alternatively the total charge released by heating, can be related to the radiation dose received. The instrument described utilises a sheet coated with a thermoplastic polymer, such as a poly4-methylpent-l-ene. The polymer should have a softening point not lower than 150 0 C with an electrical resistivity of at least 10 16 chms/cm at 150 0 C. The polymer may also be PTFE. Heating should be in the range 150 0 C to 200 0 C and the electric field in the range 50 to 10,000V/mm. (U.K.)

  19. Dosimetry Service

    CERN Multimedia

    2006-01-01

    Cern Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry Dosimetry Service is open every morning from 8.30 - 12.00. Closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after the use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel. 7 2155 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  20. Biokinetics and dosimetric studies about 99mTc(V)DMSA distribution

    International Nuclear Information System (INIS)

    Correia, M.B.L.; Magnata, S.S.L.P.; Silva, I.M.S.; Lima, F.F.; Catanho, M.T.J.A.

    2008-01-01

    Research for radiodiagnostic agents should considerate biological critical parameters as half-life effective, target/not target uptake ratio and metabolites that together will determinate the biokinetic. Each parameter give own contribution in the absorbed dose. The dimercaptosuccinic acid (DMSA) labeled with 99m Tc(VN) is a radiopharmaceutical which has well established role in medullar thyroid carcinoma and has been proposed in complementary evaluation of bone metastasis. The aim of this work was study the biokinetics and dosimetry of 99m Tc(V)-DMSA by animal model. The 99m Tc(V)-DMSA was prepared by (III)DMSA kit alkalized. The methodology used mice, 70 days old, both males and females. The animals (n=5) received 99m Tc(V)DMSA administered IV (tail vein). After determinate times (30 min, 1h, 5h and 12h) the animals were sacrificed, the organs (blood, lungs, kidneys, muscle and bone) were excised and the activities were measured by a gamma counter. The results were evaluated based on %activity/g and the absorbed dose was estimated by extrapolation of data from animal to human, using the residence time to each organ in the MIRDOSE 3.0 program. The results show that the majority of organs reaches the top uptake at 30 min, the kidney has the greatest uptake in this time, (4.81 ± 1.38) % activity per gram, while the bone presents its highest uptake at 1h (5.49 ± 0.47)% activity per gram, after 1h all the organs had activity exponential decrease. About the absorbed dose estimated to human scale, the preliminary results showed higher value to bone, being the soft tissue dose relatively low. These dose values, however, are submitted to biological implications which are under studying yet. The biokinetic profile of 99m Tc(V)-DMSA, prepared from a DMSA kit by IPEN, was well established, allowing quantifying of residence time, while the dosimetric model presented preliminary data which directs to new analyzes

  1. JENDL Dosimetry File

    International Nuclear Information System (INIS)

    Nakazawa, Masaharu; Iguchi, Tetsuo; Kobayashi, Katsuhei; Iwasaki, Shin; Sakurai, Kiyoshi; Ikeda, Yujiro; Nakagawa, Tsuneo.

    1992-03-01

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d, n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form. (author) 76 refs

  2. JENDL Dosimetry File

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Masaharu; Iguchi, Tetsuo [Tokyo Univ. (Japan). Faculty of Engineering; Kobayashi, Katsuhei [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Iwasaki, Shin [Tohoku Univ., Sendai (Japan). Faculty of Engineering; Sakurai, Kiyoshi; Ikeda, Yujior; Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1992-03-15

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d,n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form.

  3. Field calibration of PADC track etch detectors for local neutron dosimetry in man using different radiation qualities

    Energy Technology Data Exchange (ETDEWEB)

    Haelg, Roger A., E-mail: rhaelg@phys.ethz.ch [Institute for Radiotherapy, Radiotherapie Hirslanden AG, Hirslanden Medical Center, Rain 34, CH-5000 Aarau (Switzerland); Besserer, Juergen [Institute for Radiotherapy, Radiotherapie Hirslanden AG, Hirslanden Medical Center, Rain 34, CH-5000 Aarau (Switzerland); Boschung, Markus; Mayer, Sabine [Division for Radiation Safety and Security, Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Clasie, Benjamin [Department of Radiation Oncology, Massachusetts General Hospital, 30 Fruit Street, Boston, MA 02114 (United States); Kry, Stephen F. [Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030 (United States); Schneider, Uwe [Institute for Radiotherapy, Radiotherapie Hirslanden AG, Hirslanden Medical Center, Rain 34, CH-5000 Aarau (Switzerland); Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 204, CH-8057 Zurich (Switzerland)

    2012-12-01

    In order to quantify the dose from neutrons to a patient for contemporary radiation treatment techniques, measurements inside phantoms, representing the patient, are necessary. Published reports on neutron dose measurements cover measurements performed free in air or on the surface of phantoms and the doses are expressed in terms of personal dose equivalent or ambient dose equivalent. This study focuses on measurements of local neutron doses inside a radiotherapy phantom and presents a field calibration procedure for PADC track etch detectors. An initial absolute calibration factor in terms of H{sub p}(10) for personal dosimetry is converted into neutron dose equivalent and additional calibration factors are derived to account for the spectral changes in the neutron fluence for different radiation therapy beam qualities and depths in the phantom. The neutron spectra used for the calculation of the calibration factors are determined in different depths by Monte Carlo simulations for the investigated radiation qualities. These spectra are used together with the energy dependent response function of the PADC detectors to account for the spectral changes in the neutron fluence. The resulting total calibration factors are 0.76 for a photon beam (in- and out-of-field), 1.00 (in-field) and 0.84 (out-of-field) for an active proton beam and 1.05 (in-field) and 0.91 (out-of-field) for a passive proton beam, respectively. The uncertainty for neutron dose measurements using this field calibration method is less than 40%. The extended calibration procedure presented in this work showed that it is possible to use PADC track etch detectors for measurements of local neutron dose equivalent inside anthropomorphic phantoms by accounting for spectral changes in the neutron fluence.

  4. Metrological legal frame in the field of the photon dosimetry of radiotherapy in Cuba

    International Nuclear Information System (INIS)

    Walwyn S, G.; Gutierrez L, S.; Gonzalez R, N.

    2006-01-01

    The Clinical Dosimetry in the planning of the doses to administer to patients under radiant treatment is of great importance. At the moment the clinical dosemeters its are manufactured with a high technology but errors of production or manipulation cannot be discarded that lead to errors in this planning. It also exists, a group of metrological and of operation parameters that are not checked in a routine calibration, and for those that are checked, legal base that restricts its use in cases of bad operation doesn't exist. This motivated to the Cuban standard elaboration NC 352:2005, for the verification of reference dosemeters of radiotherapy, process that trafficked for an exhaustive search and study of standards and international technical reports, selecting as base document, the standard IEC 60731:1997, for essays of approval of model of clinical dosemeters used in radiotherapy. The present article shows the main technical aspects considered and the requirements and verification methods for the declaration of aptitude of the dosemeters. This document constitutes the scientific base for the implementation from a verification service to national level and an important contribution to the standardization of the metrology of ionizing radiations of Cuba. (Author)

  5. Use of novel fibre-coupled radioluminescence and RADPOS dosimetry systems for total scatter factor measurements in small fields

    DEFF Research Database (Denmark)

    Ploquin, N.; Kertzscher, Gustavo; Vandervoort, E.

    2015-01-01

    A dosimetry system based on Al2O3:C radioluminescence (RL), and RADPOS, a novel 4D dosimetry system using microMOSFETs, were used to measure total scatter factors, (Sc,p)fclindet, for the CyberKnife robotic radiosugery system. New Monte Carlo calculated correction factors are presented and applied...

  6. Textbook of dosimetry. 4. ed.

    International Nuclear Information System (INIS)

    Ivanov, V.I.

    1999-01-01

    This textbook of dosimetry is devoted to the students in physics and technical physics of high education institutions, confronted with different application of atomic energy as well as with protection of population and environment against ionizing radiations. Atomic energy is highly beneficial for man but unfortunately incorporates potential dangers which manifest in accidents, the source of which is either insufficient training of the personnel, a criminal negligence or insufficient reliability of the nuclear facilities. The majority of the incident and accident events have had as origin the personnel errors. This was the case with both the 'Three Miles Island' (1979) and Chernobyl (1986) NPP accidents. The dosimetry science acquires a vital significance in accident situations since the data obtained by its procedures are essential in choosing the correct immediate actions, behaviour tactics, orientation of liquidation of accident consequences as well as in ensuring the health of population. An important accent is placed in this manual on clarification of the nature of physical processes taken place in dosimetric detectors, in establishing the relation between radiation field characteristics and the detector response as well as in defining different dosimetric quantities. The terminology and the units of physical quantities is based on the international system of units. The book contains the following 15 chapters: 1. Ionizing radiation field; 2. Radiation doses; 3. Physical bases of gamma radiation dosimetry; 4. Ionization dosimetric detectors; 5. Semiconductor dosimetric detectors; 6. Scintillation detection in the gamma radiation dosimetry; 7. Luminescent methods in dosimetry; 8. The photographic and chemical methods of gamma radiation dosimetry; 9. Neutron dosimetry; 10. Dosimetry of high intensity radiation; 11. Dosimetry of high energy Bremsstrahlung; 12. Measurement of the linear energy transfer; 13. Microdosimetry; 14. Dosimetry of incorporated

  7. Evaluation of a liquid ionization chamber for relative dosimetry in small and large fields of radiotherapy photon beams

    International Nuclear Information System (INIS)

    Benítez, E.M.; Casado, F.J.; García-Pareja, S.; Martín-Viera, J.A.; Moreno, C.; Parra, V.

    2013-01-01

    Commissioning and quality assurance of radiotherapy linear accelerators require measurement of the absorbed dose to water, and a wide range of detectors are available for absolute and relative dosimetry in megavoltage beams. In this paper, the PTW microLion isooctane-filled ionization chamber has been tested to perform relative measurements in a 6 MV photon beam from a linear accelerator. Output factors, percent depth dose and dose profiles have been obtained for small and large fields. These quantities have been compared with those from usual detectors in the routine practice. In order to carry out a more realistic comparison, an uncertainty analysis has been developed, taking type A and B uncertainties into account. The results present microLion as a good option when high spatial resolution is needed, thanks to its reduced sensitive volume. The liquid filling also provides a high signal compared to other detectors, like that based on air filling. Furthermore, the relative response of microLion when field size is varied suggests that this detector has energy dependence, since it is appreciated an over-response for small fields and an under-response for the large ones. This effect is more obvious for field sizes wider than 20 × 20 cm 2 , where the differences in percent depth dose at great depths exceed the uncertainties estimated in this study. - Highlights: • When high spatial resolution is required the results confirm the suitability of the liquid chamber. • Some energy dependence of the liquid detector can be appreciated in OFs and PDDs for small and large fields. • For field sizes >20 × 20 cm 2 , the differences in PDDs at great depths exceed the uncertainties estimated. • Some drawbacks should be considered: the time to reach stability, the high voltage supply required and the acquiring cost

  8. The biokinetic of incorporates radionuclides; Die Biokinetik von inkorporierten Radionukliden

    Energy Technology Data Exchange (ETDEWEB)

    Breustedt, Bastian [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Strahlenforschung; Giussani, Augusto [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Arbeitsgruppe ' ' Externe und interne Dosimetrie, Biokinetik' '

    2017-08-01

    Incorporated radionuclides from nuclear accidents, fission product releases or nuclear medical administration are distributed in the human body in organs and tissue, absorbed 9or excreted. The interpretation of incorporation monitoring results and the estimation of the internal doses that cannot be measured directly need mathematical methods and the formulation of biokinetic models.

  9. The biokinetics of ruthenium in the human body

    International Nuclear Information System (INIS)

    Leggett, Richard Wayne

    2011-01-01

    The biokinetics of ruthenium (Ru) in the human body is of interest due mainly to the potential for occupational or environmental exposure to 106Ru (T1/2 = 373.6 d) and 103Ru (T1/2 = 39.3 d), which typically represent a significant portion of the fission products in a reactor inventory. During reactor operations or nuclear fuel reprocessing these ruthenium isotopes may be present as ruthenium tetroxide (RuO4) vapor, a highly mobile form of ruthenium that has been involved in a number of cases of accidental exposure to 106Ru or 103Ru. This paper summarizes the biokinetic database for ruthenium and proposes a new respiratory model for inhaled RuO4 vapor, a new biokinetic for systemic (absorbed) ruthenium, and material-specific gastrointestinal absorption fractions for ruthenium. The proposed respiratory model for RuO4 differs from the current ICRP model mainly in that it depicts slower clearance of deposited activity from the respiratory tract and lower absorption to blood than depicted in the current ICRP model. The proposed systemic biokinetic model depicts more realistic paths of movement of absorbed ruthenium in the body than the current ICRP model and, in contrast to the present model, a less uniform distribution of systemic activity. Implications of the proposed models with regard to inhalation and ingestion dose coefficients for 106Ru are examined.

  10. Biokinetics – the development of a health profession from physical ...

    African Journals Online (AJOL)

    Biokinetics – the development of a health profession from physical education - a historical perspective. ... In this respect some medical aid funds supported this philosophy of health promotion, as the curative treatment of health problems are becoming increasingly expensive and are burdening health-care costs. At present ...

  11. Tissue interfaces dosimetry in small field radiotherapy with alanine/EPR mini dosimeters and Monte Carlo-Penelope simulation

    Energy Technology Data Exchange (ETDEWEB)

    Vega R, J. L.; Nicolucci, P.; Baffa, O. [Universidade de Sao Paulo, FFCLRP, Departamento de Fisica, Av. Bandeirantes 3900, Bairro Monte Alegre, 14040-901 Ribeirao Preto, Sao Paulo (Brazil); Chen, F. [Universidade Federale do ABC, CCNH, Rua Santa Adelia 166, Bangu, 09210-170 Santo Andre, Sao Paulo (Brazil); Apaza V, D. G., E-mail: josevegaramirez@yahoo.es [Universidad Nacional de San Agustin de Arequipa, Departamento de Fisica, Arequipa (Peru)

    2014-08-15

    The dosimetry system based on alanine mini dosimeters plus K-Band EPR spectrometer was tested in the tissue-interface dosimetry through the percentage depth-dose (Pdd) determination for 3 x 3 cm{sup 2} and 1 x 1 cm{sup 2} radiation fields sizes. The alanine mini dosimeters were produced by mechanical pressure from a mixture of 95% L-alanine and 5% polyvinyl alcohol (Pva) acting as binder. Nominal dimensions of these mini dosimeters were 1 mm diameter and 3 mm length as well as 3 - 4 mg mass. The EPR spectra of the mini dosimeters were registered using a K-Band (24 GHz) EPR spectrometer. The mini dosimeters were placed in a nonhomogeneous phantom and irradiated with 20 Gy in a 6 MV PRIMUS Siemens linear accelerator, with a source-to-surface distance of 100 cm using the small fields previously mentioned. The cylindrical non-homogeneous phantom was comprised of several disk-shaped plates of different materials in the sequence acrylic-bone cork-bone-acrylic, with dimensions 15 cm diameter and 1 cm thick. The plates were placed in descending order, starting from top with four acrylic plates followed by two bone plates plus eight cork plates plus two bone plates and finally, four acrylic plates (4-2-8-2-4). Pdd curves from the treatment planning system and from Monte Carlo simulation with Penelope code were determined. Mini dosimeters Pdd results show good agreement with Penelope, better than 95% for the cork homogeneous region and 97.7% in the bone heterogeneous region. In the first interface region, between acrylic and bone, it can see a dose increment of 0.6% for mini dosimeters compared to Penelope. At the second interface, between bone and cork, there is 9.1% of dose increment for mini dosimeter relative to Penelope. For the third (cork-bone) and fourth (bone-acrylic) interfaces, the dose increment for mini dosimeters compared to Penelope was 4.1% both. (Author)

  12. Tissue interfaces dosimetry in small field radiotherapy with alanine/EPR mini dosimeters and Monte Carlo-Penelope simulation

    International Nuclear Information System (INIS)

    Vega R, J. L.; Nicolucci, P.; Baffa, O.; Chen, F.; Apaza V, D. G.

    2014-08-01

    The dosimetry system based on alanine mini dosimeters plus K-Band EPR spectrometer was tested in the tissue-interface dosimetry through the percentage depth-dose (Pdd) determination for 3 x 3 cm 2 and 1 x 1 cm 2 radiation fields sizes. The alanine mini dosimeters were produced by mechanical pressure from a mixture of 95% L-alanine and 5% polyvinyl alcohol (Pva) acting as binder. Nominal dimensions of these mini dosimeters were 1 mm diameter and 3 mm length as well as 3 - 4 mg mass. The EPR spectra of the mini dosimeters were registered using a K-Band (24 GHz) EPR spectrometer. The mini dosimeters were placed in a nonhomogeneous phantom and irradiated with 20 Gy in a 6 MV PRIMUS Siemens linear accelerator, with a source-to-surface distance of 100 cm using the small fields previously mentioned. The cylindrical non-homogeneous phantom was comprised of several disk-shaped plates of different materials in the sequence acrylic-bone cork-bone-acrylic, with dimensions 15 cm diameter and 1 cm thick. The plates were placed in descending order, starting from top with four acrylic plates followed by two bone plates plus eight cork plates plus two bone plates and finally, four acrylic plates (4-2-8-2-4). Pdd curves from the treatment planning system and from Monte Carlo simulation with Penelope code were determined. Mini dosimeters Pdd results show good agreement with Penelope, better than 95% for the cork homogeneous region and 97.7% in the bone heterogeneous region. In the first interface region, between acrylic and bone, it can see a dose increment of 0.6% for mini dosimeters compared to Penelope. At the second interface, between bone and cork, there is 9.1% of dose increment for mini dosimeter relative to Penelope. For the third (cork-bone) and fourth (bone-acrylic) interfaces, the dose increment for mini dosimeters compared to Penelope was 4.1% both. (Author)

  13. Miniature semiconductor detectors for in vivo dosimetry

    International Nuclear Information System (INIS)

    Rosenfeld, A. B.; Cutajar, D.; Lerch, M. L. F.; Takacs, G.; Cornelius, I. M.; Yudelev, M.; Zaider, M.

    2006-01-01

    Silicon mini-semiconductor detectors are found in wide applications for in vivo personal dosimetry and dosimetry and Micro-dosimetry of different radiation oncology modalities. These applications are based on integral and spectroscopy modes of metal oxide semiconductor field effect transistor and silicon p-n junction detectors. The advantages and limitations of each are discussed. (authors)

  14. SU-E-T-423: TrueBeam Small Field Dosimetry Using Commercial Plastic Scintillation and Other Stereotactic Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Pino, R [Houston Methodist Hospital, Houston, TX (United States); Therriault-Proulx, F; Wang, X; Yang, J; Beddar, S [University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-01

    Purpose: To perform dose profile and output factor (OF) measurements with the Exradin W1 plastic scintillation detector (PSD) for small fields made by the high-definition multi-leaf collimator (MLC) on the TrueBeam STx system and to compare them to values measured with an IBA CC01 ionization chamber and a Sun Nuclear Edge detector diode for 6 MV photon beams. Methods: The Exradin W1 is a new small volume near-water equivalent and energy independent PSD manufactured by Standard Imaging, Inc. All measurements were performed in an IBA Blue Phantom water tank. Square MLC-shaped fields with sides ranging from 0.5 cm to 2 cm and jawshaped fields with sides ranging from 1 cm to 40 cm were measured using an SAD setup at 10 cm depth. Dose profile and percent depth dose (PDD) measurements were also taken under the same conditions for MLC fields 0.5×0.5 and 1×1 cm2 in size with jaws at 2×2cm2. The CC01 and W1 were vertically mounted. Results: OFs measured with the W1 for jaw only square fields were consistent with the ones measured with a Farmers PTW TN33013 ion chamber (1.8% maximum deviation). OF and penumbra measurement results are presented below. PDDs measured for all detectors are within 1.5% for the 0.5×0.5 cm2 and within 1% for the 1×1 cm2 MLC fields.Output factors:MLC size W1 CC01 EDGE0.5cm 0.555 0.541 0.5851.0cm 0.716 0.702 0.7331.5cm 0.779 0.761 0.7772.0cm 0.804 0.785 0.796Penumbras (mm):MLC size W1 CC01 EDGE0.5cm 2.7 2.9 2.51.0cm 3.0 3.4 2. Conclusion: OFs measured for small MLC fields were consistent with the ones measured with the other stereotactic detectors. Measured penumbras are consistent with detector size. The Exradin W1 PSD is an excellent choice for characterizing MLC-shaped small beam dosimetry used for stereotactic radiosurgery and body radiation therapy. Sam Beddar would like to disclose a NIH/NCI SBIR Phase II grant (2R44CA153824-02A1) with Standard Imaging, Title: “Water-Equivalent Plastic Scintillation Detectors for Small Field

  15. SU-E-T-423: TrueBeam Small Field Dosimetry Using Commercial Plastic Scintillation and Other Stereotactic Detectors

    International Nuclear Information System (INIS)

    Pino, R; Therriault-Proulx, F; Wang, X; Yang, J; Beddar, S

    2014-01-01

    Purpose: To perform dose profile and output factor (OF) measurements with the Exradin W1 plastic scintillation detector (PSD) for small fields made by the high-definition multi-leaf collimator (MLC) on the TrueBeam STx system and to compare them to values measured with an IBA CC01 ionization chamber and a Sun Nuclear Edge detector diode for 6 MV photon beams. Methods: The Exradin W1 is a new small volume near-water equivalent and energy independent PSD manufactured by Standard Imaging, Inc. All measurements were performed in an IBA Blue Phantom water tank. Square MLC-shaped fields with sides ranging from 0.5 cm to 2 cm and jawshaped fields with sides ranging from 1 cm to 40 cm were measured using an SAD setup at 10 cm depth. Dose profile and percent depth dose (PDD) measurements were also taken under the same conditions for MLC fields 0.5×0.5 and 1×1 cm2 in size with jaws at 2×2cm2. The CC01 and W1 were vertically mounted. Results: OFs measured with the W1 for jaw only square fields were consistent with the ones measured with a Farmers PTW TN33013 ion chamber (1.8% maximum deviation). OF and penumbra measurement results are presented below. PDDs measured for all detectors are within 1.5% for the 0.5×0.5 cm2 and within 1% for the 1×1 cm2 MLC fields.Output factors:MLC size W1 CC01 EDGE0.5cm 0.555 0.541 0.5851.0cm 0.716 0.702 0.7331.5cm 0.779 0.761 0.7772.0cm 0.804 0.785 0.796Penumbras (mm):MLC size W1 CC01 EDGE0.5cm 2.7 2.9 2.51.0cm 3.0 3.4 2. Conclusion: OFs measured for small MLC fields were consistent with the ones measured with the other stereotactic detectors. Measured penumbras are consistent with detector size. The Exradin W1 PSD is an excellent choice for characterizing MLC-shaped small beam dosimetry used for stereotactic radiosurgery and body radiation therapy. Sam Beddar would like to disclose a NIH/NCI SBIR Phase II grant (2R44CA153824-02A1) with Standard Imaging, Title: “Water-Equivalent Plastic Scintillation Detectors for Small Field

  16. Dosimetry of Exposure to Electromagnetic Fields in Daily Life and Medical Applications

    NARCIS (Netherlands)

    J.F. Bakker (Jurriaan)

    2012-01-01

    textabstractElectromagnetic fields (EMF) are present everywhere in our environment but are usually invisible to the human eye. EMF for example generated by mobile phones and 50Hz power lines, can cause electric fields, currents and tissue heating in the human body. In the past, exposure limits were

  17. ESR Dosimetry

    International Nuclear Information System (INIS)

    Baffa, Oswaldo; Rossi, Bruno; Graeff, Carlos; Kinoshita, Angela; Chen Abrego, Felipe; Santos, Adevailton Bernardo dos

    2004-01-01

    ESR dosimetry is widely used for several applications such as dose assessment in accidents, medical applications and sterilization of food and other materials. In this work the dosimetric properties of natural and synthetic Hydroxyapatite, Alanine, and 2-Methylalanine are presented. Recent results on the use of a K-Band (24 GHz) ESR spectrometer in dosimetry are also presented

  18. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 7 2155 http://cern.ch/rp-dosimetry

  19. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service Tel. 7 2155 http://cern.ch/rp-dosimetry

  20. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 72155 http://cern.ch/rp-dosimetry

  1. Dosimetry of normal and wedge fields for a cobalt-60 teletherapy unit

    International Nuclear Information System (INIS)

    Tripathi, U.B.; Kelkar, N.Y.

    1980-01-01

    A simple analytical method for computation of dose distributions for normal and wedge fields is described and the use of the method in planning radiation treatment is outlined. Formulas has been given to compute: (1) depth dose along central axis of cobalt-60 beam, (2) dose to off-axis points, and (3) dose distribution for a wedge field. Good agreement has been found between theoretical and experimental values. With the help of these formulae, the dose at any point can be easily and accurately calculated and radiotherapy can be planned for tumours of very odd shape and sizes. The limitation of the method is that the formulae have been derived for 50% field definition. For cobalt-60 machine having any other field definition, appropriate correction factors have to be applied. (M.G.B.)

  2. Bayesian model selection validates a biokinetic model for zirconium processing in humans

    Science.gov (United States)

    2012-01-01

    Background In radiation protection, biokinetic models for zirconium processing are of crucial importance in dose estimation and further risk analysis for humans exposed to this radioactive substance. They provide limiting values of detrimental effects and build the basis for applications in internal dosimetry, the prediction for radioactive zirconium retention in various organs as well as retrospective dosimetry. Multi-compartmental models are the tool of choice for simulating the processing of zirconium. Although easily interpretable, determining the exact compartment structure and interaction mechanisms is generally daunting. In the context of observing the dynamics of multiple compartments, Bayesian methods provide efficient tools for model inference and selection. Results We are the first to apply a Markov chain Monte Carlo approach to compute Bayes factors for the evaluation of two competing models for zirconium processing in the human body after ingestion. Based on in vivo measurements of human plasma and urine levels we were able to show that a recently published model is superior to the standard model of the International Commission on Radiological Protection. The Bayes factors were estimated by means of the numerically stable thermodynamic integration in combination with a recently developed copula-based Metropolis-Hastings sampler. Conclusions In contrast to the standard model the novel model predicts lower accretion of zirconium in bones. This results in lower levels of noxious doses for exposed individuals. Moreover, the Bayesian approach allows for retrospective dose assessment, including credible intervals for the initially ingested zirconium, in a significantly more reliable fashion than previously possible. All methods presented here are readily applicable to many modeling tasks in systems biology. PMID:22863152

  3. The alanine detector in BNCT dosimetry: dose response in thermal and epithermal neutron fields.

    Science.gov (United States)

    Schmitz, T; Bassler, N; Blaickner, M; Ziegner, M; Hsiao, M C; Liu, Y H; Koivunoro, H; Auterinen, I; Serén, T; Kotiluoto, P; Palmans, H; Sharpe, P; Langguth, P; Hampel, G

    2015-01-01

    The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a (60)Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes fluka and mcnp. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen & Olsen alanine response model. The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. The alanine detector can be used without

  4. Optimization of electret ionization chambers for dosimetry in mixed neutron-gamma fields

    International Nuclear Information System (INIS)

    Doerschel, B.; Pretzsch, G.

    1984-01-01

    The properties of combination dosemeters consisting of two air-filled electret ionization chambers in mixed neutron-gamma fields have been investigated. The first chamber, polyethylene-walled, is sensitive to neutrons and gamma rays, the second, having walls of teflon, is sensitive to gamma rays only. The properties of the dosemeters are determined by the resulting errors and the measuring range. As both properties depend on the dimensions of the electret ionization chambers they have been taken into account in optimizing the dimensions. The results show that with the use of the dosemeters the effective dose equivalent in mixed neutron-gamma fields can be determined nearly independently of the spectra. The lower detection limit is less than 1 mSv and the maximum uncertainty of dose measurements about 12%. (author)

  5. Reference and standard benchmark field consensus fission yields for U.S. reactor dosimetry programs

    International Nuclear Information System (INIS)

    Gilliam, D.M.; Helmer, R.G.; Greenwood, R.C.; Rogers, J.W.; Heinrich, R.R.; Popek, R.J.; Kellogg, L.S.; Lippincott, E.P.; Hansen, G.E.; Zimmer, W.H.

    1977-01-01

    Measured fission product yields are reported for three benchmark neutron fields--the BIG-10 fast critical assembly at Los Alamos, the CFRMF fast neutron cavity at INEL, and the thermal column of the NBS Research Reactor. These measurements were carried out by participants in the Interlaboratory LMFBR Reaction Rates (ILRR) program. Fission product generation rates were determined by post-irradiation analysis of gamma-ray emission from fission activation foils. The gamma counting was performed by Ge(Li) spectrometry at INEL, ANL, and HEDL; the sample sent to INEL was also analyzed by NaI(Tl) spectrometry for Ba-140 content. The fission rates were determined by means of the NBS Double Fission Ionization Chamber using thin deposits of each of the fissionable isotopes. Four fissionable isotopes were included in the fast neutron field measurements; these were U-235, U-238, Pu-239, and Np-237. Only U-235 was included in the thermal neutron yield measurements. For the fast neutron fields, consensus yields were determined for three fission product isotopes--Zr-95, Ru-103, and Ba-140. For these fission product isotopes, a separately activated foil was analyzed by each of the three gamma counting laboratories. The experimental standard deviation of the three independent results was typically +- 1.5%. For the thermal neutron field, a consensus value for the Cs-137 yield was also obtained. Subsidiary fission yields are also reported for other isotopes which were studied less intensively (usually by only one of the participating laboratories). Comparisons with EBR-II fast reactor yields from destructive analysis and with ENDF/B recommended values are given

  6. SU-F-T-577: Comparison of Small Field Dosimetry Measurements in Fields Shaped with Conical Applicators On Two Different Accelerating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Muir, B; McEwen, M [National Research Council, Ottawa, ON (Canada); Belec, J; Vandervoort, E [Ottawa Hospital General Campus, Ottawa, ON (Canada); Christiansen, E [Carleton University, Ottawa, ON (Canada)

    2016-06-15

    Purpose: To investigate small field dosimetry measurements and associated uncertainties when conical applicators are used to shape treatment fields from two different accelerating systems. Methods: Output factor measurements are made in water in beams from the CyberKnife radiosurgery system, which uses conical applicators to shape fields from a (flattening filter-free) 6 MV beam, and in a 6 MV beam from the Elekta Precise linear accelerator (with flattening filter) with BrainLab external conical applicators fitted to shape the field. The measurements use various detectors: (i) an Exradin A16 ion chamber, (ii) two Exradin W1 plastic scintillation detectors, (iii) a Sun Nuclear Edge diode, and (iv) two PTW microDiamond synthetic diamond detectors. Profiles are used for accurate detector positioning and to specify field size (FWHM). Output factor measurements are corrected with detector specific correction factors taken from the literature where available and/or from Monte Carlo simulations using the EGSnrc code system. Results: Differences in measurements of up to 1.7% are observed with a given detector type in the same beam (i.e., intra-detector variability). Corrected results from different detectors in the same beam (inter-detector differences) show deviations up to 3 %. Combining data for all detectors and comparing results from the two accelerators results in a 5.9% maximum difference for the smallest field sizes (FWHM=5.2–5.6 mm), well outside the combined uncertainties (∼1% for the smallest beams) and/or differences among detectors. This suggests that the FWHM of a measured profile is not a good specifier to compare results from different small fields with the same nominal energy. Conclusion: Large differences in results for both intra-detector variability and inter-detector differences suggest potentially high uncertainties in detector-specific correction factors. Differences between the results measured in circular fields from different accelerating

  7. Dosimetry performed on inverted 'Y' field for radiotherapy of Hodgkin's disease

    International Nuclear Information System (INIS)

    Dorsch, G.

    1984-01-01

    Examinations with integrated spleen volume on the Alderson phantom were performed with photon rays of the telecobalt device and linear accelerators with 6 and 10 MeV limit energy. Concerning radiation quality and field homogeneity, 10 MeV linear accelerators are to be preferred. Exposure of one third of the leftside kidney to damaging radiation doses obtain with spleen irradiation only. Lumbar spinal marrow can be protected against radiation damage by using dorsal absorbers from 20 Gy focal dose onwards. Craniolateral oophoropexy has to be performed prior to irradiation in order to maintain ovary functions. (DG) [de

  8. The biokinetics of uranium migrating from embedded DU fragments

    International Nuclear Information System (INIS)

    Leggett, R.W.; Pellmar, T.C.

    2003-01-01

    Military uses of depleted uranium (DU) munitions have resulted in casualties with embedded DU fragments. Assessment of radiological or chemical health risks from these fragments requires a model relating urinary U to the rate of migration of U from the fragments, and its accumulation in systemic tissues. A detailed biokinetic model for U has been published by the International Commission on Radiological Protection (ICRP), but its applicability to U migrating from embedded DU fragments is uncertain. Recently, ) conducted a study at the Armed Forces Radiobiology Research Institute (AFRRI) on the redistribution and toxicology of U in rats with implanted DU pellets, simulating embedded fragments. This paper compares the biokinetic data from that study with the behavior of commonly studied forms of U in rats (e.g., intravenously injected U nitrate). The comparisons indicate that the biokinetics of U migrating from embedded DU is similar to that of commonly studied forms of U with regard to long-term accumulation in kidneys, bone, and liver. The results provide limited support for the application of the ICRP's model to persons with embedded DU fragments. Additional information is needed with regard to the short-term behavior of migrating U and its accumulation in lymph nodes, brain, testicles, and other infrequently studied U repositories

  9. Comparison of film dosimetry and Monte Carlo simulations in small field IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.R.; Suh, T.S.; Choe, B.Y.; Lee, H.K. [The Catholic Univ., Seoul (Korea, Republic of); Sohn. Jason W. [Washington Univ., St. Louis (United States)

    2002-07-01

    Intensity modulated radiation therapy(IMRT) is a recent useful technique that conforms a high dose to the target volume while restricting dose to the surrounding critical organs. In IMRT, the small size beam let is used for intensity modulation. Thus, dose calculation in small field is very important. But, dose calculation in small field is not accurate in recent RTP system because electronic disequilibrium and the effect of multiple scattering electron are not considered in dose calculation. and therefore, We have evaluated the errors of depth dose and beam profile between measurement data and Monte Carlo simulation. With a homogeneous phantom and two heterogeneous phantoms, A thermoluminescent dosimeter (TLD) and radiochromic films have been selected for dose measurement in 6 MV photon beams. A linear accelerator Varian 2300C (Varian Medical Systems, USA) equipped with a multileaf collimator have been used in dose measurement. The results of simulations using the Monte Carlo systems BEAM/EGS4 (NRC, Canada) to model the beam geometry have been compared with dose measurements. Generally good agreements were found between measurements and dose calculations of Monte Carlo simulation. But some discrepancies were found in this study. Thus further study will be needed to compensate these errors.

  10. Verification of the plan dosimetry for high dose rate brachytherapy using metal-oxide-semiconductor field effect transistor detectors

    International Nuclear Information System (INIS)

    Qi Zhenyu; Deng Xiaowu; Huang Shaomin; Lu Jie; Lerch, Michael; Cutajar, Dean; Rosenfeld, Anatoly

    2007-01-01

    The feasibility of a recently designed metal-oxide-semiconductor field effect transistor (MOSFET) dosimetry system for dose verification of high dose rate (HDR) brachytherapy treatment planning was investigated. MOSFET detectors were calibrated with a 0.6 cm 3 NE-2571 Farmer-type ionization chamber in water. Key characteristics of the MOSFET detectors, such as the energy dependence, that will affect phantom measurements with HDR 192 Ir sources were measured. The MOSFET detector was then applied to verify the dosimetric accuracy of HDR brachytherapy treatments in a custom-made water phantom. Three MOSFET detectors were calibrated independently, with the calibration factors ranging from 0.187 to 0.215 cGy/mV. A distance dependent energy response was observed, significant within 2 cm from the source. The new MOSFET detector has a good reproducibility ( 2 =1). It was observed that the MOSFET detectors had a linear response to dose until the threshold voltage reached approximately 24 V for 192 Ir source measurements. Further comparison of phantom measurements using MOSFET detectors with dose calculations by a commercial treatment planning system for computed tomography-based brachytherapy treatment plans showed that the mean relative deviation was 2.2±0.2% for dose points 1 cm away from the source and 2.0±0.1% for dose points located 2 cm away. The percentage deviations between the measured doses and the planned doses were below 5% for all the measurements. The MOSFET detector, with its advantages of small physical size and ease of use, is a reliable tool for quality assurance of HDR brachytherapy. The phantom verification method described here is universal and can be applied to other HDR brachytherapy treatments

  11. Dose absorbed in adults and children thyroid due to the I123 using the dosimetry MIRD and Marinelli

    International Nuclear Information System (INIS)

    Vasquez, M.; Castillo, C.; Cabrera, C.; Sarachaga, R.; Castaneda, J.; Diaz, E.

    2014-08-01

    Using the dosimetry MIRD, and representation Cristy-Eckerman in the thyroid gland and organs of their bio-kinetics when I 123 (Iodine) is used, the study demonstrates that the absorbed dose by the gland of an adult, children, and newly born, is their auto-dose, independent of the compartments number of their bio-kinetics. The dosimetric contributions of the organs of their bio-kinetics are insignificant. Their results are not significantly different to those obtained by the formalism MARINELLI (auto-dose) when it uses a sphere like glandular representation. In consequence, the kinetic model corresponding to the glandular representation decreases to a compartment, where the gland can also be represented like a sphere. (Author)

  12. Dosimetry in Japanese male and female models for a low-frequency electric field

    International Nuclear Information System (INIS)

    Hirata, Akimasa; Fujiwara, Osamu

    2007-01-01

    The present study quantified induced current in anatomically based Japanese male and female models for exposure to low-frequency electric fields. A quasi-static finite-difference time-domain (FDTD) method was applied to analyze this problem. For our computational results, the difference of the induced current density averaged over an area of 1 cm 2 between Japanese male and female models was less than 30% for each nerve tissue. The difference of induced current density between the present study and earlier works was less than 50% for the same conductivities, despite the different morphology. Particularly, maximum current density in central nerve tissues appeared in the retina of Japanese models, the same as in the earlier works. (note)

  13. Evaluation of individual dosimetry in mixed neutron and photon radiation fields (EVIDOS). Part II: conclusions and recommendations

    International Nuclear Information System (INIS)

    Schuhmacher, H.; Luszik-Bhadra, M.; Reginatto, M.; Bartlett, D.; Tanner, R.; Bolognese-Milsztajn, T.; Lacoste, V.; Boschung, M.; Fiechtner, A.; Coeck, M.; Vanhavere, F.; Curzio, G.; Errico d', F.; Kylloenen, J.-E.; Lindborg, L.

    2005-01-01

    Full text: The EVIDOS project, supported by the European Commission within the 5th Framework Programme, aims at evaluating state of the art dosimetry techniques in representative work-places of the nuclear industry. Seven European institutes with recognized expertise in radiation protection instruments and methods joined efforts with end users at nuclear power plants, at fuel processing and reprocessing plants, and at transport and storage facilities. A particular task of the project was to develop methods to characterize the neutron component of mixed radiation fields at workplaces and to derive reference values of radiation protection quantities from energy and direction distributions of the neutron fluence. While other presentations at this workshop describe the methods developed and the instruments used, this presentation will summarize the main results, draw conclusions and discuss recommendations relevant to routine monitoring. The final results from the project include a catalogue with spectra and dosimetric data for 14 different workplace fields (boiling water reactor, pressurized water reactor, research reactor, fuel processing, storage of spent fuel), instruments and procedures to derive reference values for personal dose equivalent and other radiation protection quantities, and novel personal dosemeters for mixed radiation and results on their dosimetric and technical performance. A number of questions will be addressed in the presentation, including: which methods allow to determine H*(10) and H p (10) in complex mixed n/γ radiation fields with acceptable uncertainty?; what is the influence of the energy and direction distributions of neutrons on the ratios between H*(10), H p (10) and E?; how much do the readings of area monitors deviate from H*(10) and do they give conservative estimates of H p (10) and E?; how much do the readings of personal dosemeters deviate from H p (10) and do they give conservative estimates of E?; do new active (electronic

  14. Monte Carlo simulation of mixed neutron-gamma radiation fields and dosimetry devices

    International Nuclear Information System (INIS)

    Zhang, Guoqing

    2011-01-01

    Monte Carlo methods based on random sampling are widely used in different fields for the capability of solving problems with a large number of coupled degrees of freedom. In this work, Monte Carlos methods are successfully applied for the simulation of the mixed neutron-gamma field in an interim storage facility and neutron dosimeters of different types. Details are discussed in two parts: In the first part, the method of simulating an interim storage facility loaded with CASTORs is presented. The size of a CASTOR is rather large (several meters) and the CASTOR wall is very thick (tens of centimeters). Obtaining the results of dose rates outside a CASTOR with reasonable errors costs usually hours or even days. For the simulation of a large amount of CASTORs in an interim storage facility, it needs weeks or even months to finish a calculation. Variance reduction techniques were used to reduce the calculation time and to achieve reasonable relative errors. Source clones were applied to avoid unnecessary repeated calculations. In addition, the simulations were performed on a cluster system. With the calculation techniques discussed above, the efficiencies of calculations can be improved evidently. In the second part, the methods of simulating the response of neutron dosimeters are presented. An Alnor albedo dosimeter was modelled in MCNP, and it has been simulated in the facility to calculate the calibration factor to get the evaluated response to a Cf-252 source. The angular response of Makrofol detectors to fast neutrons has also been investigated. As a kind of SSNTD, Makrofol can detect fast neutrons by recording the neutron induced heavy charged recoils. To obtain the information of charged recoils, general-purpose Monte Carlo codes were used for transporting incident neutrons. The response of Makrofol to fast neutrons is dependent on several factors. Based on the parameters which affect the track revealing, the formation of visible tracks was determined. For

  15. Monte Carlo simulation of mixed neutron-gamma radiation fields and dosimetry devices

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guoqing

    2011-12-22

    Monte Carlo methods based on random sampling are widely used in different fields for the capability of solving problems with a large number of coupled degrees of freedom. In this work, Monte Carlos methods are successfully applied for the simulation of the mixed neutron-gamma field in an interim storage facility and neutron dosimeters of different types. Details are discussed in two parts: In the first part, the method of simulating an interim storage facility loaded with CASTORs is presented. The size of a CASTOR is rather large (several meters) and the CASTOR wall is very thick (tens of centimeters). Obtaining the results of dose rates outside a CASTOR with reasonable errors costs usually hours or even days. For the simulation of a large amount of CASTORs in an interim storage facility, it needs weeks or even months to finish a calculation. Variance reduction techniques were used to reduce the calculation time and to achieve reasonable relative errors. Source clones were applied to avoid unnecessary repeated calculations. In addition, the simulations were performed on a cluster system. With the calculation techniques discussed above, the efficiencies of calculations can be improved evidently. In the second part, the methods of simulating the response of neutron dosimeters are presented. An Alnor albedo dosimeter was modelled in MCNP, and it has been simulated in the facility to calculate the calibration factor to get the evaluated response to a Cf-252 source. The angular response of Makrofol detectors to fast neutrons has also been investigated. As a kind of SSNTD, Makrofol can detect fast neutrons by recording the neutron induced heavy charged recoils. To obtain the information of charged recoils, general-purpose Monte Carlo codes were used for transporting incident neutrons. The response of Makrofol to fast neutrons is dependent on several factors. Based on the parameters which affect the track revealing, the formation of visible tracks was determined. For

  16. Neutron field characterization and dosimetry at the TRIUMF proton therapy facility

    International Nuclear Information System (INIS)

    Mukherjee, B.

    2002-01-01

    Full text: In 1972 the 500 MeV H' Cyclotron of the TRIUMF (Tri University Meson Factory) located in Vancouver, Canada became operational. Beside Meson Physics, high-energy protons of various energy and beam current levels from the TRIUMF Cyclotron are used for scientific research and biomedical applications. Recently, a 500 MeV proton beam from the cyclotron was used as the booster beam for the radioactive ion beam facility, ISAC (Isotope Separator Accelerator) and a second beam as primary irradiation source for the Proton Irradiation Facility (PIF). The major commercial applications of the PIF are the provision of high-energy proton beams for radiation hardness testing of electronic components used in space applications (NASA) and proton therapy of ocular tumors (British Columbia Proton Therapy Facility). The PIF vault was constructed within the main accelerator hall of the TRIUMF using stacks of large concrete blocks. An intense field of fast neutrons is produced during the interaction of high-energy proton beam with target materials, such as, beam stops, collimators and beam energy degraders. The leakage of such neutrons due to insufficient radiological shielding or through the shielding discontinuities may constitute a major share of the personnel radiation exposure of the radiation workers. The neutron energy distribution and dose equivalent near a lead beam stopper bombarded with 116 MeV and 65 MeV collimated proton beams at the Ocular Tumor irradiation facility were evaluated using a Bonner-Sphere Spectrometer and a REM counter respectively. The results were utilized to investigate efficacy of the existing radiological shielding of the PIF. This paper highlights experimental methods to analyze the high-energy accelerator produced neutron beam and basic guideline for the radiological shielding designs of irradiation vault of Proton Therapy facilities

  17. Dosimetry and shielding

    International Nuclear Information System (INIS)

    Farinelli, U.

    1977-01-01

    Today, reactor dosimetry and shielding have wide areas of overlap as concerns both problems and methods. Increased interchange of results and know-how would benefit both. The areas of common interest include calculational methods, sensitivity studies, theoretical and experimental benchmarks, cross sections and other nuclear data, multigroup libraries and procedures for their adjustment, experimental techniques and damage functions. This paper reviews the state-of-the-art and the latest development in each of these areas as far as shielding is concerned, and suggests a number of interactions that could be profitable for reactor dosimetry. Among them, re-evaluation of the potentialities of calculational methods (in view of the recent developments) in predicting radiation environments of interest; the application of sensitivity analysis to dosimetry problems; a common effort in the field of theoretical benchmarks; the use of the shielding one-material propagation experiments as reference spectra for detector cross sections; common standardization of the detector nuclear data used in both fields; the setting up of a common (or compatible) multigroup structure and library applicable to shielding, dosimetry and core physics; the exchange of information and experience in the fields of cross section errors, correlations and adjustment; and the intercomparison of experimental techniques

  18. Dosimetry of an accident in mixed field (neutrons, photons) using the spectrometry by electronic paramagnetic resonance(EPR); Dosimetrie d'accident en champ mixte (neutrons, photons) utilisant la spectrometrie par resonance paramagnetique electronique (RPE)

    Energy Technology Data Exchange (ETDEWEB)

    Herve, M.L

    2006-03-15

    In a radiological accident, the assessment of the dose received by the victim is relevant information for the therapeutic strategy. Two complementary dosimetric techniques based on physical means are used in routine practice in the laboratory: EPR spectroscopy performed on materials removed from the victim or gathered from the vicinity of the victim and Monte Carlo calculations. EPR dosimetry, has been used successfully several times in cases of photon or electron overexposures. Accidental exposure may also occur with a neutron component. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials (ascorbic acid, sorbitol, glucose, galactose, fructose, mannose, lactose and sucrose). The influence of irradiation parameters (dose, dose rate, photon energy) and of environmental parameters (temperature of heating, light exposure) on the EPR signal amplitude was studied. To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of experimental reactors with different neutron to photon ratios. The relative neutron sensitivity was found to range from 10% to 43% according to the materials. Prior knowledge of the ratio between the dose in samples measured by EPR spectrometry and organ or whole body dose obtained by calculations previously performed for these different configurations, makes it possible to give a first estimation of the dose received by the victim in a short delay. The second aim of this work is to provide data relevant for a quick assessment of the dose distribution in case of accidental overexposure based on EPR measurements performed on one or several points of the body. The study consists in determining by calculation the relation between the dose to the organs and whole body and the dose to specific points of the body, like teeth, bones or samples located in the pockets of victim clothes, for different external exposures corresponding

  19. Radiation dosimetry in radiotherapy with internal emitters

    International Nuclear Information System (INIS)

    Stabin, Michael G.

    1997-01-01

    Full text. Radiation dosimetry radionuclides are currently being labeled to various biological agents used in internal emitter radiotherapy. This talk will review the various technologies and types of radiolabel in current use, with focus on the characterization of the radiation dose to the various important tissues of the body. Methods for obtaining data, developing kinetic models, and calculating radiation doses will be reviewed. Monoclonal antibodies are currently being labeled with both alpha and beta emitting radionuclides in attempts to find effective agents against cancer. Several radionuclides are also being used as bone pain palliation agents. These agents must be studied in clinical trials to determine the biokinetics and radiation dosimetry prior to approval for general use. In such studies, it is important to ensure the collection of the appropriate kinds of data and to collect the data at appropriate time intervals. The uptake and retention of activity in all significant source organs and in excreta be measured periodically (with at least 2 data points phase of uptake or clearance). Then, correct dosimetry methods must be applied - the best available methods for characterizing the radionuclide kinetic and for estimating the dosimetry in the various organs of the body especially the marrow, should be used. Attempts are also under way to develop methods for estimating true patient-specific dosimetry. Cellular and animal studies are also. Valuable in evaluating the efficacy of the agents in shrinking or eliminating tumors; some results from such studies will also be discussed. The estimation of radiation doses to patients in therapy with internal emitters involves several complex phases of analysis. Careful attention to detail and the use of the best available methods are essential to the protection of the patient and a successful outcome

  20. Foundations of ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Denisenko, O.N.; Pereslegin, I.A.

    1985-01-01

    Foundations of dosimetry in application to radiotherapy are presented. General characteristics of ionizing radiations and main characteristics of ionizing radiation sources, mostly used in radiotherapy, are given. Values and units for measuring ionizing radiation (activity of a radioactive substance, absorbed dose, exposure dose, integral dose and dose equivalent are considered. Different methods and instruments for ionizing radiation dosimetry are discussed. The attention is paid to the foundations of clinical dosimetry (representation of anatomo-topographic information, choice of radiation conditions, realization of radiation methods, corrections for a configuration and inhomogeneity of a patient's body, account of biological factors of radiation effects, instruments of dose field formation, control of irradiation procedure chosen)

  1. Stable tracer investigations in humans for assessing the biokinetics of ruthenium and zirconium radionuclides

    International Nuclear Information System (INIS)

    Veronese, I.; Cantone, M.C.; Giussani, A.; Maggioni, T.; Birattari, C.; Bondardi, M.; Groppi, F.; Garlaschelli, I.; Werner, E.; Roth, P.; Hoellriegl, V.; Louvat, P.; Felgenhauer, N.; Zilker, Th.

    2003-01-01

    The interest in the biokinetics of ruthenium and zirconium in humans is justified by the potential radiological risk represented by their radionuclides. Only a few data related to the biokinetics of ruthenium and zirconium in humans are available and, accordingly, the biokinetic models currently recommended by the ICRP for these elements are mainly based on data from animal experiments. The use of stable isotopes as tracers, coupled with a proper analytical technique (nuclear activation analysis with protons) for their determination in biological samples, represents an ethically acceptable methodology for biokinetic investigations, being free from any radiation risk for the volunteer subjects. In this work, the results obtained in eight biokinetic investigations for ruthenium, conducted on a total of three healthy volunteers, and six for zirconium, performed on a total of three subjects, are presented and compared to the predictions of the ICRP models. (author)

  2. Software for biokinetic modeling of the radiopharmaceuticals used in PET

    International Nuclear Information System (INIS)

    Cordeiro, Leanderson P.; Vieira, Igor F.; Lima, Fernando R.A. de; Vieira, Jose W.

    2013-01-01

    In this work will be presented the current state of software in development to estimate the dose from PET images. Will be given the main biokinetic models used in PET, as well as the general features of a tool in development, whose current features allow quantitative analysis of compartmental models. Further, the tool allows display images 2D PET (in DICOM format) and quantify the intensity map of regions of interest in counts per second coincidence events. The next step is to insert in the same tool to estimate the activity concentration for ROI and estimate dose from PET images static and / or dynamic

  3. Biokinetic models for the metabolism of uranium: an overview

    International Nuclear Information System (INIS)

    Bertelli, Luiz; Lipsztein, Joyce L.; Melo, Dunstana R.; Puerta, Anselmo; Wrenn, McDonald E.

    1997-01-01

    This work reviews the main experiments involving uranium injection and inhalation into several animal species and those associated with humans as well. The literature was carefully selected to involve the uranium intake, distribution and excretion in humans and mammals. The available biokinetic models for the uranium metabolism, proposed by ICRP in Publications 2, 30 and 69, were shortly described and tested against the data. Human data which incorporates measurements of urine, autopsy and biopsy samples were also used completing the review of models associated with the systemic part. (author). 21 refs., 4 figs

  4. Polynomial Chaos decomposition applied to stochastic dosimetry: study of the influence of the magnetic field orientation on the pregnant woman exposure at 50 Hz.

    Science.gov (United States)

    Liorni, I; Parazzini, M; Fiocchi, S; Guadagnin, V; Ravazzani, P

    2014-01-01

    Polynomial Chaos (PC) is a decomposition method used to build a meta-model, which approximates the unknown response of a model. In this paper the PC method is applied to the stochastic dosimetry to assess the variability of human exposure due to the change of the orientation of the B-field vector respect to the human body. In detail, the analysis of the pregnant woman exposure at 7 months of gestational age is carried out, to build-up a statistical meta-model of the induced electric field for each fetal tissue and in the fetal whole-body by means of the PC expansion as a function of the B-field orientation, considering a uniform exposure at 50 Hz.

  5. Dosimetry of high energy radiation

    CERN Document Server

    Sahare, P D

    2018-01-01

    High energy radiation is hazardous to living beings and a threat to mankind. The correct estimation of the high energy radiation is a must and a single technique may not be very successful. The process of estimating the dose (the absorbed energy that could cause damages) is called dosimetry. This book covers the basic technical knowledge in the field of radiation dosimetry. It also makes readers aware of the dangers and hazards of high energy radiation.

  6. Verification of dosimetry cross sections above 10 MeV based on measurement of activation reaction rates in fission neutron field

    International Nuclear Information System (INIS)

    Odano, Naoteru; Miura, Toshimasa; Yamaji, Akio.

    1996-01-01

    To validate the dosimetry cross sections in fast neutron energy range, activation reaction rates were measured for 5 types of dosimetry cross sections which have sensitivity in the energy rage above 10 MeV utilizing JRR-4 reactor of JAERI. The measured reaction rates were compared with the calculations reaction rates by a continuous energy monte carlo code MVP. The calculated reaction rates were based on two dosimetry files, JENDL Dosimetry File and IRDF-90.2. (author)

  7. Dosimetry of Radiopharmaceuticals for Diagnostic and Therapeutic Nuclear Medicine

    International Nuclear Information System (INIS)

    Smart, Richard

    2011-01-01

    A standard formalism for radionuclide internal radiation dosimetry was developed in the 1960s and continues to be refined today. Early work was based on a mathematical phantom but this is being replaced by phantoms developed from whole-body CT scans to give more realistic dose estimates. The largest contributors to the uncertainties in these dose estimates are the errors associated with in vivo activity quantitation, the variability of the biokinetics between patients and the limited information that can be obtained on these kinetics in individual patients. Despite these limitations, pre-treatment patient-specific dosimetry is being increasing used, particularly to limit the toxicity to non-target organs such as the bone marrow.

  8. Techniques for radiation measurements: Micro-dosimetry and dosimetry

    International Nuclear Information System (INIS)

    Waker, A. J.

    2006-01-01

    Experimental Micro-dosimetry is concerned with the determination of radiation quality and how this can be specified in terms of the distribution of energy deposition arising from the interaction of a radiation field with a particular target site. This paper discusses various techniques that have been developed to measure radiation energy deposition over the three orders of magnitude of site-size; nano-meter, micrometer and millimetre, which radiation biology suggests is required to fully account for radiation quality. Inevitably, much of the discussion will concern the use of tissue-equivalent proportional counters and variants of this device, but other technologies that have been studied, or are under development, for their potential in experimental Micro-dosimetry are also covered. Through an examination of some of the quantities used in radiation metrology and dosimetry the natural link with Micro-dosimetric techniques will be shown and the particular benefits of using Micro-dosimetric methods for dosimetry illustrated. (authors)

  9. A biokinetic study of {sup 209}Po in man

    Energy Technology Data Exchange (ETDEWEB)

    Henricsson, C.F.; Ranebo, Y. [Department of Medical Radiation Physics, Clinical Sciences in Lund, Lund University, Skane University Hospital in Lund (Sweden); Hansson, M. [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Raeaef, C.L., E-mail: Christopher.Raaf@med.lu.se [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Holm, E. [Norwegian Radiation Protection Authority, Osteras (Norway)

    2012-10-15

    Five adult volunteers participated in a biokinetic study of radioactive polonium. Portions of about 10 Bq of {sup 209}Po were orally administrated to four of the volunteers in a single ingestion. The fifth volunteer ingested a daily amount of 53 mBq of 209Po for 243 d to study the time to achieve equilibrium between intake and excretion for protracted intakes. For the subjects ingesting single intakes of {sup 209}Po complete sampling of urine and feces was subsequently collected the first few days upon the ingestion. The samples were processed with radiochemical extraction and analyzed with alpha spectrometry. In the study, the maximum daily excretion rates in feces were 18-50% of the ingested activity, observed within 3 d after intake. Regarding the urine excretion, the daily excretion peaked, on average, at 0.15-1% of the ingested activity within two days upon intake. These results indicate an average gastro-intestinal uptake fraction of 0.46 {+-} 0.08, which agrees well with earlier biokinetic studies of polonium in man. -- Highlights: Black-Right-Pointing-Pointer Human metabolism of an oral intake of polonium. Black-Right-Pointing-Pointer 4 individuals were administrated about 10 Bq polonium-209. Black-Right-Pointing-Pointer Gastro-intestinal uptake fraction, if orally administrated polonium-209 was investigated. Black-Right-Pointing-Pointer The biological half-time of polonium in human body was studied.

  10. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1981-01-01

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments

  11. Sci-Sat AM: Radiation Dosimetry and Practical Therapy Solutions - 01: Optimization of an organic field effect transistor for radiation dosimetry measurements

    Energy Technology Data Exchange (ETDEWEB)

    Syme, Alasdair [Dept of Radiation Oncology, Dalhousie University, QEII Health Sciences Centre (Canada)

    2016-08-15

    Purpose: To use Monte Carlo simulations to optimize the design of an organic field effect transistor (OFET) to maximize water-equivalence across the diagnostic and therapeutic photon energy ranges. Methods: DOSXYZnrc was used to simulate transport of mono-energetic photon beams through OFETs. Dose was scored in the dielectric region of devices and used for evaluating the response of the device relative to water. Two designs were considered: 1. a bottom-gate device on a substrate of polyethylene terephthalate (PET) with an aluminum gate, a dielectric layer of either PMMA or CYTOP (a fluorocarbon) and an organic semiconductor (pentacene). 2. a symmetric bilayer design was employed in which two polymer layers (PET and CYTOP) were deposited both below the gate and above the semiconductor to improve water-equivalence and reduce directional dependence. The relative thickness of the layers was optimized to maximize water-equivalence. Results: Without the bilayer, water-equivalence was diminished relative to OFETs with the symmetric bilayer at low photon energies (below 80 keV). The bilayer’s composition was designed to have one layer with an effective atomic number larger than that of water and the other with an effective atomic number lower than that of water. For the particular materials used in this study, a PET layer 0.1mm thick coupled with a CYTOP layer of 900 nm provided a device with a water-equivalence within 3% between 20 keV and 5 MeV. Conclusions: organic electronic devices hold tremendous potential as water-equivalent dosimeters that could be used in a wide range of applications without recalibration.

  12. SU-F-T-367: Using PRIMO, a PENELOPE-Based Software, to Improve the Small Field Dosimetry of Linear Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Benmakhlouf, H; Andreo, P [Department of Medical Physics, Karolinska University Hospital (Sweden); Brualla, L [NCTeam, Strahlenklinik, Universitatsklinikum Essen (Germany); Sempau, J [Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya (Spain)

    2016-06-15

    Purpose: To calculate output correction factors for Varian Clinac 2100iX beams for seven small field detectors and use the values to determine the small field output factors for the linacs at Karolinska university hospital. Methods: Phase space files (psf) for square fields between 0.25cm and 10cm were calculated using the PENELOPE-based PRIMO software. The linac MC-model was tuned by comparing PRIMO-estimated and experimentally determined depth doses and lateral dose-profiles for 40cmx40cm fields. The calculated psf were used as radiation sources to calculate the correction factors of IBA and PTW detectors with the code penEasy/PENELOPE. Results: The optimal tuning parameters of the MClinac model in PRIMO were 5.4 MeV incident electron energy and zero energy spread, focal spot size and beam divergence. Correction factors obtained for the liquid ion chamber (PTW-T31018) are within 1% down to 0.5 cm fields. For unshielded diodes (IBA-EFD, IBA-SFD, PTW-T60017 and PTW-T60018) the corrections are up to 2% at intermediate fields (>1cm side), becoming down to −11% for fields smaller than 1cm. The shielded diode (IBA-PFD and PTW-T60016) corrections vary with field size from 0 to −4%. Volume averaging effects are found for most detectors in the presence of 0.25cm fields. Conclusion: Good agreement was found between correction factors based on PRIMO-generated psf and those from other publications. The calculated factors will be implemented in output factor measurements (using several detectors) in the clinic. PRIMO is a userfriendly general code capable of generating small field psf and can be used without having to code own linac geometries. It can therefore be used to improve the clinical dosimetry, especially in the commissioning of linear accelerators. Important dosimetry data, such as dose-profiles and output factors can be determined more accurately for a specific machine, geometry and setup by using PRIMO and having a MC-model of the detector used.

  13. The effect of independent collimator misalignment on the dosimetry of abutted half-beam blocked fields for the treatment of head and neck cancer

    International Nuclear Information System (INIS)

    Rosenthal, D.I.; McDonough, J.; Kassaee, A.

    1998-01-01

    Background and purpose: Independent collimation conveniently allows for the junctioning of abutting fields with non-diverging beam edges. When this technique is used at the junction of multiple fields, e.g. lateral and low anterior fields in three-field head and neck set-ups, there should be a dosimetric match with no overdose or underdose at the matchline. We set out to evaluate the actual dosimetry at the central match plane. Materials and methods: Independent jaws were used to mimic two half-beam blocked fields abutting at the central axis. X-Ray verification film was exposed in a water-equivalent phantom and the dose at the matchline was evaluated with laser densitometry. Collimators were then programmed to force a gap or overlap of the radiation fields to evaluate the effect of jaw misalignment within the tolerance of the manufacturer's specification. Diode measurements of the field edges were also performed. Four beam energies from four different linear accelerators were evaluated. Results: Small systematic inhomogeneities were found along the matchline in all linear accelerators tested. The maximum dose on the central axis varied linearly with small programmed jaw misalignments. For a gap or overlap of 2 mm between the jaws, the matchline dose increased or decreased by 30-40%. The region of overdose or underdose around the matchline is 3-4 mm wide. The discrepancy between the width of jaw separation and the width of the region of altered dose is explained by a penumbra effect.Conclusion: We recommend that independent jaw alignment be evaluated routinely and provide a simple method to estimate dose inhomogeneity at the match plane. If there is a field gap or overlap resulting in a clinically significant change in dosimetry, jaw misalignment should be corrected. If it cannot be corrected, part of the benefit of asymmetric collimation is lost and other methods of field junctioning may have to be considered. We routinely use a small block over the spinal cord at

  14. Hematological dosimetry

    International Nuclear Information System (INIS)

    Fluery-Herard, A.

    1991-01-01

    The principles of hematological dosimetry after acute or protracted whole-body irradiation are reviewed. In both cases, over-exposure is never homogeneous and the clinical consequences, viz medullary aplasia, are directly associated with the mean absorbed dose and the seriousness and location of the overexposure. The main hematological data required to assess the seriousness of exposure are the following: repeated blood analysis, blood precursor cultures, as indicators of whole-body exposure; bone marrow puncture, medullary precursor cultures and medullary scintigraphy as indicators of the importance of a local over-exposure and capacity for spontaneous repair. These paraclinical investigations, which are essential for diagnosis and dosimetry, are also used for surveillance and for the main therapeutic issues [fr

  15. Performance analysis of numeric solutions applied to biokinetics of radionuclides; Analise de desempenho de solucoes numericas aplicadas a biocinetica de radionuclideos

    Energy Technology Data Exchange (ETDEWEB)

    Mingatos, Danielle dos Santos; Bevilacqua, Joyce da Silva, E-mail: dani@ime.usp.br, E-mail: joyce@ime.usp.br [Universidade de Sao Paulo (IME/USP), SP (Brazil). Instituto de Matematica e Estatistica; Todo, Alberto Saburo; Rodrigues Junior, Orlando, E-mail: astodo@ipen.br, E-mail: rodrijr@ipen.br [Instituto de Pesquisas Energeticas Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Biokinetics models for radionuclides applied to dosimetry problems are constantly reviewed by ICRP. The radionuclide trajectory could be represented by compartmental models, assuming constant transfer rates between compartments. A better understanding of physiological or biochemical phenomena, improve the comprehension of radionuclide behavior in the human body and, in general, more complex compartmental models are proposed, increasing the difficulty of obtaining the analytical solution for the system of first order differential equations. Even with constant transfer rates numerical solutions must be carefully implemented because of almost singular characteristic of the matrix of coefficients. In this work we compare numerical methods with different strategies for ICRP-78 models for Thorium-228 and Uranium-234. The impact of uncertainty in the parameters of the equations is also estimated for local and global truncation errors. (author)

  16. Thermo-luminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Reither, M; Schorn, B; Schneider, E

    1981-01-01

    The development of paediatric radiology which began in the late 195O's has been characterised by the need to limit the dose of ionising radiation to which the child is subjected. The aim has been to keep radiation exposure as low as possible by the introduction of suitable techniques and by the development of new methods. It is therefore surprising that studies in dosimetry in the paediaytric age range have only been carried out in recent years. One reason for this may have been the fact that a suitable technique of measurement was not available at the time. The introduction of solid state dosimetry based on thermo-luminescence, first into radiotherapy (1968) and subsequently into radiodiagnosis, has made it possible to abandon the previously widely used ionisation chamber. The purpose of the present paper is to indicate the suitability of this form of dose measurement for paediatric radiological purposes and to stimulate its application in this field.

  17. Legal aspects of dosimetry

    International Nuclear Information System (INIS)

    Pomarola, H.

    1976-01-01

    The use of ionizing radiations is regulated in France in all fields of application. The main principles governing inspection activities in the food industry are outlined. Conventional preservation methods are mentioned, after which a discussion is devoted to the preservation of food products by irradiation treatment and the increasing importance given to this technique. Consumer protection automatically implies the obligatory use of dosimetry by inspection organisms if the irradiated merchandise is likely to serve for human or animal consumption. Irradiation treatment permits are granted in a context of specific statutory texts mentioned here. Supervision is constant, but always both realistic and flexible. Each aspect of this treatment is discussed in maximum detail if not quite exhaustively, with special emphasis on dosimetry as an indispensable safety factor [fr

  18. Transuranic biokinetic parameters for marine invertebrates--a review.

    Science.gov (United States)

    Ryan, T P

    2002-04-01

    A catalogue of biokinetic parameters for the transuranic elements plutonium, americium, curium, neptunium, and californium in marine invertebrates is presented. The parameters considered are: the seawater-animal concentration factor (CF); the sediment-animal concentration ratio (CR); transuranic assimilation efficiency; transuranic tissue distribution and transuranic elimination rates. With respect to the seawater-animal CF, authors differ considerably on how they define this parameter and a seven-point reporting system is suggested. Transuranic uptake from sediment by animals is characterised by low CRs. The assimilation efficiencies of transuranic elements in marine invertebrates are high compared to vertebrates and mammals in general and the distribution of transuranics within the body tissue of an animal is dependent on the uptake path. The elimination of transuranics from most species examined conformed to a standard biphasic exponential model though some examples with three elimination phases were identified.

  19. The biokinetics and radiotoxicology of curium: A comparison with americium

    Energy Technology Data Exchange (ETDEWEB)

    Menetrier, F. [CEA, Fontenay-aux-Roses (France); Taylor, D.M. [School of Chemistry, Cardiff University, Cardiff CF10 3AT (United Kingdom)], E-mail: davtay@btinternet.com; Comte, A. [CEA, Fontenay-aux-Roses (France)

    2008-05-15

    The human and animal data on the biokinetics of {sup 242}Cm and {sup 244}Cm are reviewed and shown to be very similar to those for {sup 241}Am. Liver and skeleton are the main organs of deposition and the retention of curium in the skeleton is very prolonged in all the species examined. Retention of both curium and americium in the liver appears to be species-dependent, being relatively rapidly removed from the liver of rats, and probably humans, but being tenaciously retained in dogs and some other species. The radiotoxicity of curium is also reviewed and it is shown that, as with {sup 241}Am, lung and bone tumour induction are the major hazards from inhaled and systemically deposited {sup 244}Cm. The use of chelating agents for the treatment of accidental contamination of the human body with {sup 242,244}Cm is also discussed.

  20. A biokinetic and dosimetric model for the metabolism of uranium

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Bertelli, L.; Durbin, P.W.; Eckerman, K.F.; Lipsztein, J.L.; Singh, N.P.

    1995-10-01

    Experiments involving injection and inhalation of uranium compounds into several animal species as well as those associated with humans are described and analyzed. A revised biokinetic and dosimetric model for the metabolism of uranium suitable for bioassay procedures is proposed. The model consists of a systematic part coupled to a model of the respiratory tract. The model has been tested against human data which incorporates in vivo measurements over the chest and measurements of urine, feces, and autopsy and biopsy samples.In particular the lung model of the International Commission on Radiological Protection, Publication 30 ( ICRP-30 ), has been modified in order to provide a model which more nearly predicts urinary excretion in accord with the experiences in humans and animals. We have also tested the data against the new ICRP (LUDEP) lung model. (author). 55 refs., 14 tabs., 33 figs

  1. The effect of isotope on the dosimetry of inhaled plutonium oxide

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Griffith, W.C.

    1991-01-01

    Results of experimental studies in which animals inhaled 238 PuO 2 or 239 PuO 2 aerosols have shown that the biokinetics and associated radiation dose patterns for these two isotopes differ significantly due to differences in in-vivo solubility caused by the 260-fold difference in specific activity between 238 PuO 2 and 239 PuO 2 . We have adapted a biokinetics and dosimetry model derived from results of the ITRI dog studies to humans and have calculated dose commitments and annual limits on intake (ALI) for both Pu isotopes. Our results show that the ALI calculated in this study is one-third that for class Y 238 Pu from ICRP 30, and one-half or equal to that for class Y 239 Pu, depending on how activity in the thoracic lymph nodes is treated dosimetrically

  2. The Effect of Body Size in Mercury Accumulation Biokinetic of Cockle Shell (Anadara Granosa)

    International Nuclear Information System (INIS)

    Wahyu Retno Prihatiningsih

    2007-01-01

    Accumulation of mercury biokinetic in cockle shell (Anadara granosa) through water pathway has been investigated under laboratory condition. The objective of research is to find the effect of body size in mercury biokinetic of Anadara granosa and to find bioindicator based on biokinetic parameter. The research shows that body size of Anadara granosa give an effect to concentration factor and could barrier mercury contaminant. Concentration factor for size 1.9, 2.5 and 3.9 cm of biota moving high and reach steady state condition after 24 days. Concentration factor of Anadara granosa in size 1.9, 2.5 and 3.9 is 0.1476, 0.1645 and 0.2573 day. Based on mechanism of mercury biokinetic process, it was proof that Anadara granosa is an ideal invertebrate for bioindicator. (author)

  3. A case of accidental intake of Molybdenum Radionuclides: analysis of data with a revised biokinetic model

    International Nuclear Information System (INIS)

    Giussani, A.; Cantone, M.C.; Tavola, F.; Lopez, M.A.; Navarro, T.

    2002-01-01

    In recent years, a series of investigations on the biokinetics of molybdenum in humans, conducted using stable isotopes of Mo as tracers, has provided valuable experimental data about the dynamics of relevant processes such as the uptake from the gut walls, the clearance from the systemic circulation and the elimination pathways. The results of these studies are in good agreement with the findings of a group of nutritionist who also performed biokinetic studies with stable tracers. All measurements show several deviations from the predictions of the current ICRP model. On the basis of these data, a preliminary revision of the biokinetic model for Mo was presented. The modified model was thus used as a starting point for a new series of biokinetic investigations, aimed at a better definition of some of its features. In a total of 54 studies conducted in 15 volunteers, the influence of the mass and of the chemical form on intestinal absorption, internal kinetics and urinary excretion was investigated

  4. A generic biokinetic model for predicting the behaviour of the lanthanide elements in the human body

    International Nuclear Information System (INIS)

    Taylor, D.M.; Leggett, R.W.

    2003-01-01

    Information on the biokinetics of the 15 elements of the lanthanide series, 57 La to 71 Lu, is too sparse to permit individual development of meaningful biokinetic models to describe the behaviour of each of the elements in humans. The lanthanides show a regular gradation in chemical properties across the series, and animal studies indicate that this is reflected in regular differences in their deposition in tissues such as the liver and skeleton. These regular differences in chemical and biological behaviour have been utilised to construct a generic lanthanide biokinetic model and to define element-specific parameters for each element in the series. This report describes the use of the available biokinetic data for humans and animals to derive the parameters for each of the elements. (author)

  5. Biokinetic study of 131I following ablation dose administration

    International Nuclear Information System (INIS)

    Nascimento, A.C.H.; Lipsztein, J.L.; Lucena, E.A.; Dantas, B.M.; Rebelo, A.M.O.; Mello, R.C.

    2002-01-01

    Aim: The aim of this investigation is to study biokinetics from internally 131 I deposited for thyroid cancer patients during radioiodine therapy (2 to 3 days), after ablation dose administration (3.7 GBq). These data will help in the elaboration of a metabolic model, which will permit absorbed dose assessment for this specific case, since the biokinetic models for iodine available in scientific literature can not be applied to thyroidectomized patient's studies. Material and Methods: Four females patients, between 22 and 50 years old, without metastases, between 1.9 to 6% of remnant thyroid tissue uptake, agreed to contribute to this study. For the in vivo bioassay, periodical measurements were performed along internment time (2 to 3 days), just after Na 131 I dose administration (3.7 GBq). For this, we used the counting system for Nuclear Medicine model 13S002, IEN/CNEN- Brazil, which was adapted with lead filters, in order to allow the work with high rate counting. The measurements were performed in two geometries: thyroid region and thigh. Results: For each patient, we have done approximately 26 measurements for both geometries, starting at the first hour following dose administration until the release from hospital of patient. The results of counting rate (cps) were plotted against time (h). The measurements suggest a relation between remnant thyroid tissue uptake values and the time where counting rates start decreasing. In addition, it was observed a correlation between remnant thyroid tissue radioactive burdens and the circulating iodine through time. Conclusion: It is necessary to follow-up a greater number of patients aiming to confirm the observed correlations and with a greater number of measurements during the first 24 hours, in other to delimit the time range of increasing and decreasing counting rate

  6. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Soares, Christopher G.

    2006-01-01

    The object of this paper is to give a new user some practical information on the use of radiochromic films for medical applications. While various aspects of radiochromic film dosimetry for medical applications have been covered in some detail in several other excellent review articles which have appeared in the last few years [Niroomand-Rad, A., Blackwell, C.R., Coursey, B.M., Gall, K.P., McLaughlin, W.L., Meigooni, A.S., Nath, R., Rodgers, J.E., Soares, C.G., 1998. Radiochromic dosimetry: recommendations of the AAPM Radiation Therapy Committee Task Group 55. Med. Phys. 25, 2093-2115; Dempsey, J.F., Low, D.A., Mutic, S., Markman, J., Kirov, A.S., Nussbaum, G.H., Williamson, J.F., 2000. Validation of a precision radiochromic film dosimetry system for quantitative two-dimensional imaging of acute exposure dose distributions. Med. Phys. 27, 2462-2475; Butson, M.J., Yu, P.K.N., Cheung, T., Metcalfe, P., 2003. Radiochromic film for medical radiation dosimetry. Mater. Sci. Eng. R41, 61-120], it is the intent of the present author to present material from a more user-oriented and practical standpoint. That is, how the films work will be stressed much less than how to make the films work well. The strength of radiochromic films is most evident in applications where there is a very high dose gradient and relatively high absorbed dose rates. These conditions are associated with brachytherapy applications, measurement of small fields, and at the edges (penumbra regions) of larger fields

  7. Characterization of an electronic system for Image acquisition portal to open field dosimetry; Caracterizacao de um sistema eletronico de aquisicao de imagem portal para dosimetria em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Barbi, Gustavo L.; Oliveira, Harley F.; Bertucci, Edenyse C.; Amaral, Leonardo L.; Borges, Leandro F., E-mail: gustavobarbi@usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas. Centro de Ciencias das Imagens e Fisica Medica

    2012-08-15

    The objective was to characterize and enable an electronic portal imaging device (EPID) to use like a portal dosimetry device - PDI, in non-transit mode, without interposition of scattering between the beam and EPID for measurement to open fields. The images as well as the DICOM header data are extracted from software ImageJ and the information are used in the basic algorithm for converting pixel to dose. The linearity and reproducibility of response were analyzed, and the maximum deviation found of 2,3% to 800 monitor units (MU) for linearity and -0,9% for reproducibility of signal measured daily. A 512x512 matrix with a resolution of 0,8mm was established to restore the shape of beam from the image. The field size dependence was evaluated, by obtaining the ratio of total scattering of ionization chamber and EPID. Finally, a calibration factor of 28470.88{+-}170.73 pixel/cGy was established for the central area of the image. Comparative analyzes between the PDI, radiochromic film and array of ionization chambers (MatriXX) showed good agreement for fields greater then 5 x 5 cm{sup 2} to reestablishment of form field and dose, however, for fields between 3x3 cm{sup 2} and 5x5 cm{sup 2}, the agreement to shape of beam was best established by film. (author)

  8. French experience in the field of internal dosimetry assessment at a nuclear workplace. Methods and results on industrial uranium dioxide

    International Nuclear Information System (INIS)

    Ansoborlo, E.; Henge-Napoli, M.H.; Rannou, A.; Pihet, P.; Dewez, P.

    1995-01-01

    The implementation of the new ICRP recommendations and the diversity of industrial exposure materials make it necessary to modify our approach of assessing internal dosimetry. This paper describes a methodology developed to asses different parameters such as activity concentration and particle size distribution at the workplace; physico-chemical characteristics of industrial dust handled; and in vitro and in vivo solubility in order to determine the absorption rate blood. The determination of such specific parameters will lead to dose calculation in terms of committed effective Dose Per Unit of Intake (DPUI). Results obtained for an industrial uranium dioxide, UO 2 , at a French nuclear facility are presented. (author). 21 refs., 2 figs., 4 tabs

  9. Biokinetics of zinc oxide nanoparticles: toxicokinetics, biological fates, and protein interaction

    Directory of Open Access Journals (Sweden)

    Choi SJ

    2014-12-01

    Full Text Available Soo-Jin Choi,1 Jin-Ho Choy2 1Department of Food Science and Technology, Seoul Women's University, 2Center for Intelligent Nano Bio Materials (CINBM, Department of Bioinspired Science and Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, South Korea Abstract: Biokinetic studies of zinc oxide (ZnO nanoparticles involve systematic and quantitative analyses of absorption, distribution, metabolism, and excretion in plasma and tissues of whole animals after exposure. A full understanding of the biokinetics provides basic information about nanoparticle entry into systemic circulation, target organs of accumulation and toxicity, and elimination time, which is important for predicting the long-term toxic potential of nanoparticles. Biokinetic behaviors can be dependent on physicochemical properties, dissolution property in biological fluids, and nanoparticle–protein interaction. Moreover, the determination of biological fates of ZnO nanoparticles in the systemic circulation and tissues is critical in interpreting biokinetic behaviors and predicting toxicity potential as well as mechanism. This review focuses on physicochemical factors affecting the biokinetics of ZnO nanoparticles, in concert with understanding bioavailable fates and their interaction with proteins. Keywords: ZnO nanoparticles, biokinetics, distribution, excretion, fate, interaction

  10. Neutron Dosimetry

    International Nuclear Information System (INIS)

    Vanhavere, F.

    2001-01-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding

  11. Neutron Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Vanhavere, F

    2001-04-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding.

  12. Potential of discrete Gaussian edge feathering method for improving abutment dosimetry in eMLC-delivered segmented-field electron conformal therapy

    Energy Technology Data Exchange (ETDEWEB)

    Eley, John G.; Hogstrom, Kenneth R.; Matthews, Kenneth L.; Parker, Brent C.; Price, Michael J. [Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States) and Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States); Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, 202 Nicholson Hall, Tower Drive, Baton Rouge, Louisiana 70803-4001 (United States) and Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 (United States)

    2011-12-15

    Purpose: The purpose of this work was to investigate the potential of discrete Gaussian edge feathering of the higher energy electron fields for improving abutment dosimetry in the planning volume when using an electron multileaf collimator (eMLC) to deliver segmented-field electron conformal therapy (ECT). Methods: A discrete (five-step) Gaussian edge spread function was used to match dose penumbras of differing beam energies (6-20 MeV) at a specified depth in a water phantom. Software was developed to define the leaf eMLC positions of an eMLC that most closely fit each electron field shape. The effect of 1D edge feathering of the higher energy field on dose homogeneity was computed and measured for segmented-field ECT treatment plans for three 2D PTVs in a water phantom, i.e., depth from the water surface to the distal PTV surface varied as a function of the x-axis (parallel to leaf motion) and remained constant along the y-axis (perpendicular to leaf motion). Additionally, the effect of 2D edge feathering was computed and measured for one radially symmetric, 3D PTV in a water phantom, i.e., depth from the water surface to the distal PTV surface varied as a function of both axes. For the 3D PTV, the feathering scheme was evaluated for 0.1-1.0-cm leaf widths. Dose calculations were performed using the pencil beam dose algorithm in the Pinnacle{sup 3} treatment planning system. Dose verification measurements were made using a prototype eMLC (1-cm leaf width). Results: 1D discrete Gaussian edge feathering reduced the standard deviation of dose in the 2D PTVs by 34, 34, and 39%. In the 3D PTV, the broad leaf width (1 cm) of the eMLC hindered the 2D application of the feathering solution to the 3D PTV, and the standard deviation of dose increased by 10%. However, 2D discrete Gaussian edge feathering with simulated eMLC leaf widths of 0.1-0.5 cm reduced the standard deviation of dose in the 3D PTV by 33-28%, respectively. Conclusions: A five-step discrete Gaussian edge

  13. Fundamentals of Dosimetry. Chapter 3

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, E. M. [Universidade de São Paulo, São Paulo (Brazil)

    2014-09-15

    Determination of the energy imparted to matter by radiation is the subject of dosimetry. The energy deposited as radiation interacts with atoms of the material, as seen in the previous chapter. The imparted energy is responsible for the effects that radiation causes in matter, for instance, a rise in temperature, or chemical or physical changes in the material properties. Several of the changes produced in matter by radiation are proportional to the absorbed dose, giving rise to the possibility of using the material as the sensitive part of a dosimeter. Also, the biological effects of radiation depend on the absorbed dose. A set of quantities related to the radiation field is also defined within the scope of dosimetry. It will be shown in this chapter that, under special conditions, there are simple relations between dosimetric and field description quantities. Thus, the framework of dosimetry is the set of physical and operational quantities that are studied in this chapter.

  14. IMBA professional plus: internal dosimetry made simple

    International Nuclear Information System (INIS)

    Birchall, A.; Puncher, M.; Marsh, J.W.; Davis, K.; Bailey, M.R.; Peach, A.; James, A.C.; Jarvis, N.S.

    2005-01-01

    Full text: During 1997-1999, NRPB, in collaboration with British Nuclear Fuels plc (BNFL), and Westlakes Research Institute, produced IMBA (Integrated Modules for Bioassay Analysis), a suite of software modules that implement the current ICRP biokinetic and dosimetric models for estimation of intakes and doses. This was partly in response to new UK regulations that implemented the 1996 Euratom Directive, and partly in recognition of the advantages of a unified approach to estimating intakes and doses from bioassay measurements. The IMBA modules have gone through extensive quality assurance, and are now used for routine formal dose assessment by Approved Dosimetry Services throughout the UK. Over the past 5 years, NRPB has developed the IMBA modules further. In addition, several projects, sponsored by organizations both in the USA and in Canada, resulted in the development of customized user friendly interfaces (IMBA Expert TM 'editions'). These enable their users not only to use the standard ICRP models, but also to change many of the parameter values from their defaults, and also to apply sophisticated data handling techniques to internal dose calculations. These include fitting multiple data using the maximum likelihood method, multiple chronic and acute intakes, and multiple data types (urine, faeces, whole body etc.) simultaneously. These interfaces were improved further, as a result of user feedback, and a general off-the-shelf product, IMBA Professional, was developed and made available in January 2004. Following the success of IMBA Professional, a new and improved product IMBA Professional Plus is planned to be released in 2005. The new product is more powerful than its predecessor, six times faster, cheaper, and fully backward compatible with previous versions. It is envisaged that this package will continue to be developed as improved methods of analysis and biokinetic models become available. The aim of this paper is to describe the current capabilities

  15. Assessment of MicroDiamond PTW 60019 detector and its comparison with other detectors for relative dosimetry in small radiosurgery fields of the Leksell gamma knife perfexion

    International Nuclear Information System (INIS)

    Novotny, J. Jr.; Kozubikova, P.; Pastykova, V.; Pipek, J.; Bhatnagar, J. P.; Huq, M. S.; Veselsky, T.

    2014-01-01

    Measurement of relative output factors (ROF) for the Leksell Gamma Knife (LGK) is not a trivial task due to strict demands of an accurate set up and small size of measured radiosurgery fields. The purpose of this study was to perform an assessment of a new synthetic single crystal MicroDiamond PTW 60019 detector (volume 0.004 mm 3 ) for measurement of ROFs for 4 mm and 8 mm collimators for the LGK Perfexion. Small sensitive volume of this detector, near water equivalence and low energy dependence make it an attractive candidate for small field dosimetry. Results obtained in this study were compared with results measured by broad variety of different detectors and also Monte Carlo (MC) simulation. MicroDiamond detector connected to PTW UNIDOS electrometer was positioned in ELEKTA spherical phantom and pre-irradiated to dose of 5 Gy. Measurements were performed in two different detector positions: 1) parallel with table axis, 2) orthogonal to table axis. Electrometer timer of 1 min was used to measure subsequently signal from 16 mm, 8 mm and 4 mm beams. Altogether ten measurements were performed for each of three collimator sizes. Results from MicroDiamond were compared with those obtained from various types of detectors used in the past by authors for measurement of LGK ROFs. New synthetic single crystal MicroDiamond PTW 60019 detector appears to be a very promising detector for relative output factor measurements in very small radiosurgery fields. (authors)

  16. Testing and linearity calibration of films of phenol compounds exposed to thermal neutron field for EPR dosimetry.

    Science.gov (United States)

    Gallo, S; Panzeca, S; Longo, A; Altieri, S; Bentivoglio, A; Dondi, D; Marconi, R P; Protti, N; Zeffiro, A; Marrale, M

    2015-12-01

    This paper reports the preliminary results obtained by Electron Paramagnetic Resonance (EPR) measurements on films of IRGANOX® 1076 phenols with and without low content (5% by weight) of gadolinium oxide (Gd2O3) exposed in the thermal column of the Triga Mark II reactor of LENA (Laboratorio Energia Nucleare Applicata) of Pavia (Italy). Thanks to their size, the phenolic films here presented are good devices for the dosimetry of beams with high dose gradient and which require accurate knowledge of the precise dose delivered. The dependence of EPR signal as function of neutron dose was investigated in the fluence range between 10(11) cm(-2) and 10(14) cm(-2). Linearity of EPR response was found and the signal was compared with that of commercial alanine films. Our analysis showed that gadolinium oxide (5% by weight) can enhance the thermal neutron sensitivity more than 18 times. Irradiated dosimetric films of phenolic compound exhibited EPR signal fading of about 4% after 10 days from irradiation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Dose absorbed in adults and children thyroid due to the I{sup 123} using the dosimetry MIRD and Marinelli; Dosis absorbida en tiroides de adultos y ninos debido al I{sup 123} utilizando las dosimetrias MIRD y Marinelli

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, M.; Castillo, C.; Cabrera, C.; Sarachaga, R.; Castaneda, J. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru); Diaz, E., E-mail: marvva@hotmail.com [Universidade Federal do Rio Grande do Sul, Av. Paulo Gamma 110, Bairro Farropilhas, Porto Alegre, RS 90040-060 (Brazil)

    2014-08-15

    Using the dosimetry MIRD, and representation Cristy-Eckerman in the thyroid gland and organs of their bio-kinetics when I{sup 123} (Iodine) is used, the study demonstrates that the absorbed dose by the gland of an adult, children, and newly born, is their auto-dose, independent of the compartments number of their bio-kinetics. The dosimetric contributions of the organs of their bio-kinetics are insignificant. Their results are not significantly different to those obtained by the formalism MARINELLI (auto-dose) when it uses a sphere like glandular representation. In consequence, the kinetic model corresponding to the glandular representation decreases to a compartment, where the gland can also be represented like a sphere. (Author)

  18. Organ dosimetry

    International Nuclear Information System (INIS)

    Kaul, Dean C.; Egbert, Stephen D.; Otis, Mark D.; Kuhn, Thomas; Kerr, George D.; Eckerman, Keith F.; Cristy, Mark; Ryman, Jeffrey C.; Tang, Jabo S.; Maruyama, Takashi

    1987-01-01

    This chapter describes the technical approach, complicating factors, and sensitivities and uncertainties of calculations of doses to the organs of the A-bomb survivors. It is the object of the effort so described to provide data that enables the dosimetry system to determine the fluence, kerma, absorbed dose, and similar quantities in 14 organs and the fetus, specified as being of radiobiological interest. This object was accomplished through the use of adjoint Monte Carlo computations, which use a number of random particle histories to determine the relationship of incident neutrons and gamma rays to those transported to a target organ. The system uses these histories to correlate externally-incident energy- and angle-differential fluences with the fluence spectrum (energy differential only) within the target organ. In order for the system to work in the most efficient manner possible, two levels of data were provided. The first level, represented by approximately 6,000 random adjoint-particle histories, enables the computation of the fluence spectrum with sufficient precision to provide statistically reliable (± 6 %) mean doses within any given organ. With this limited history inventory, the system can be run rapidly for all survivors. Mean organ dose and dose uncertainty are obtainable in this mode. The second mode of operation enables the system to produce a good approximation to fluence spectrum within any organ or to produce the dose in each of an array of organ subvolumes. To be statistically reliable, this level of detail requires far more random histories, approximately 40,000 per organ. Thus, operation of the dosimetry system in this mode (i.e., with this data set) is intended to be on an as-needed, organ-specific basis, since the system run time is eight times that in the mean dose mode. (author)

  19. Accuracy Requirements in Medical Radiation Dosimetry

    International Nuclear Information System (INIS)

    Andreo, P.

    2011-01-01

    The need for adopting unambiguous terminology on 'accuracy in medical radiation dosimetry' which is consistent with international recommendations for metrology is emphasized. Uncertainties attainable, or the need for improving their estimates, are analysed for the fields of radiotherapy, diagnostic radiology and nuclear medicine dosimetry. This review centres on uncertainties related to the first step of the dosimetry chain in the three fields, which in all cases involves the use of a detector calibrated by a standards laboratory to determine absorbed dose, air kerma or activity under reference conditions in a clinical environment. (author)

  20. Internal dosimetry and control

    International Nuclear Information System (INIS)

    Rich, B.L.

    1990-05-01

    This internal dosimetry and control report provides guidance for EG ampersand G Idaho, Inc., field programs in detecting, evaluating, and controlling personnel exposure resulting from uptake of radionuclides by the body. Procedures specific to each program or facility are required to define the details of guidance from this report. Fundamental principles related to philosophy, policies, monitoring guidelines, and dose evaluation are discussed. Specific numerical guides and action levels are developed to guide the programs in evaluating the significance of specific analytical results. The requirement to thoroughly document the results and provide a formal technical base for each policy and/or practice is outlined and explained. 8 refs., 3 figs., 7 tabs

  1. Fast neutron dosimetry

    International Nuclear Information System (INIS)

    DeLuca, P.M. Jr.; Pearson, D.W.

    1992-01-01

    This progress report concentrates on two major areas of dosimetry research: measurement of fast neutron kerma factors for several elements for monochromatic and white spectrum neutron fields and determination of the response of thermoluminescent phosphors to various ultra-soft X-ray energies and beta-rays. Dr. Zhixin Zhou from the Shanghai Institute of Radiation Medicine, People's Republic of China brought with him special expertise in the fabrication and use of ultra-thin TLD materials. Such materials are not available in the USA. The rather unique properties of these materials were investigated during this grant period

  2. Beta calibration and dosimetry at IPEN

    International Nuclear Information System (INIS)

    Caldas, L.V.E.

    1983-01-01

    A commercial extrapolation chamber (PTW, Germany) was tested in different beta radiation fields and its properties investigated. Its usefullness for beta radiation calibration and dosimetry was demonstrated. (Author) [pt

  3. Individual dosimetry and calibration

    International Nuclear Information System (INIS)

    Otto, T.

    1997-01-01

    In 1996, the Dosimetry and Calibration Section was, as in previous years, mainly engaged in routine tasks: the distribution of over 6000 dosimeters (with a total of more than 10,000 films) every two months and the calibration of about 900 fixed and mobile instruments used in the radiation survey sections of RP group. These tasks were, thanks to an experienced team, well mastered. Special efforts had to be made in a number of areas to modernize the service or to keep it in line with new prescriptions. The Individual Dosimetry Service had to assure that CERN's contracting firms comply with the prescriptions in the Radiation Safety Manual (1996) that had been inspired by the Swiss Ordinance of 1994: Companies must file for authorizations with the Swiss Federal Office for Public Health requiring that in every company an 'Expert in Radiation Protection' be nominated and subsequently trained. CERN's Individual Dosimetry Service is accredited by the Swiss Federal Authorities and works closely together with other, similar services on a rigorous quality assurance programme. Within this framework, CERN was mandated to organize this year the annual Swiss 'Intercomparison of Dosimeters'. All ten accredited dosimetry services - among others those of the Paul Scherrer Institute (PSI) in Villigen and of the four Swiss nuclear power stations - sent dosimeters to CERN, where they were irradiated in CERN's calibration facility with precise photon doses. After return to their origin they were processed and evaluated. The results were communicated to CERN and were compared with the originally given doses. A report on the results was subsequently prepared and submitted to the Swiss 'Group of Experts on Personal Dosimetry'. Reference monitors for photon and neutron radiation were brought to standard laboratories to assure the traceability of CERN's calibration service to the fundamental quantities. For photon radiation, a set of ionization chambers was calibrated in the reference field

  4. Proposal of a new biokinetic model for niobium

    International Nuclear Information System (INIS)

    Oliveira, Roges

    2006-01-01

    There are two niobium isotopes generated in nuclear power plants: 95 Nb and 94 Nb. Workers and members of the public are subjects to intake these radionuclides in accident situation. For dose calculation purpose, it is very important to develop a model that describes in a more realistic way the kinetics of niobium inside of the human body. Presently the model adopted by ICRP (ICRP, 1989) is based on animal studies and describes the behavior of niobium in human being in a simple manner. The new model proposal describes the kinetics of the niobium from the intake into the blood until the excretion, doing this in a more realistic form and considering not only data from animals but data from human beings as well. For this objective, a workers group of a niobium extraction and processing industry exposed to stable niobium (93 Nb) in oxide insoluble form with associated uranium, was monitored for uranium and niobium determination in urinary and fecal excretion, by mass spectrometry. Based in the ratios of the niobium concentration in urinary and faecal excretion of this workers and animal data study, a new biokinetic model for niobium was proposed, with the followings modifications relative to ICRP model: a new compartment that represents muscular tissue; the fractions which are deposited into the compartment are modified; a third component in the retention equation of the bone tissue; introduction of recirculation between organs and blood. The new model was applied for a case of accidental intake and described adequately the experimental data

  5. Multigenerational cadmium acclimation and biokinetics in Daphnia magna

    International Nuclear Information System (INIS)

    Guan Rui; Wang Wenxiong

    2006-01-01

    A Cd exposure (3 μg L -1 ) experiment was conducted for six successive generations to investigate the responses to chronic Cd stress in Daphnia magna. We observed a biphasic accumulation of Cd in the six generations and suggested a similar pattern with respect to daphnids' tolerance. Cd assimilation efficiencies, daphnid growth, and reproduction corresponded to the changes of tolerance, which was partially accounted for by metallothionein induction. When maternally exposed neonates grew in Cd-free water for one or two generations, their growth, MT concentration and biokinetic parameters partially or totally recovered. The rapid recovery suggests the high potential for ecological restoration from Cd pollution. Our results indicate that the tolerance of sensitive D. magna clones to Cd was dependent on long-term or multigenerational exposure. The tolerance developed within the first several generations might not be maintained, and the animals may become even more sensitive to Cd stress in subsequent generations. - Tolerance of sensitive Daphnia magna clones to cadmium was dependent on long-term or multigenerational exposure

  6. The biokinetics of Rhuthenium and Zirconium radionuclides in humans studied with stable tracers

    International Nuclear Information System (INIS)

    Veronese, I.; Cantone, M.C.; Giussani, A.

    2002-01-01

    The assessment of the internal radiation dose delivered by radionuclides incorporated in the human body after accidental release into the environment requires the use of suitable biokinetic models. These models describe the absorption of radionuclides into the blood circulation, their distribution and retention in various organs and tissues, and the excretion routes. Biokinetic models are also employed for interpreting bioassay measurements in exposed subjects, like activity concentration measurements in body fluids (e.g. urine, blood), in order to estimate the incorporated amount of radioactive substances. The reliability of a biokinetic model is closely linked to the available experimental data used to develop the model itself. Biokinetic data for human subjects are available for most essential elements, as well as for some important non-essential elements such as caesium, lead, radium, uranium, americium and plutonium. For many other radionuclides, either very little or no information is available from human studies, and the respective models must be derived from other sources. These may include results from studies in animals, comparative data on the behaviour of similar radionuclides or chemical analogues in vitro. Biokinetic models developed from such a variety of data sources can be applied to humans only with a limited degree of confidence. The availability of data directly obtained on human subjects is therefore fundamental to set up more reliable and realistic models. Ruthenium and zirconium are among the elements characterised by a serious lack of reliable data in humans

  7. Advances in biomedical dosimetry

    International Nuclear Information System (INIS)

    1981-01-01

    Full text: Radiation dosimetry, the accurate determination of the absorbed dose within an irradiated body or a piece of material, is a prerequisite for all applications of ionizing radiation. This has been known since the very first radiation applications in medicine and biology, and increasing efforts are being made by radiation researchers to develop more reliable, effective and safe instruments, and to further improve dosimetric accuracy for all types of radiation used. Development of new techniques and instrumentation was particularly fast in the field of both medical diagnostic and therapeutic radiology. Thus, in Paris in October the IAEA held the latest symposium in its continuing series on dosimetry in medicine and biology. The last one was held in Vienna in 1975. High-quality dosimetry is obviously of great importance for human health, whether the objectives lie in the prevention and control of risks associated with the nuclear industry, in medical uses of radioactive substances or X-ray beams for diagnostic purposes, or in the application of photon, electron or neutron beams in radiotherapy. The symposium dealt with the following subjects: General aspects of dosimetry; Special physical and biomedical aspects; Determination of absorbed dose; Standardization and calibration of dosimetric systems; and Development of dosimetric systems. The forty or so papers presented and the discussions that followed them brought out a certain number of dominant themes, among which three deserve particular mention. - The recent generalization of the International System of Units having prompted a fundamental reassessment of the dosimetric quantities to be considered in calibrating measuring instruments, various proposals were advanced by the representatives of national metrology laboratories to replace the quantity 'exposure' (SI unit = coulomb/kg) by 'Kerma' or 'absorbed dose' (unit joule/kg, the special name of which is 'gray'), this latter being closer to the practical

  8. 2D convolution kernels of ionization chambers used for photon-beam dosimetry in magnetic fields: the advantage of small over large chamber dimensions

    Science.gov (United States)

    Khee Looe, Hui; Delfs, Björn; Poppinga, Daniela; Harder, Dietrich; Poppe, Björn

    2018-04-01

    This study aims at developing an optimization strategy for photon-beam dosimetry in magnetic fields using ionization chambers. Similar to the familiar case in the absence of a magnetic field, detectors should be selected under the criterion that their measured 2D signal profiles M(x,y) approximate the absorbed dose to water profiles D(x,y) as closely as possible. Since the conversion of D(x,y) into M(x,y) is known as the convolution with the ‘lateral dose response function’ K(x-ξ, y-η) of the detector, the ideal detector would be characterized by a vanishing magnetic field dependence of this convolution kernel (Looe et al 2017b Phys. Med. Biol. 62 5131–48). The idea of the present study is to find out, by Monte Carlo simulation of two commercial ionization chambers of different size, whether the smaller chamber dimensions would be instrumental to approach this aim. As typical examples, the lateral dose response functions in the presence and absence of a magnetic field have been Monte-Carlo modeled for the new commercial ionization chambers PTW 31021 (‘Semiflex 3D’, internal radius 2.4 mm) and PTW 31022 (‘PinPoint 3D’, internal radius 1.45 mm), which are both available with calibration factors. The Monte-Carlo model of the ionization chambers has been adjusted to account for the presence of the non-collecting part of the air volume near the guard ring. The Monte-Carlo results allow a comparison between the widths of the magnetic field dependent photon fluence response function K M(x-ξ, y-η) and of the lateral dose response function K(x-ξ, y-η) of the two chambers with the width of the dose deposition kernel K D(x-ξ, y-η). The simulated dose and chamber signal profiles show that in small photon fields and in the presence of a 1.5 T field the distortion of the chamber signal profile compared with the true dose profile is weakest for the smaller chamber. The dose responses of both chambers at large field size are shown to be altered by not

  9. Biokinetic data of various radioactive cationic molecules. An attempt at evaluation of significant chemical properties of myotropic agents

    International Nuclear Information System (INIS)

    Munze, R.; Kretzschmar, M.; Syhre, R.; Kampf, G.; Klotzer, D.; Guthert, I.; Bergmann, R.

    1986-01-01

    Research on lipophilic cationic radiopharmaceuticals has been established as an important field of modern radiopharmacology and experimental nuclear medicine. The present state is best demonstrated by scintigrams obtained with Tc-TBI (TBI = tertiary butylisocyanide). These images clearly reveal the advantage of these compounds, namely high information density, which resulted in an excellent delineation of activity accumulations, as well as the lasting drawback represented by partial overlapping of the right lobe of the liver in a certain region of the inferior wall of the heart. Current research is mainly focused on overcoming this disadvantage by synthesizing appropriate compounds with higher heart/liver uptake in man. A more sophisticated rationale than cationic charge and lipophilicity would be much appreciated. This paper deals with possible correlations between the biodistribution and biokinetics of such compounds, though not exclusively for technetium cations, and their important chemical properties such as composition, size, and polar regions within the lipophilic molecule, which are considered significant parameters

  10. Personnel neutron dosimetry

    International Nuclear Information System (INIS)

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs

  11. Status of neutron cross sections for reactor dosimetry

    International Nuclear Information System (INIS)

    Vlasov, M.F.; Fabry, A.; McElroy, W.N.

    1977-03-01

    The status of current international efforts to develop standardized sets of evaluated energy-dependent (differential) neutron cross sections for reactor dosimetry is reviewed. The status and availability of differential data are considered, some recent results of the data testing of the ENDF/B-IV dosimetry file using 252 Cf and 235 U benchmark reference neutron fields are presented, and a brief review is given of the current efforts to characterize and identify dosimetry benchmark radiation fields

  12. SU-E-T-247: Multi-Leaf Collimator Model Adjustments Improve Small Field Dosimetry in VMAT Plans

    Energy Technology Data Exchange (ETDEWEB)

    Young, L; Yang, F [University of Washington, Seattle, WA (United States)

    2014-06-01

    Purpose: The Elekta beam modulator linac employs a 4-mm micro multileaf collimator (MLC) backed by a fixed jaw. Out-of-field dose discrepancies between treatment planning system (TPS) calculations and output water phantom measurements are caused by the 1-mm leaf gap required for all moving MLCs in a VMAT arc. In this study, MLC parameters are optimized to improve TPS out-of-field dose approximations. Methods: Static 2.4 cm square fields were created with a 1-mm leaf gap for MLCs that would normally park behind the jaw. Doses in the open field and leaf gap were measured with an A16 micro ion chamber and EDR2 film for comparison with corresponding point doses in the Pinnacle TPS. The MLC offset table and tip radius were adjusted until TPS point doses agreed with photon measurements. Improvements to the beam models were tested using static arcs consisting of square fields ranging from 1.6 to 14.0 cm, with 45° collimator rotation, and 1-mm leaf gap to replicate VMAT conditions. Gamma values for the 3-mm distance, 3% dose difference criteria were evaluated using standard QA procedures with a cylindrical detector array. Results: The best agreement in point doses within the leaf gap and open field was achieved by offsetting the default rounded leaf end table by 0.1 cm and adjusting the leaf tip radius to 13 cm. Improvements in TPS models for 6 and 10 MV photon beams were more significant for smaller field sizes 3.6 cm or less where the initial gamma factors progressively increased as field size decreased, i.e. for a 1.6cm field size, the Gamma increased from 56.1% to 98.8%. Conclusion: The MLC optimization techniques developed will achieve greater dosimetric accuracy in small field VMAT treatment plans for fixed jaw linear accelerators. Accurate predictions of dose to organs at risk may reduce adverse effects of radiotherapy.

  13. Commissioning of a PTW 34070 large-area plane-parallel ionization chamber for small field megavoltage photon dosimetry.

    Science.gov (United States)

    Kupfer, Tom; Lehmann, Joerg; Butler, Duncan J; Ramanathan, Ganesan; Bailey, Tracy E; Franich, Rick D

    2017-11-01

    This study investigates a large-area plane-parallel ionization chamber (LAC) for measurements of dose-area product in water (DAP w ) in megavoltage (MV) photon fields. Uniformity of electrode separation of the LAC (PTW34070 Bragg Peak Chamber, sensitive volume diameter: 8.16 cm) was measured using high-resolution microCT. Signal dependence on angle α of beam incidence for square 6 MV fields of side length s = 20 cm and 1 cm was measured in air. Polarity and recombination effects were characterized in 6, 10, and 18 MV photons fields. To assess the lateral setup tolerance, scanned LAC profiles of a 1 × 1 cm 2 field were acquired. A 6 MV calibration coefficient, N D ,w, LAC , was determined in a field collimated by a 5 cm diameter stereotactic cone with known DAP w . Additional calibrations in 10 × 10 cm 2 fields at 6, 10, and 18 MV were performed. Electrode separation is uniform and agrees with specifications. Volume-averaging leads to a signal increase proportional to ~1/cos(α) in small fields. Correction factors for polarity and recombination range between 0.9986 to 0.9996 and 1.0007 to 1.0024, respectively. Off-axis displacement by up to 0.5 cm did not change the measured signal in a 1 × 1 cm 2 field. N D ,w, LAC was 163.7 mGy cm -2 nC -1 and differs by +3.0% from the coefficient derived in the 10 × 10 cm 2 6 MV field. Response in 10 and 18 MV fields increased by 1.0% and 2.7% compared to 6 MV. The LAC requires only small correction factors for DAP w measurements and shows little energy dependence. Lateral setup errors of 0.5 cm are tolerated in 1 × 1 cm 2 fields, but beam incidence must be kept as close to normal as possible. Calibration in 10 × 10 fields is not recommended because of the LAC's over-response. The accuracy of relative point-dose measurements in the field's periphery is an important limiting factor for the accuracy of DAP w measurements. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on

  14. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  15. The impact of exposure to radio frequency electromagnetic fields on chronic well-being in young people--a cross-sectional study based on personal dosimetry.

    Science.gov (United States)

    Heinrich, Sabine; Thomas, Silke; Heumann, Christian; von Kries, Rüdiger; Radon, Katja

    2011-01-01

    A possible influence of radio frequency electromagnetic field (RF EMF) exposure on health outcomes was investigated in various studies. The main problem of previous studies was exposure assessment. The aim of our study was the investigation of a possible association between RF EMF and chronic well-being in young persons using personal dosimetry. 3022 children and adolescents were randomly selected from the population registries of four Bavarian cities in Germany (participation 52%). Personal interview data on chronic symptoms, socio-demographic characteristics and potential confounders were collected. A 24-h radio frequency exposure profile was generated using a personal dosimeter. Exposure levels over waking hours were expressed as mean percentage of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference level. Half of the children and nearly every adolescent owned a mobile phone which was used only for short durations per day. Measured exposure was far below the current ICNIRP reference levels. The most reported chronic symptom in children and adolescents was fatigue. No statistically significant association between measured exposure and chronic symptoms was observed. Our results do not indicate an association between measured exposure to RF EMF and chronic well-being in children and adolescents. Prospective studies investigating potential long-term effects of RF EMF are necessary to confirm our results. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Cadmium bioavailability to Hyalella azteca from a periphyton diet compared to an artificial diet and application of a biokinetic model

    Energy Technology Data Exchange (ETDEWEB)

    Golding, Lisa A., E-mail: lisa.golding@csiro.au [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Borgmann, Uwe [Environment Canada, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada); George Dixon, D. [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2013-01-15

    Differences between the bioavailability of cadmium in a periphyton diet and an artificial laboratory diet (TetraMin{sup Registered-Sign }) have important consequences for predicting bioaccumulation and toxicity in the freshwater amphipod Hyalella azteca. The assimilation efficiency (AE) of Cd was compared between periphyton and TetraMin{sup Registered-Sign} at low (1510 and 358 nmol/g ash-free dry mass respectively) and chronically lethal (31,200 and 2890 nmol/g ash-free dry mass respectively) Cd concentrations and in fresh and dry forms using a {sup 109}Cd radiotracer pulse-chase feeding technique. Assimilation efficiency of Cd from periphyton (AE = 3-14%) was lower than that for TetraMin{sup Registered-Sign} (AE = 44-86%) regardless of Cd concentration or food form. Ingestion rate (IR) was lower for dry than fresh forms of periphyton (0.042 and 0.16 g AFDM/g H. azteca/day respectively) and TetraMin{sup Registered-Sign} (0.19 and 0.87 AFDM/g H. azteca/day respectively) and depuration rate (k{sub e}) did not differ statistically with food type, form or Cd concentration (0.032-0.094 d{sup -1}). Biokinetic models with parameters of AE, IR and k{sub e} were used to estimate bioaccumulation from the separate food types. These estimates were compared to those from an independent chronic Cd saturation bioaccumulation model. While the model estimates did not concur, a sensitivity analysis indicated that AE and IR were the most influential biokinetic model parameters for Cd in periphyton and TetraMin{sup Registered-Sign} respectively. It was hypothesized that AE was underestimated for Cd in periphyton due to a non-adapted gut enzyme system and IR was overestimated for Cd in TetraMin{sup Registered-Sign} due to an initial rapid ingestion phase in H. azteca's feeding habits. This research demonstrated the importance of using ecologically relevant food types in laboratory experiments and verifying acute biokinetic model predictions of dietary metal contribution with

  17. Neutron dosimetry - A review

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J W

    1955-03-29

    This review summarizes information on the following subjects: (1) physical processes of importance in neutron dosimetry; (2) biological effects of neutrons; (3) neutron sources; and (4) instruments and methods used in neutron dosimetry. Also, possible improvements in dosimetry instrumentation are outlined and discussed. (author)

  18. Dosimetry Characterization of the Neutron Fields of the Intermediate Temporary Storage of the Trillo Nuclear Power Plant

    International Nuclear Information System (INIS)

    Campo Blanco, X.

    2015-01-01

    The Neutron Standards Laboratory of CIEMAT, in collaboration with the Trillo Nuclear Power Plant, has conducted a detailed dosimetric and spectrometric characterization of the neutron fields at the Intermediate Temporary Storage of the Trillo Nuclear Power Plant, as well as the neutron fields of ENSA-DPT spent fuel casks. For neutron measurements, neutron monitors and a Bonner spheres spectrometry system have been used. In addition, a Monte Carlo model of the installation and the cask has been developed and validated.

  19. Speciation and internal dosimetry: from chemical species to dosimetric models

    International Nuclear Information System (INIS)

    Paquet, F.; Frelon, S.; Cote, G.; Madic, C.

    2004-01-01

    Speciation studies refer to the distribution of species in a particular sample or matrix. These studies are necessary to improve the description, understanding and prediction of trace element kinetics and toxicity. In case of internal contamination with radionuclides, speciation studies could help to improve both the biokinetic and dosimetric models for radionuclides. There are different methods to approach the speciation of radionuclide in a biological system, depending on the degree of accuracy needed and the level of uncertainties accepted. Among them, computer modelling and experimental determination are complementary approaches. This paper describes what is known about speciation of actinides in blood, GI-tract, liver and skeleton and of their consequences in terms of internal dosimetry. The conclusion is that such studies provide very valuable data and should be targeted in the future on some specific tissues and biomolecules. (authors)

  20. The contribution of chemical speciation to internal dosimetry

    International Nuclear Information System (INIS)

    Paquet, F.; Frelon, S.; Cote, G.; Madic, C.

    2003-01-01

    Speciation studies refer to the distribution of species in a particular sample or matrix. These studies are necessary to improve the description, understanding and prediction of trace element kinetics and toxicity. In the case of internal contamination with radionuclides, speciation studies could help to improve both the biokinetic and dosimetric models for radionuclides. There are different methods to approach the speciation of radionuclides in a biological system, depending on the degree of accuracy needed and the level of uncertainties accepted. Among them, computer modelling and experimental determination are complementary approaches. This paper describes what is known about speciation of actinides in blood, GI tract, liver and skeleton and of their consequences in terms of internal dosimetry. The conclusion is that such studies provide very valuable data and should be targeted in the future on some specific tissues and biomolecules. (author)

  1. Different biokinetics of nanomedicines linking to their toxicity; an overview

    Directory of Open Access Journals (Sweden)

    Abdollahi Mohammad

    2013-02-01

    Full Text Available Abstract In spite of the extreme rise to the knowledge of nanotechnology in pharmaceutical sciences, there are currently limited experimental works studying the interactions between nanoparticles (NPs and the biological system. Adjustment of size and surface area plays the main role in the reaction between NPs and cells leading to their increased entrance into cells through skin, gastrointestinal and respiratory system. Moreover, change in physicochemical reactivity of NPs causes them to interact with circulatory and cellular proteins differentially leading to the altered parameters of their biokinetics, including adsorption, distribution, translocation, transformation, and elimination. A direct relationship between the surface area, reactive oxygen species generating capability, and proinflammatory effects of NPs have been found in respiratory tract toxicity. Additionally, complement-mediated hypersensitivity reactions to liposomes and other lipid-based nanodrugs have been well defined. Inhalation studies of some NPs have confirmed the translocation of inhaled materials to extra pulmonary organs such as central nervous system (CNS via olfactory neurons and induction of inflammatory response. Injectable uncoated NPs have a tendency to remain on the injection site while the poly ethanol glycol (PEG-coated NPs can be notably drained from the injection site to get as far as the lymph nodes where they accumulate. This confirms the existence of channels within the extracellular matrix for NPs to move along. Furthermore, induction of DNA strand breaks and formation of micronuclei have been recorded for exposure to some NPs such as single-walled carbon nanotubes. In the recent years, most of the studies have simply outlined better efficacy of nanodrugs, but few discussed their possible toxic reactions specially if used chronically. Therefore, we emphasize that this part of the nanoscience must not be undermined and toxicologists must be sensitive to

  2. SU-F-T-216: Evaluating Dosimetry Accuracy of a Treatment Planning System On Small Proton Fields

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, M; Xiao, Z; Zou, J; Chen, T; Yue, N [Rutgers University, New Brunswick, NJ (United States)

    2016-06-15

    Purpose: This study is aiming to identify the smallest field size for which a treatment planning system (TPS) can accurately calculate the relative dose distribution. The finding would be used as a guideline to choose the smallest proton field for clinical treatment. Methods: Mevion S250™ double scattering proton delivery system and Eclipse™ TPS (Varian) with pencil beam convolution (PBC) dose algorithm were used in this study. Square sized fields of 1 cm, 2 cm, 3 cm, 4 cm, 5 cm, and 10 cm were planned on a cubical water phantom with iso-center placed at 10 cm depth. All beams used the same proton beam option: range 15 cm and modulation 10 cm. Dose in water was calculated without any compensator. Gafchromic™ EBT3 film and diode detectors were used to measure the central axis dose distribution and lateral dose profiles at 5 cm, 10 cm, and 14 cm depth. Results: The preliminary film measurement shows good agreement between Eclipse calculated lateral dose profiles for all tested field sizes. The differences on full width half maximum were ≤ 1 mm while the differences on the penumbras were between 1 mm and 2 mm between Eclipse and film. For the depth dose, Eclipse results matched well with film measurements for field sizes down to 2 cm{sup 2}. With smaller field size of 1 cm{sup 2}, Eclipse was able to predict the decreasing of SOBP due to the lack of lateral charged particle equilibrium in depth. However, it did not match the film measurement. Diode measurement results will be available at the time of presentation. Conclusion: The PBC dose algorithm in Eclipse can accurately calculate relative dose distribution in double scattered proton system for field size down to 2 cm{sup 2}.

  3. Chemical dosimetry principles in high dose dosimetry

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.

    2016-01-01

    In radiation processing, activities of principal concern are process validation and process control. The objective of such formalized procedures is to establish documentary evidence that the irradiation process has achieved the desired results. The key element of such activities is inevitably a well characterized reliable dosimetry system that is traceable to recognized national and international dosimetry standards. Only such dosimetry systems can help establish the required documentary evidence. In addition, industrial radiation processing such as irradiation of foodstuffs and sterilization of health careproducts are both highly regulated, in particular with regard to dose. Besides, dosimetry is necessary for scaling up processes from the research level to the industrial level. Thus, accurate dosimetry is indispensable

  4. The work programme of EURADOS on internal and external dosimetry.

    Science.gov (United States)

    Rühm, W; Bottollier-Depois, J F; Gilvin, P; Harrison, R; Knežević, Ž; Lopez, M A; Tanner, R; Vargas, A; Woda, C

    2018-01-01

    Since the early 1980s, the European Radiation Dosimetry Group (EURADOS) has been maintaining a network of institutions interested in the dosimetry of ionising radiation. As of 2017, this network includes more than 70 institutions (research centres, dosimetry services, university institutes, etc.), and the EURADOS database lists more than 500 scientists who contribute to the EURADOS mission, which is to promote research and technical development in dosimetry and its implementation into practice, and to contribute to harmonisation of dosimetry in Europe and its conformance with international practices. The EURADOS working programme is organised into eight working groups dealing with environmental, computational, internal, and retrospective dosimetry; dosimetry in medical imaging; dosimetry in radiotherapy; dosimetry in high-energy radiation fields; and harmonisation of individual monitoring. Results are published as freely available EURADOS reports and in the peer-reviewed scientific literature. Moreover, EURADOS organises winter schools and training courses on various aspects relevant for radiation dosimetry, and formulates the strategic research needs in dosimetry important for Europe. This paper gives an overview on the most important EURADOS activities. More details can be found at www.eurados.org .

  5. Dosimetry techniques applied to thermoluminescent age estimation

    International Nuclear Information System (INIS)

    Erramli, H.

    1986-12-01

    The reliability and the ease of the field application of the measuring techniques of natural radioactivity dosimetry are studied. The natural radioactivity in minerals in composed of the internal dose deposited by alpha and beta radiations issued from the sample itself and the external dose deposited by gamma and cosmic radiations issued from the surroundings of the sample. Two technics for external dosimetry are examined in details. TL Dosimetry and field gamma dosimetry. Calibration and experimental conditions are presented. A new integrated dosimetric method for internal and external dose measure is proposed: the TL dosimeter is placed in the soil in exactly the same conditions as the sample ones, during a time long enough for the total dose evaluation [fr

  6. Design and experimental testing of air slab caps which convert commercial electron diodes into dual purpose, correction-free diodes for small field dosimetry.

    Science.gov (United States)

    Charles, P H; Cranmer-Sargison, G; Thwaites, D I; Kairn, T; Crowe, S B; Pedrazzini, G; Aland, T; Kenny, J; Langton, C M; Trapp, J V

    2014-10-01

    Two diodes which do not require correction factors for small field relative output measurements are designed and validated using experimental methodology. This was achieved by adding an air layer above the active volume of the diode detectors, which canceled out the increase in response of the diodes in small fields relative to standard field sizes. Due to the increased density of silicon and other components within a diode, additional electrons are created. In very small fields, a very small air gap acts as an effective filter of electrons with a high angle of incidence. The aim was to design a diode that balanced these perturbations to give a response similar to a water-only geometry. Three thicknesses of air were placed at the proximal end of a PTW 60017 electron diode (PTWe) using an adjustable "air cap". A set of output ratios (ORDet (fclin) ) for square field sizes of side length down to 5 mm was measured using each air thickness and compared to ORDet (fclin) measured using an IBA stereotactic field diode (SFD). kQclin,Qmsr (fclin,fmsr) was transferred from the SFD to the PTWe diode and plotted as a function of air gap thickness for each field size. This enabled the optimal air gap thickness to be obtained by observing which thickness of air was required such that kQclin,Qmsr (fclin,fmsr) was equal to 1.00 at all field sizes. A similar procedure was used to find the optimal air thickness required to make a modified Sun Nuclear EDGE detector (EDGEe) which is "correction-free" in small field relative dosimetry. In addition, the feasibility of experimentally transferring kQclin,Qmsr (fclin,fmsr) values from the SFD to unknown diodes was tested by comparing the experimentally transferred kQclin,Qmsr (fclin,fmsr) values for unmodified PTWe and EDGEe diodes to Monte Carlo simulated values. 1.0 mm of air was required to make the PTWe diode correction-free. This modified diode (PTWeair) produced output factors equivalent to those in water at all field sizes (5-50 mm

  7. Dosimetry system 1986

    International Nuclear Information System (INIS)

    Woolson, William A.; Egbert, Stephen D.; Gritzner, Michael L.

    1987-01-01

    In May 1983, the authors proposed a dosimetry system for use by the Radiation Effects Research Foundation (RERF) that would incorporate the new findings and calculations of the joint United States - Japan working groups on the reassessment of A-bomb dosimetry. The proposed dosimetry system evolved from extensive discussions with RERF personnel, numerous meetings of the scientists from Japan and the United States involved in the dosimetry reassessment research, and requirements expressed by epidemiologists and radiobiologists on the various review panels. The dosimetry system proposed was based on considerations of the dosimetry requirements for the normal work of RERF and for future research in radiobiology, the computerized input data on A-bomb survivors available in the RERF data base, the level of detail, precision, and accuracy of various components of the dosimetric estimates, and the computer resources available at RERF in Hiroshima. These discussions and our own experience indicated that, in light of the expansion of computer and radiation technologies and the desire for more detail in the dosimetry, an entirely new approach to the dosimetry system was appropriate. This resulted in a complete replacement of the T65D system as distinguished from a simpler approach involving a renormalization of T65D parameters to reflect the new dosimetry. The proposed dosimetry system for RERF and the plan for implementation was accepted by the Department of Energy (DOE) Working Group on A-bomb Dosimetry chaired by Dr. R.F. Christy. The dosimetry system plan was also presented to the binational A-bomb dosimetry review groups for critical comment and was discussed at joint US-Japan workshop. A prototype dosimetry system incorporating preliminary dosimetry estimates and applicable to only a limited set of A-bomb survivors was installed on the RERF computer system in the fall of 1984. This system was successfully operated at RERF and provided an initial look at the impact of

  8. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  9. Monte Carlo simulations of the electric field close to the body in realistic environments for application in personal radiofrequency dosimetry

    International Nuclear Information System (INIS)

    Iskra, S.; McKenzie, R.; Cosic, I.

    2011-01-01

    Personal dosemeters can play an important role in epidemiological studies and in radiofrequency safety programmes. In this study, a Monte Carlo approach is used in conjunction with the finite difference time domain method to obtain distributions of the electric field strength close to a human body model in simulated realistic environments. The field is a proxy for the response of an ideal body-worn electric field dosemeter. A set of eight environments were modelled based on the statistics of Rayleigh, Rice and log-normal fading to simulate outdoor and indoor multi-path exposures at 450, 900 and 2100 MHz. Results indicate that a dosemeter mounted randomly within 10-50 mm of the adult or child body model (torso region) will on average underestimate the spatially averaged value of the incident electric field strength by a factor of 0.52 to 0.74 over the frequencies of 450, 900 and 2100 MHz. The uncertainty in results, assessed at the 95 % confidence level (between the 2.5. and 97.5. percentiles) was largest at 2100 MHz and smallest at 450 MHz. (authors)

  10. High energy dosimetry

    International Nuclear Information System (INIS)

    Ruhm, W.

    2010-01-01

    Full text: Currently, quantification of doses from high-energy radiation fields is a topical issue. This is so because high-energy neutrons play an important role for radiation exposure of air crew members and personnel outside the shielding of ion therapy facilities. In an effort to study air crew exposure from cosmic radiation in detail, two Bonner Sphere Spectrometers (BSSs) have recently been installed to measure secondary neutrons from cosmic radiation, one at the environmental research station 'Schneefernerhaus' at an altitude of 2650 m on the Zugspitze mountain, Germany, the other at the Koldewey station close to the North Pole on Spitsbergen. Based on the measured neutron fluence distributions and on fluence-to-dose conversion coefficients, mean ambient dose equivalent rate values of 75.0 ± 2.9 nSv/h and 8.7 ± 0.6 nSv/h were obtained for October 2008, respectively. Neutrons with energies above about 20 MeV contribute about 50% to dose, at 2650 m. Ambient dose equivalent rates measured by means of a standard rem counter and an extended rem counter at the Schneefernerhaus confirm this result. In order to study the response of state-of-the-art radiation instrumentation in such a high-energy radiation field, a benchmark exercise that included both measurements in and simulation of the stray neutron radiation field at the high-energy particle accelerator at GSI, Germany, were performed. This CONRAD (COordinated Network for RAdiation Dosimetry) project was funded by the European Commission, and the organizational framework was provided by the European Radiation Dosimetry Group, EURADOS. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers suggest the neutron fluence distributions to be very similar to those of secondary neutrons from cosmic radiation. The results of this intercomparison exercise in terms of ambient dose equivalent are also discussed

  11. Clinical dosimetry using mosfets

    International Nuclear Information System (INIS)

    Ramani, Ramaseshan; Russell, Stephen; O'Brien, Peter

    1997-01-01

    Purpose: The use of metal oxide-silicon field effect transistors (MOSFETs) as clinical dosimeters is demonstrated for a number of patients with targets at different clinical sites. Methods and Materials: Commercially available MOSFETs were characterized for energy response, angular dependency of response, and effect of accumulated dose on sensitivity and some inherent properties of MOSFETs. The doses determined both by thermoluminescence dosimetry (TLD) and MOSFETs in clinical situation were evaluated and compared to expected doses determined by calculation. Results: It was observed that a standard calibration of 0.01 Gy/mV gave MOSFET determined doses which agreed with expected doses to within 5% at the 95% confidence limit for photon beams from 6 to 25 MV and electron beams from 5 to 14 MeV. An energy-dependent variation in response of up to 28% was observed between two orientations of a MOSFET. The MOSFET doses compared very well with the doses estimated by TLDs, and the patients tolerated MOSFETs very well. A standard deviation of 3.9% between expected dose and MOSFET determined dose was observed, while for TLDs the standard deviation was 5.1%. The advantages and disadvantages of using MOSFETs for clinical dosimetry are discussed in detail. Conclusion: It was concluded that MOSFETs can be used as clinical dosimeters and can be a good alternative to TLDs. However, they have limitations under certain clinical situations

  12. Non-conventional personal dosimetry techniques

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1984-01-01

    Established dosimetry has achieved a high standard in personnel monitoring. This applies particularly to photon dosimetry. Nevertheless, even in photon dosimetry, improvements and changes are being made. The reason may be technological progress, or the introduction of new tasks on the basis of the recommendations of international bodies (e.g. the new ICRU measurement unit) of national legislation. Since we are restricting ourselves here to technical trends the author would like to draw attention to various activities of current interest, e.g. the computation of receptor-related conversion coefficients from personal dose to organ or body doses, taking into account the conditions of exposure with respect to differential energy and angular distribution of the radiation field. Realistic data on exposure geometry are taken from work place analyses. Furthermore, the data banks of central personal dosimetry services are subject to statistical evaluation and radiation protection trend analysis. Technological progress and developments are considered from the point of view of personal dosimetry, partial body or extremity dosimetry and accidental dosimetry

  13. Fast, large field-of-view, telecentric optical-CT scanning system for 3D radiochromic dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, A; Oldham, M, E-mail: ast5@duke.ed [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

    2010-11-01

    We describe initial experiences with an in-house, fast, large field-of-view optical-CT telecentric scanner (the Duke Large field of view Optical-CT Scanner (DLOS)). The DLOS system is designed to enable telecentric optical-CT imaging of dosimeters up to 24 cm in diameter with a spatial resolution of 1 mm{sup 3}, in approximately 10 minutes. These capabilities render the DLOS system a unique device at present. The system is a scaled up version of early prototypes in our lab. This scaling introduces several challenges, including the accurate measurement of a greatly increased range of light attenuation within the dosimeter, and the need to reduce even minor reflections and scattered light within the imaging chain. We present several corrections and techniques that enable accurate, low noise, 3D dosimetery with the DLOS system.

  14. An evaluation of gating window size, delivery method, and composite field dosimetry of respiratory-gated IMRT

    International Nuclear Information System (INIS)

    Hugo, Geoffrey D.; Agazaryan, Nzhde; Solberg, Timothy D.

    2002-01-01

    A respiratory gating system has been developed based on a commercial patient positioning system. The purpose of this study is to investigate the ability of the gating system to reproduce normal, nongated IMRT operation and to quantify the errors produced by delivering a nongated IMRT treatment onto a moving target. A moving phantom capable of simultaneous two-dimensional motion was built, and an analytical liver motion function was used to drive the phantom. Studies were performed to assess the effect of gating window size and choice of delivery method (segmented and dynamic multileaf collimation). Additionally, two multiple field IMRT cases were delivered to quantify the error in gated and nongated IMRT with motion. Dosimetric error between nonmoving and moving deliveries is related to gating window size. By reducing the window size, the error can be reduced. Delivery error can be reduced for both dynamic and segmented delivery with gating. For the implementation of dynamic IMRT delivery in this study, dynamic delivery was found to generate larger delivery errors than segmented delivery in most cases studied. For multiple field IMRT delivery, the largest errors were generated in regions where high field modulation was present parallel to the axis of motion. Gating was found to reduce these large errors to clinically acceptable levels

  15. Personal Dosimetry Enhancement for Underground Workplaces

    Directory of Open Access Journals (Sweden)

    L. Thinová

    2005-01-01

    Full Text Available Personal dosimetry for underground workers mainly concerns measurement of the concentration of radon (and its daughters and the correct application of the data in dose calculation, using a biokinetic model for lung dosimetry. A conservative approach for estimating the potential dose in caves (or underground is based on solid state alpha track detector measurements. The obtained dataset is converted into an annual effective dose in agreement with the ICRP recommendations using the “cave factor”, the value of which depends on the spectrum of aerosol particles, or on the proportional representation of the unattached and the attached fraction and on the equilibrium factor. The main difference between apartments and caves is the absence of aerosol sources, high humidity, low ventilation rate and the uneven surface in caves. A more precisely determined dose value would have a significant impact on radon remedies or on restricting the time workers stay underground. In order to determine  how the effective dose is calculated, it is necessary to divide these areas into distinct categories by the following measuring procedures: continual radon measurement (to capture the differences in EERC between working hours and night-time, and also between daily and seasonal radon concentration variations; regular measurements of radon and its daughters to estimate the equilibrium factor and the presence of 218Po; regular indoor air flow measurements to study the location of the radon supply and its transfer among individual areas of the cave; natural radioactive element content evaluation in subsoils and in water inside/outside, a study of the radon sources in the cave; aerosol particle-size spectrum measurements to determine the free fraction; monitoring the behaviour of guides and workers to record the actual time spent in the cave, in relation to the continuously monitored levels of Rn concentration. 

  16. Dosimetry as an integral part of radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1999-01-01

    Different connections between high-dose dosimetry and radiation processing are discussed. Radiation processing cannot be performed without proper dosimetry. Accurate high dose and high dose rate dosimetry exhibits several aspects: first of all it is the preservation of the quality of the product, then fulfillment of legal aspects and last but not the least the safety of processing. Further, seldom discussed topics are as follow: dosimetric problems occurring with double-side EB irradiations, discussed in connection with the deposition of electric charge during electron beam irradiation. Although dosimetry for basic research and for medical purposes are treated here only shortly, some conclusions reached from these fields are considered in dosimetry for radiation processing. High-dose dosimetry of radiation has become a separate field, with many papers published every year, but applied dosimetric projects are usually initiated by a necessity of particular application. (author)

  17. Proceedings of the 5. symposium on neutron dosimetry. Beam dosimetry

    International Nuclear Information System (INIS)

    Schraube, H.; Burger, G.; Booz, J.

    1985-01-01

    Proceedings of the fifth symposium on neutron dosimetry, organized at Neuherberg, 17-21 September 1984, by the Commission of the European Communities and the GSF Neuherberg, with the co-sponsorship of the US Department of Energy, Office of Health and Environmental Research. The proceedings deal with research on concepts, instruments and methods in radiological protection for neutrons and mixed neutron-gamma fields, including the generation, collection and evaluation of new dosimetric data, the derivation of relevant radiation protection quantitites, and the harmonization of experimental methods and instrumentation by intercomparison programmes. Besides radiation protection monitoring, the proceedings also report on the improvement of neutron beam dosimetry in the fields of radiobiology and radiation therapy

  18. INTERCOMPARISON ON THE MEASUREMENT OF THE QUANTITY PERSONAL DOSE EQUIVALENT HP(10) IN PHOTON FIELDS. LINEARITY DEPENDENCE, LOWER LIMIT OF DETECTION AND UNCERTAINTY IN MEASUREMENT OF DOSIMETRY SYSTEMS OF INDIVIDUAL MONITORING SERVICES IN GABON AND GHANA.

    Science.gov (United States)

    Ondo Meye, P; Schandorf, C; Amoako, J K; Manteaw, P O; Amoatey, E A; Adjei, D N

    2017-12-01

    An inter-comparison study was conducted to assess the capability of dosimetry systems of individual monitoring services (IMSs) in Gabon and Ghana to measure personal dose equivalent Hp(10) in photon fields. The performance indicators assessed were the lower limit of detection, linearity and uncertainty in measurement. Monthly and quarterly recording levels were proposed with corresponding values of 0.08 and 0.025 mSv, and 0.05 and 0.15 mSv for the TLD and OSL systems, respectively. The linearity dependence of the dosimetry systems was performed following the requirement given in the Standard IEC 62387 of the International Electrotechnical Commission (IEC). The results obtained for the two systems were satisfactory. The procedure followed for the uncertainty assessment is the one given in the IEC technical report TR62461. The maximum relative overall uncertainties, in absolute value, expressed in terms of Hp(10), for the TL dosimetry system Harshaw 6600, are 44. 35% for true doses below 0.40 mSv and 36.33% for true doses ≥0.40 mSv. For the OSL dosimetry system microStar, the maximum relative overall uncertainties, in absolute value, are 52.17% for true doses below 0.40 mSv and 37.43% for true doses ≥0.40 mSv. These results are in good agreement with the requirements for accuracy of the International Commission on Radiological protection. When expressing the uncertainties in terms of response, comparison with the IAEA requirements for overall accuracy showed that the uncertainty results were also acceptable. The values of Hp(10) directly measured by the two dosimetry systems showed a significant underestimation for the Harshaw 6600 system, and a slight overestimation for the microStar system. After correction for linearity of the measured doses, the two dosimetry systems gave better and comparable results. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Contribution of the Nea data bank in the field of calculation codes in radiation protection, radio physics and dosimetry

    International Nuclear Information System (INIS)

    Kodeli, I.; Sartori, E.

    2003-01-01

    The Nuclear energy agency is a specialised agency of OECD (organization economic co-operation and development). These missions are to help its members to keep and improve by international cooperation, the scientific, technological and legal bases necessary to a peaceful use of nuclear energy. Nea includes twenty eight countries. Nea works in collaboration with IAEA. The field of activities concerns the acquisition, validation and distribution of nuclear data, calculation codes and experiments. To help users, it organises conferences and training about the calculation codes that it shares out. (N.C.)

  20. The CERN-EU high-energy reference field (CERF) facility for dosimetry at commercial flight altitudes and in space.

    Science.gov (United States)

    Mitaroff, A; Cern, M Silari

    2002-01-01

    A reference facility for the calibration and intercomparison of active and passive detectors in broad neutron fields has been available at CERN since 1992. A positively charged hadron beam (a mixture of protons and pions) with momentum of 120 GeV/c hits a copper target, 50 cm thick and 7 cm in diameter. The secondary particles produced in the interaction traverse a shield, at 90 degrees with respect to the direction of the incoming beam. made of either 80 to 160 cm of concrete or 40 cm of iron. Behind the iron shield, the resulting neutron spectrum has a maximum at about 1 MeV, with an additional high-energy component. Behind the 80 cm concrete shield, the neutron spectrum has a second pronounced maximum at about 70 MeV and resembles the high-energy component of the radiation field created by cosmic rays at commercial flight altitudes. This paper describes the facility, reports on the latest neutron spectral measurements, gives an overview of the most important experiments performed by the various collaborating institutions over recent years and briefly addresses the possible application of the facility to measurements related to the space programme.

  1. The CERN-EU high-energy reference field (CERF) facility for dosimetry at commercial flight altitudes and in space

    CERN Document Server

    Mitaroff, Angela

    2002-01-01

    A reference facility for the calibration and intercomparison of active and passive detectors in broad neutron fields has been available at CERN since 1992. A positively charged hadron beam (a mixture of protons and pions) with momentum of 120 GeV/c hits a copper target, 50 cm thick and 7 cut in diameter. The secondary particles produced in the interaction traverse a shield, at 90 degrees with respect to the direction of the incoming beam, made of either 80 to 160 cm of concrete or 40 cm of iron. Behind the iron shield, the resulting neutron spectrum has a maximum at about 1 MeV, with an additional high-energy component. Behind the 80 cm concrete shield, the neutron spectrum has a second pronounced maximum at about 70 MeV and resembles the high-energy component of the radiation field created by cosmic rays at commercial flight altitudes. This paper describes the facility, reports on the latest neutron spectral measurements, gives an overview of the most important experiments performed by the various collaborat...

  2. Basis for the ICRP's age-specific biokinetic model for uranium

    International Nuclear Information System (INIS)

    Leggett, R.W.

    1994-01-01

    In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is developing age-specific biokinetic models and dose coefficients for environmentally important radionuclides. This paper describes the ICRP's age-specific biokinetic model for uranium. The model is constructed within a physiologically based framework originally developed for application to the alkaline earth elements but sufficiently general to apply to the larger class of bone-volume-seeking elements. Transfer rates for a reference adult are based mainly on: (1) measurements of uranium in blood and excreta of several human subjects who were intravenously injected with uranium; (2) postmortem measurements of uranium in tissues of some of those subjects; (3) postmortem measurements of uranium in tissues of occupationally and non-occupationally exposed subjects; (4) data on baboons, dogs, and smaller laboratory animals exposed to uranium for experimental purposes; and (5) consideration of the physiological processes thought to control retention and translocation of uranium in the body. Transfer rates for the adult are extended to children by application of a set of generic assumptions applied by the ICRP to calcium-like elements. These assumptions were derived mainly from observations of the age-specific biokinetics of the alkaline earth elements and lead in humans and laboratory animals but are consistent with available age-specific biokinetic data on uranium. 82 refs., 17 figs., 8 tabs

  3. A profile of Biokinetics service provided by the University of Kwa ...

    African Journals Online (AJOL)

    Biokinetics can be viewed as an emerging member of the South African health professions in comparison to the longstanding professions of physiotherapy, chiropractics and occupational therapy which were established in 1924, 1939 and 1945, respectively. The aim of this investigation was to determine the profile of the ...

  4. L-alanine detector characterization for dosimetry of small fields in SBRT with VMAT techniques; Caracterizacao do detector de L-alanina para dosimetria de campos pequenos em SBRT com a tecnica de VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Mazaro, Sarah J.; Peres, Leonardo [Instituto Nacional de Cancer (INCA), Rio de Janeiro, RJ (Brazil); Baffa, Oswaldo, E-mail: sarahmazaro@yahoo.com.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Departamento de Fisica

    2016-07-01

    New radiotherapy treatment techniques have some problems such as: the dosimetric and geometric of the beam and small fields. Determination of the prescribed dose on the target volume in small fields is hampered due to lack of lateral electronic equilibrium and steep dose gradient along the edges of fields. The choice of radiation better detector becomes important in the dosimetry of small fields. Alanine detector has been shown to be a good choice for measurements of high doses of radiation in small fields. This study aims to characterize the L-alanine detector through the dosimetric tests for SBRT in VMAT techniques. L-alanine response showed a strong linear correlation with the dose (R ² = 0.9865), with significant angles and dose rate dependencies (14%) and (15%) respectively, and minor with the small field size (maximum 4% deviation). (author)

  5. Cross sections required for FMIT dosimetry

    International Nuclear Information System (INIS)

    Gold, R.; McElroy, W.N.; Lippincott, E.P.; Mann, F.M.; Oberg, D.L.; Roberts, J.H.; Ruddy, F.H.

    1980-01-01

    The Fusion Materials Irradiation Test (FMIT) facility, currently under construction, is designed to produce a high flux of high energy neutrons for irradiation effects experiments on fusion reactor materials. Characterization of the flux-fluence-spectrum in this rapidly varying neutron field requires adaptation and extension of currently available dosimetry techniques. This characterization will be carried out by a combination of active, passive, and calculational dosimetry. The goal is to provide the experimenter with accurate neutron flux-fluence-spectra at all positions in the test cell. Plans have been completed for a number of experimental dosimetry stations and provision for these facilities has been incorporated into the FMIT design. Overall needs of the FMIT irradiation damage program delineate goal accuracies for dosimetry that, in turn, create new requirements for high energy neutron cross section data. Recommendations based on these needs have been derived for required cross section data and accuracies

  6. Dosimetry of fast neutrons

    International Nuclear Information System (INIS)

    Jahr, R.

    1975-03-01

    Following an explanation of the physical fundamentals of neutron dosimetry, the special needs in medicine and biology are gone into. It is shown that the dose equivalent used in radiation protection simplifies in an undue manner the complicated dependence of the biological effects. The reason for this is the fact that the RBE for heavy recoil nuclei, amongst others, depends on the energy and sort of particle, whereas it is approximately equal to one for electrons independent of the energy. It is thus necessary in the fields of biology and medicine to have additional information on energy spectra of the neutrons as well as of all charged secondary particles as a function of the position in the phantom. These are obtained partly by calculation and partly by special dosemeters. The accuracy achieved so far is 5%. (ORU/LH) [de

  7. Dosimetry of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez C, G; Restrepo, J; Aguirre, C A [Hospital Universitario del Valle, Cali (Colombia)

    1996-08-01

    The systemic therapy of breast cancer has also changed profoundly during the last 60 years, and in this time the integration of treatment modalities involve a major area of investigation. The dosimetry of breast cancer presents different complications which can range from the Physician`s handling of the neoplasia up to the simple aspects of physical simulation, contour design, radiation fields, irregular surfaces and computer programs containing mathematical equations which differ little or largely with the reality of the radiation distribution into the volume to be irradiated. We have studied the problem using two types of measurements to determine how the radiation distribution is in irregular surfaces, and designing an easier skill to be used with each patient, in order to optimize the treatment with respect to the simulation and verification process. (author). 7 refs.

  8. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    International Nuclear Information System (INIS)

    Rathbone, Bruce A.

    2006-01-01

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL's Hanford External Dosimetry Program which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL's Electronic Records & Information Capture Architecture (ERICA) database

  9. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2005-02-25

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database.

  10. Neutron personal dosimetry: state-of-art

    International Nuclear Information System (INIS)

    Spurný, František

    2005-03-01

    State-of-art of the personal neutron dosimetry is presented, analysed and discussed. Particular attention is devoted to the problems of this type of the dosimetry of external exposure for radiation fields at nuclear power plants. A review of general problems of neutron dosimetry is given and the active individual dosimetry methods available and/or in the stage of development are briefly reviewed. Main attention is devoted to the analysis of the methods available for passive individual neutron dosimetry. The characteristics of these dosemeters were studied and are compared: their energy response functions, detection thresholds and the highest detection limits, the linearity of response, the influence of environmental factors, etc. Particular attention is devoted to their behavior in reactor neutron fields. It is concluded that the choice of the neutron personal dosemeter depends largely on the conditions in which the instrument should be used (neutron spectrum, the level of exposure and the exposure rate, etc.). The results obtained with some of these dosemeters during international intercomparisons are also presented. Particular attention is paid to the personal neutron dosimeter developed and routinely used by National Personal Dosimetry Service Ltd. in the Czech Republic. (author)

  11. Thermoluminescence albedo-neutron dosimetry

    International Nuclear Information System (INIS)

    Strand, T.; Storruste, A.

    1986-10-01

    The report discusses neutron detection with respect to dosimetry and compares different thermoluminescent dosimetry materials for neutron dosimetry. Construction and calibration of a thermoluminescence albedo neutron dosemeter, developed by the authors, is described

  12. Thermoluminescence in medical dosimetry

    International Nuclear Information System (INIS)

    Rivera, T.

    2011-10-01

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  13. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  14. Recent research into thermoluminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, T [National Inst. of Radiological Sciences, Chiba (Japan)

    1979-04-01

    The trend of basic research in thermoluminescent dosimetry (TLD), the results, and developing fields in which it can be applied are reported. This trend is outlined from the viewpoint fields of application, a new trend in TLD readers, the conditions of development of new photogenic substances, and research in the radiation characteristics of photogenic substances (radiosensitivity to particle rays and ultraviolet rays, dose rate dependence, temperature dependence at irradiation, and ..gamma.. ray energy dependence). Utilization of TLD in the medical field for measurement of environmental radiation and as a monitor for workers exposed to radiation is discussed. An international comparison of dose was necessary in order to prove its universal validity.

  15. Internal sources dosimetry

    International Nuclear Information System (INIS)

    Savio, Eduardo

    1994-01-01

    The absorbed dose, need of estimation in risk evaluation in the application of radiopharmaceuticals in Nuclear Medicine practice,internal dosimetry,internal and external sources. Calculation methodology,Marinelli model,MIRD system for absorbed dose calculation based on biological parameters of radiopharmaceutical in human body or individual,energy of emitted radiations by administered radionuclide, fraction of emitted energy that is absorbed by target body.Limitation of the MIRD calculation model. A explanation of Marinelli method of dosimetry calculation,β dosimetry. Y dosimetry, effective dose, calculation in organs and tissues, examples. Bibliography .

  16. Surface-seeking radionuclides in the skeleton: current approach and recent developments in biokinetic modelling for humans and beagles

    International Nuclear Information System (INIS)

    Luciani, A.; Polig, E.

    2007-01-01

    In the last decade, the biokinetics of surface-seeking radionuclides in the skeleton has been the object of several studies. Investigations were carried out to determine the kinetics of plutonium and americium in the skeleton of humans and beagles. As a result of these investigations, in recent years the models presented by ICRP in Publication 67 for humans were partially revised, particularly the skeletal part. The aim of the present work is to present recent developments in the biokinetic modelling of surface-seeking radionuclides (plutonium and americium) in beagles and humans. Various assumptions and physiological interpretations of the different approaches to the biokinetic modelling of the skeleton are discussed. Current ICRP concepts and skeleton modelling of plutonium and americium in humans are compared to the latest developments in biokinetic modelling in beagles. (authors)

  17. Neutron dosimetry: problems, solutions, prospects and the role of trace detectors

    International Nuclear Information System (INIS)

    Fernandez, F.

    2009-10-01

    It is present in schematic way, the origin of the neutrons; their interaction with matter, until its application in the field of dosimetry. It describes some measuring instruments based on thermoluminescence dosimetry, some activation detectors and trace detectors. Finally, it summarizes the work in neutron dosimetry have been carried out at the Autonomous University of Barcelona. (Author)

  18. The Vinca dosimetry experiment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1962-03-15

    On 15 October 1958 there occurred a very brief uncontrolled run of the zero-power reactor at the Boris Kidric Institute of Nuclear Science, Vinca, near Belgrade, Yugoslavia. During this run six persons received various doses of radiation. They were subsequently given medical treatment of a novel kind at the Curie Hospital, Paris. In atomic energy operations to date, very few accidents involving excessive radiation exposure to human beings have occurred. In fact, the cases of acute radiation injury are limited to about 30 known high exposures, few of which were in the lethal or near-lethal range. Since direct experiment to determine the effects of ionizing radiation on man is unacceptable, information on these effects has to be based on a consideration of data relating to accidental exposures, viewed in the light of the much more extensive data obtained from experiments on animals. Therefore, any direct information on the effects of radiation on humans is very valuable. The international dosimetry project described in this report was carried out at Vinca, Yugoslavia, under the auspices of the International Atomic Energy Agency to determine the precise amount of radiation to which the persons had been exposed during the accident. These dosimetry data, together with the record of the carefully observed clinical effects, are of importance both for the scientific study of radiation effects on man and for the development of methods of therapy. The experiment and measurements were carried out at the end of April 1960. The project formed part of the Agency's research programme in the field of health and safety. The results of the experiment are made available through this report to all Member States.

  19. The Vinca dosimetry experiment

    International Nuclear Information System (INIS)

    1962-03-01

    On 15 October 1958 there occurred a very brief uncontrolled run of the zero-power reactor at the Boris Kidric Institute of Nuclear Science, Vinca, near Belgrade, Yugoslavia. During this run six persons received various doses of radiation. They were subsequently given medical treatment of a novel kind at the Curie Hospital, Paris. In atomic energy operations to date, very few accidents involving excessive radiation exposure to human beings have occurred. In fact, the cases of acute radiation injury are limited to about 30 known high exposures, few of which were in the lethal or near-lethal range. Since direct experiment to determine the effects of ionizing radiation on man is unacceptable, information on these effects has to be based on a consideration of data relating to accidental exposures, viewed in the light of the much more extensive data obtained from experiments on animals. Therefore, any direct information on the effects of radiation on humans is very valuable. The international dosimetry project described in this report was carried out at Vinca, Yugoslavia, under the auspices of the International Atomic Energy Agency to determine the precise amount of radiation to which the persons had been exposed during the accident. These dosimetry data, together with the record of the carefully observed clinical effects, are of importance both for the scientific study of radiation effects on man and for the development of methods of therapy. The experiment and measurements were carried out at the end of April 1960. The project formed part of the Agency's research programme in the field of health and safety. The results of the experiment are made available through this report to all Member States

  20. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G [Department of Physics of the University and INFN, Milan (Italy)

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  1. Relative dosimetry by Ebt-3

    International Nuclear Information System (INIS)

    De Leon A, M. A.; Rivera M, T.; Hernandez O, J. O.

    2015-10-01

    In the present work relative dosimetry in two linear accelerator for radiation therapy was studied. Both Varian Oncology systems named Varian Clinac 2100-Cd and MLC Varian Clinac i X were used. Gaf Chromic Ebt-3 film was used. Measurements have been performed in a water equivalent phantom, using 6 MV and 18 MV photon beams on both Linacs. Both calibration and Electron irradiations were carried out with the ionization chamber placed at the isocenter, below a stack of solid water slabs, at the depth of dose maximum (D max), with a Source-to-Surface Distance (SSD) of 100 cm and a field size of 10 cm x 10 cm. Calibration and dosimetric measurements photons were carried out under IAEA-TRS 398 protocol. Results of relative dosimetry in the present work are discussed. (Author)

  2. Design and experimental testing of air slab caps which convert commercial electron diodes into dual purpose, correction-free diodes for small field dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Charles, P. H., E-mail: paulcharles111@gmail.com [Department of Radiation Oncology, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, Queensland 4102, Australia and School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001 (Australia); Cranmer-Sargison, G. [Department of Medical Physics, Saskatchewan Cancer Agency, 20 Campus Drive, Saskatoon, Saskatchewan S7L 3P6, Canada and College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5 (Canada); Thwaites, D. I. [Institute of Medical Physics, School of Physics, University of Sydney, New South Wales 2006 (Australia); Kairn, T. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia and Genesis CancerCare Queensland, The Wesley Medical Centre, Suite 1, 40 Chasely Street, Auchenflower, Brisbane, Queensland 4066 (Australia); Crowe, S. B.; Langton, C. M.; Trapp, J. V. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001 (Australia); Pedrazzini, G. [Genesis CancerCare Queensland, The Wesley Medical Centre, Suite 1, 40 Chasely Street, Auchenflower, Brisbane, Queensland 4066 (Australia); Aland, T.; Kenny, J. [Epworth Radiation Oncology, 89 Bridge Road, Richmond, Melbourne, Victoria 3121 (Australia)

    2014-10-15

    Purpose: Two diodes which do not require correction factors for small field relative output measurements are designed and validated using experimental methodology. This was achieved by adding an air layer above the active volume of the diode detectors, which canceled out the increase in response of the diodes in small fields relative to standard field sizes. Methods: Due to the increased density of silicon and other components within a diode, additional electrons are created. In very small fields, a very small air gap acts as an effective filter of electrons with a high angle of incidence. The aim was to design a diode that balanced these perturbations to give a response similar to a water-only geometry. Three thicknesses of air were placed at the proximal end of a PTW 60017 electron diode (PTWe) using an adjustable “air cap”. A set of output ratios (OR{sub Det}{sup f{sub c}{sub l}{sub i}{sub n}}) for square field sizes of side length down to 5 mm was measured using each air thickness and compared to OR{sub Det}{sup f{sub c}{sub l}{sub i}{sub n}} measured using an IBA stereotactic field diode (SFD). k{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}} was transferred from the SFD to the PTWe diode and plotted as a function of air gap thickness for each field size. This enabled the optimal air gap thickness to be obtained by observing which thickness of air was required such that k{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r}}}}}}}}} was equal to 1.00 at all field sizes. A similar procedure was used to find the optimal air thickness required to make a modified Sun Nuclear EDGE detector (EDGEe) which is “correction-free” in small field relative dosimetry. In addition, the feasibility of experimentally transferring k{sub Q{sub c{sub l{sub i{sub n,Q{sub m{sub s{sub r}{sup f{sub c}{sub l}{sub i}{sub n},f{sub m}{sub s}{sub r

  3. A quantitative evaluation of multiple biokinetic models using an assembled water phantom: A feasibility study.

    Directory of Open Access Journals (Sweden)

    Da-Ming Yeh

    Full Text Available This study examined the feasibility of quantitatively evaluating multiple biokinetic models and established the validity of the different compartment models using an assembled water phantom. Most commercialized phantoms are made to survey the imaging system since this is essential to increase the diagnostic accuracy for quality assurance. In contrast, few customized phantoms are specifically made to represent multi-compartment biokinetic models. This is because the complicated calculations as defined to solve the biokinetic models and the time-consuming verifications of the obtained solutions are impeded greatly the progress over the past decade. Nevertheless, in this work, five biokinetic models were separately defined by five groups of simultaneous differential equations to obtain the time-dependent radioactive concentration changes inside the water phantom. The water phantom was assembled by seven acrylic boxes in four different sizes, and the boxes were linked to varying combinations of hoses to signify the multiple biokinetic models from the biomedical perspective. The boxes that were connected by hoses were then regarded as a closed water loop with only one infusion and drain. 129.1±24.2 MBq of Tc-99m labeled methylene diphosphonate (MDP solution was thoroughly infused into the water boxes before gamma scanning; then the water was replaced with de-ionized water to simulate the biological removal rate among the boxes. The water was driven by an automatic infusion pump at 6.7 c.c./min, while the biological half-life of the four different-sized boxes (64, 144, 252, and 612 c.c. was 4.8, 10.7, 18.8, and 45.5 min, respectively. The five models of derived time-dependent concentrations for the boxes were estimated either by a self-developed program run in MATLAB or by scanning via a gamma camera facility. Either agreement or disagreement between the practical scanning and the theoretical prediction in five models was thoroughly discussed. The

  4. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1982-01-01

    The measurement of neutron exposures to personnel is an issue that has received increased attention in the last few years. It is important to consider key aspects of the whole dosimetry system when developing dose estimates. This begins with selection of proper dosimeters and survey instruments, and extends through the calibration methods. One must match the spectral response and sensitivity of the dosimeter to the spectral characteristics of the neutron fields. Threshold detectors that are insensitive to large fractions of neutrons in the lower energy portion of reactor spectra should be avoided. Use of two or more detectors with responses that complement each other will improve measurement quality. It is important to understand the spectral response of survey instruments, so that spectra which result in significant overresponse do not lead to overestimation of dose. Calibration sources that do not match operational field spectra can contribute to highly erroneous results. In those situations, in-field calibration techniques should be employed. Although some detection developments have been made in recent years, a lot can be done with existing technology until fully satisfactory, long term solutions are obtained

  5. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Xu Zhiyong

    2002-01-01

    Radiochromic film dosimetry was developed to measure ionization irradiation dose for industry and medicine. At this time, there are no comprehensive guideline on the medical application, calibration method and densitometer system for medicine. The review gives update on Radiochromic film dosimetry used for medicine, including principles, film model and material, characteristics, calibration method, scanning densitometer system and medical application

  6. Nuclear accident dosimetry

    International Nuclear Information System (INIS)

    1982-01-01

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  7. Personal dosimetry in Kazakhstan

    International Nuclear Information System (INIS)

    Khvoshnyanskaya, I.R.; Vdovichenko, V.G.; Lozbin, A.Yu.

    2003-01-01

    KATEP-AE Radiation Laboratory is the first organization in Kazakhstan officially licensed by the Kazakhstan Atomic Energy Committee to provide individual dosimetry services. The Laboratory was established according to the international standards. Nowadays it is the largest company providing personal dosimetry services in the Republic of Kazakhstan. (author)

  8. Nuclear accident dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-12-31

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  9. Human biodistribution and radiation dosimetry of 82Rb.

    Science.gov (United States)

    Senthamizhchelvan, Srinivasan; Bravo, Paco E; Esaias, Caroline; Lodge, Martin A; Merrill, Jennifer; Hobbs, Robert F; Sgouros, George; Bengel, Frank M

    2010-10-01

    Prior estimates of radiation-absorbed doses from (82)Rb, a frequently used PET perfusion tracer, yielded discrepant results. We reevaluated (82)Rb dosimetry using human in vivo biokinetic measurements. Ten healthy volunteers underwent dynamic PET/CT (6 contiguous table positions, each with separate (82)Rb infusion). Source organ volumes of interest were delineated on the CT images and transferred to the PET images to obtain time-integrated activity coefficients. Radiation doses were estimated using OLINDA/EXM 1.0. The highest mean absorbed organ doses (μGy/MBq) were observed for the kidneys (5.81), heart wall (3.86), and lungs (2.96). Mean effective doses were 1.11 ± 0.22 and 1.26 ± 0.20 μSv/MBq using the tissue-weighting factors of the International Commission on Radiological Protection (ICRP), publications 60 and 103, respectively. Our current (82)Rb dosimetry suggests reasonably low radiation exposure. On the basis of this study, a clinical (82)Rb injection of 2 × 1,480 MBq (80 mCi) would result in a mean effective dose of 3.7 mSv using the weighting factors of the ICRP 103-only slightly above the average annual natural background exposure in the United States (3.1 mSv).

  10. Optimization of radiation protection in nuclear medicine: from reference dosimetry to personalized dosimetry

    International Nuclear Information System (INIS)

    Hadid, Lama

    2011-01-01

    In nuclear medicine, radiopharmaceuticals are distributed in the body through biokinetic processes. Thus, each organ can become a source of radiation delivering a fraction of emitted energy in tissues. Therefore, dose calculations must be assessed accurately and realistically to ensure the patient radiation protection. Absorbed doses were until now based on mathematical standard models and electron transport approximations. The International Commission on Radiological Protection (ICRP) has recently adopted voxel phantoms as a more realistic representation of the reference adult. The main goal of this thesis was to study the influence of the use of the new reference models and Monte Carlo methods on the major dosimetric quantities. In addition, the contribution of patients? specific geometry to the absorbed dose was compared to a standard geometry, enabling the evaluation of uncertainties arising from the reference values. Particular attention was paid to the bone marrow which is characterized by a high radiosensitivity and a complex microscopic structure. An accurate alpha dosimetry was assessed for bone marrow using microscopic images of several trabecular bone sites. The results showed variations in the absorbed fractions as a function of the particles? energy, the skeletal site and the amount of fat within marrow cavities, three parameters which are not taken into account in the values published by the ICRP. Finally, the heterogeneous activity distribution of the radiopharmaceuticals was considered within the framework of the treatment of a hepato-cellular carcinoma with selective internal radiotherapy using Yttrium-90 through the analysis of dose-volume histograms. The developments made in this thesis show the importance and the feasibility of performing a personalized dosimetry for nuclear medicine patients. (author)

  11. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Boyd, A.W.; Chadwick, K.H.; McDonald, J.C.; Miller, A.

    1989-01-01

    Radiation processing is a relatively young industry with broad applications and considerable commercial success. Dosimetry provides an independent and effective way of developing and controlling many industrial processes. In the sterilization of medical devices and in food irradiation, where the radiation treatment impacts directly on public health, the measurements of dose provide the official means of regulating and approving its use. In this respect, dosimetry provides the operator with a means of characterizing the facility, of proving that products are treated within acceptable dose limits and of controlling the routine operation. This book presents an up-to-date review of the theory, data and measurement techniques for radiation processing dosimetry in a practical and useful way. It is hoped that this book will lead to improved measurement procedures, more accurate and precise dosimetry and a greater appreciation of the necessity of dosimetry for radiation processing. (author)

  12. Neutron-photon mixed field dosimetry by TLD-700 glow curve analysis and its implementation in dose monitoring for Boron Neutron Capture Therapy (BNCT) treatments

    Energy Technology Data Exchange (ETDEWEB)

    Boggio, E. F.; Longhino, J. M. [Centro Atomico Bariloche, Departamento de Fisica de Reactores y Radiaciones / CNEA, Av. E. Bustillo Km 9.5, R8402AGP San Carlos de Bariloche (Argentina); Andres, P. A., E-mail: efboggio@cab.cnea.gov.ar [Centro Atomico Bariloche, Division Proteccion Radiologica / CNEA, Av. E. Bustillo Km 9.5, R8402AGP San Carlos de Bariloche (Argentina)

    2015-10-15

    BNCT is a cancerous cells selective, non-conventional radiotherapy modality to treat malignant tumors such as glioblastoma, melanoma and recurrent head and neck cancer. It consists of a two-step procedure: first, the patient is injected with a tumor localizing drug containing a non-radioactive isotope (Boron-10) with high slow neutron capture cross-section. In a second step, the patient is irradiated with neutrons, which are absorbed by the Boron-10 agent with the subsequently nuclear reaction B- 10(n,a)Li-7, thereby resulting in dose at cellular level due to the high-Let particles. The neutron fields suitable for BNCT are characterized by high neutron fluxes and low gamma dose. Determination of each component is not an easy task, especially when the volume of measurement is quite small or inaccessible for a miniature ionization chamber, for example. A method of measuring the photon and slow neutron dose(mainly by N-14 and B-10) from the glow curve (GC) analysis of a single {sup 7}LiF thermoluminescence detector is evaluated. This method was suggested by the group headed by Dr. Grazia Gambarini. The dosemeters used were TLD-600 ({sup 6}LiF:Mg,Ti with 95.6% {sup 6}Li) and TLD-700 ({sup 7}LiF:Mg,Ti with 99.9% {sup 7}LiF) from Harshaw. Photon dose measurement using the GC analysis method with TLD-700 in mixed fields requires the relation of the two main peaks of a TLD-600 GC shape obtained from an exposition to the same neutron field, and a photon calibrated GC with TLD-700. The requirements for slow neutron dose measurements are similar. In order to properly apply the GC analysis method at the Ra-6 Research Reactor BNCT facility, measurements were carried out in a standard water phantom, fully characterized on the BNCT beam by conventional techniques (activation detectors and paired ionization chambers technique). Next, the method was implemented in whole body dose monitoring of a patient undergoing a BNCT treatment, using a Bo MAb (Bottle Manikin Absorption) phantom

  13. 5th symposium on neutron dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Spurny, F

    1985-03-01

    The symposium was held in Neuherberg near Munich on September 17-20, 1984 and was attended by 200 specialists from 20 coutries. The participants discussed the following areas of neutron dosimetry: basic concept and analysis of irradiation, basic data, proportional counters in radiation protection, detector response and spectrometry, enviromental monitoring, radiobiology and biophysical models, analysis of neutron fields, thermoluminescent detectors, personnel monitoring, calibration, measurement in the environment of /sup 252/Cf sources, analysis of fields and detector response, standardization dosimetry, ionization chambers, planning of therapeutical irradiation study of depth dose distribution, facilities for neutron therapy and international comparison. (E.S.).

  14. 5th symposium on neutron dosimetry

    International Nuclear Information System (INIS)

    Spurny, F.

    1985-01-01

    The symposium was held in Neuherberg near Munich on September 17-20, 1984 and was attended by 200 specialists from 20 coutries. The participants discussed the following areas of neutron dosimetry: basic concept and analysis of irradiation, basic data, proportional counters in radiation protection, detector response and spectrometry, enviromental monitoring, radiobiology and biophysical models, analysis of neutron fields, thermoluminescent detectors, personnel monitoring, calibration, measurement in the environment of 252 Cf sources, analysis of fields and detector response, standardization dosimetry, ionization chambers, planning of therapeutical irradiation study of depth dose distribution, facilities for neutron therapy and international comparison. (E.S.)

  15. An empirical multivariate log-normal distribution representing uncertainty of biokinetic parameters for 137Cs

    International Nuclear Information System (INIS)

    Miller, G.; Martz, H.; Bertelli, L.; Melo, D.

    2008-01-01

    A simplified biokinetic model for 137 Cs has six parameters representing transfer of material to and from various compartments. Using a Bayesian analysis, the joint probability distribution of these six parameters is determined empirically for two cases with quite a lot of bioassay data. The distribution is found to be a multivariate log-normal. Correlations between different parameters are obtained. The method utilises a fairly large number of pre-determined forward biokinetic calculations, whose results are stored in interpolation tables. Four different methods to sample the multidimensional parameter space with a limited number of samples are investigated: random, stratified, Latin Hypercube sampling with a uniform distribution of parameters and importance sampling using a lognormal distribution that approximates the posterior distribution. The importance sampling method gives much smaller sampling uncertainty. No sampling method-dependent differences are perceptible for the uniform distribution methods. (authors)

  16. Cellular dosimetry

    International Nuclear Information System (INIS)

    Humm, J.L.; Chin, L.M.

    1989-01-01

    Radiation dose is a useful predictive parameter for describing radiation toxicity in conventional radiotherapy. Traditionally, in vitro radiation biology dose-effect relations are expressed in the form of cell survival curves, a semilog plot of cell survival versus dose. However, the characteristic linear or linear quadratic survival curve shape, for high- and low-LET radiations respectively, is only strictly valid when the radiation dose is uniform across the entire target population. With an external beam of 60 Co gamma rays or x-rays, a uniform field may be readily achievable. When radionuclides are incorporated into a cell milieu, several new problems emerge which can result in a departure from uniformity in energy deposition throughout a cell population. This nonuniformity can have very important consequences for the shape of the survival curve. Cases in which perturbations of source uniformity may arise include: 1. Elemental sources may equilibrate in the cell medium with partition coefficients between the extracellular, cytosol, and nuclear compartments. The effect of preferential cell internalization or binding to cell membrane of some radionuclides can increase or decrease the slope of the survival curve. 2. Radionuclides bound to antibodies, hormones, metabolite precursors, etc., may result in a source localization pattern characteristic of the carrier agent, i.e., the sources may bind to cell surface receptors or antigens, be internalized, bind to secreted antigen concentrated around a fraction of the cell population, or become directly incorporated into the cell DNA. We propose to relate the distribution of energy deposition in cell nuclei to biological correlates of cellular inactivation. The probability of each cell's survival is weighted by its individual radiation burden, and the summation of these probabilities for the cell population can be used to predict the number or fraction of cell survivors

  17. EPR dosimetry - present and future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as co-ordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as biomarkers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (ASTM), and the International Organisation of Standards (ISO) as well as those of the International Commission on Radiation Units and Measurements (ICRU) considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (author)

  18. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Regulla, D.F. [GSF - National Research Centre for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg (Germany)

    1999-07-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  19. EPR Dosimetry - Present and Future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  20. Uncertainty and sensitivity analysis of biokinetic models for radiopharmaceuticals used in nuclear medicine

    International Nuclear Information System (INIS)

    Li, W. B.; Hoeschen, C.

    2010-01-01

    Mathematical models for kinetics of radiopharmaceuticals in humans were developed and are used to estimate the radiation absorbed dose for patients in nuclear medicine by the International Commission on Radiological Protection and the Medical Internal Radiation Dose (MIRD) Committee. However, due to the fact that the residence times used were derived from different subjects, partially even with different ethnic backgrounds, a large variation in the model parameters propagates to a high uncertainty of the dose estimation. In this work, a method was developed for analysing the uncertainty and sensitivity of biokinetic models that are used to calculate the residence times. The biokinetic model of 18 F-FDG (FDG) developed by the MIRD Committee was analysed by this developed method. The sources of uncertainty of all model parameters were evaluated based on the experiments. The Latin hypercube sampling technique was used to sample the parameters for model input. Kinetic modelling of FDG in humans was performed. Sensitivity of model parameters was indicated by combining the model input and output, using regression and partial correlation analysis. The transfer rate parameter of plasma to other tissue fast is the parameter with the greatest influence on the residence time of plasma. Optimisation of biokinetic data acquisition in the clinical practice by exploitation of the sensitivity of model parameters obtained in this study is discussed. (authors)

  1. Mechanism of cisplatin proximal tubule toxicity revealed by integrating transcriptomics, proteomics, metabolomics and biokinetics.

    Science.gov (United States)

    Wilmes, Anja; Bielow, Chris; Ranninger, Christina; Bellwon, Patricia; Aschauer, Lydia; Limonciel, Alice; Chassaigne, Hubert; Kristl, Theresa; Aiche, Stephan; Huber, Christian G; Guillou, Claude; Hewitt, Philipp; Leonard, Martin O; Dekant, Wolfgang; Bois, Frederic; Jennings, Paul

    2015-12-25

    Cisplatin is one of the most widely used chemotherapeutic agents for the treatment of solid tumours. The major dose-limiting factor is nephrotoxicity, in particular in the proximal tubule. Here, we use an integrated omics approach, including transcriptomics, proteomics and metabolomics coupled to biokinetics to identify cell stress response pathways induced by cisplatin. The human renal proximal tubular cell line RPTEC/TERT1 was treated with sub-cytotoxic concentrations of cisplatin (0.5 and 2 μM) in a daily repeat dose treating regime for up to 14 days. Biokinetic analysis showed that cisplatin was taken up from the basolateral compartment, transported to the apical compartment, and accumulated in cells over time. This is in line with basolateral uptake of cisplatin via organic cation transporter 2 and bioactivation via gamma-glutamyl transpeptidase located on the apical side of proximal tubular cells. Cisplatin affected several pathways including, p53 signalling, Nrf2 mediated oxidative stress response, mitochondrial processes, mTOR and AMPK signalling. In addition, we identified novel pathways changed by cisplatin, including eIF2 signalling, actin nucleation via the ARP/WASP complex and regulation of cell polarization. In conclusion, using an integrated omic approach together with biokinetics we have identified both novel and established mechanisms of cisplatin toxicity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baldock, C [Institute of Medical Physics, School of Physics, University of Sydney (Australia); De Deene, Y [Radiotherapy and Nuclear Medicine, Ghent University Hospital (Belgium); Doran, S [CRUK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Surrey (United Kingdom); Ibbott, G [Radiation Physics, UT M D Anderson Cancer Center, Houston, TX (United States); Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Lepage, M [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et de radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); McAuley, K B [Department of Chemical Engineering, Queen' s University, Kingston, ON (Canada); Oldham, M [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Schreiner, L J [Cancer Centre of South Eastern Ontario, Kingston, ON (Canada)], E-mail: c.baldock@physics.usyd.edu.au, E-mail: yves.dedeene@ugent.be

    2010-03-07

    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. (topical review)

  3. Biokinetic and dosimetry of 99mTc-14F7-monoclonal antibody in patients with breast cancer

    International Nuclear Information System (INIS)

    Gonzalez, Joaquin; Calderon, Carlos; Pimentel, Gilmara; Oliva, Juan P.; Casaco, Angel

    2008-01-01

    Full text: The 14F7 murine MAb is an IgG1 that binds specifically to GM3(Neu-Gc) ganglioside strongly recognizing the antigen displayed in human breast and melanoma tumors. A preliminary report showed in vivo evidences of presence of GM3(Neu-Gc) ganglioside in human breast primary tumors using 14F7 MAb labelled with 99m Tc. In this work the pharmacokinetics and biodistribution of 99m Tc-14F7 MAb in patient with breast cancer were studied. The absorbed dose in normal organ and tumors was also calculated. The patients were selected from a Phase I/II clinical trial which included 14 female patients with cytological diagnose of breast carcinoma in stage II without previous onco-specific treatment. Three groups were conformed: Group I (0.3mg, n=5), Group II (1mg, n=5) and Group III (3mg, n=4). The activity ranged in 1.11 - 1.48GBq (30- 40mCi) was intravenously administered during 1-2min. The 99m Tc-14F7 plasma clearance was determined by blood sampling at 5, 10, 20, 30min and 1, 2, 4, 8 and 24h after injection. All urine excreted by patients was collected during 24h after injection at intervals of 0-2h, 2-8h and 8-24h. Prior to injection, a transmission scan of head, thorax, abdomen and pelvis was obtained using a 57 Co flood source. Anterior and posterior whole body images were acquired at 30min, 2h, 4h, 8h and 24h after injection using a Gamma Camera (SophyCamera DS7) with pinhole collimator. Static anterior and posterior images were obtained from head, thorax, abdomen, pelvis and lateral images of each breast in pendular position at 2h, 4h, 8h and 24h. Internal absorbed dose calculation was performed according to MIRD formalism using the S values for adult non-pregnant female phantom downloaded from the RADAR website. Self-absorbed tumor dose were calculated assuming those as spheres with uniform distribution of activity. The plasma clearance of radiotracer in all groups shows a monoexponential decay behaviour with biological elimination half time ranged in 15h and 19h. The distribution volume was similar to physiological volume in normal subject. A low urinary excretion was observed. The biodistribution shows a high retention of radiotracer in whole-body. A high uptake and retention was observed in bone marrow, kidneys and liver. The highest absorbed dose per MBq was observed in liver and kidneys. The 99m Tc-14F7 shows a rapid tumor uptake (<2.5h) with a delayed biological elimination half time (>4.5 days). In most cases, the maximum activity uptake in tumor (<1%/100g of tumor) was observed at 24 hours after injection. The pharmacokinetic data observed for 99m Tc-14F7 MAb behaves as a monoexponential model showing a slow clearance from plasma and a low urinary excretion. (author)

  4. Biokinetic and dosimetry of {sup 99m}Tc-14F7-monoclonal antibody in patients with breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Joaquin; Calderon, Carlos; Pimentel, Gilmara; Oliva, Juan P., E-mail: jgg@infomed.sld.cu [Departmento de Medicina Nuclear, Instituto de Oncologia y Radiobiologia, Cidad Habana (Cuba); Casaco, Angel [Division de Ensayos Clinicos, Centro de Inmunologia Molecular, Reparto Siboney, Ciudad Habana (Cuba)

    2008-07-01

    Full text: The 14F7 murine MAb is an IgG1 that binds specifically to GM3(Neu-Gc) ganglioside strongly recognizing the antigen displayed in human breast and melanoma tumors. A preliminary report showed in vivo evidences of presence of GM3(Neu-Gc) ganglioside in human breast primary tumors using 14F7 MAb labelled with {sup 99m}Tc. In this work the pharmacokinetics and biodistribution of {sup 99m}Tc-14F7 MAb in patient with breast cancer were studied. The absorbed dose in normal organ and tumors was also calculated. The patients were selected from a Phase I/II clinical trial which included 14 female patients with cytological diagnose of breast carcinoma in stage II without previous onco-specific treatment. Three groups were conformed: Group I (0.3mg, n=5), Group II (1mg, n=5) and Group III (3mg, n=4). The activity ranged in 1.11 - 1.48GBq (30- 40mCi) was intravenously administered during 1-2min. The {sup 99m}Tc-14F7 plasma clearance was determined by blood sampling at 5, 10, 20, 30min and 1, 2, 4, 8 and 24h after injection. All urine excreted by patients was collected during 24h after injection at intervals of 0-2h, 2-8h and 8-24h. Prior to injection, a transmission scan of head, thorax, abdomen and pelvis was obtained using a {sup 57}Co flood source. Anterior and posterior whole body images were acquired at 30min, 2h, 4h, 8h and 24h after injection using a Gamma Camera (SophyCamera DS7) with pinhole collimator. Static anterior and posterior images were obtained from head, thorax, abdomen, pelvis and lateral images of each breast in pendular position at 2h, 4h, 8h and 24h. Internal absorbed dose calculation was performed according to MIRD formalism using the S values for adult non-pregnant female phantom downloaded from the RADAR website. Self-absorbed tumor dose were calculated assuming those as spheres with uniform distribution of activity. The plasma clearance of radiotracer in all groups shows a monoexponential decay behaviour with biological elimination half time ranged in 15h and 19h. The distribution volume was similar to physiological volume in normal subject. A low urinary excretion was observed. The biodistribution shows a high retention of radiotracer in whole-body. A high uptake and retention was observed in bone marrow, kidneys and liver. The highest absorbed dose per MBq was observed in liver and kidneys. The {sup 99m}Tc-14F7 shows a rapid tumor uptake (<2.5h) with a delayed biological elimination half time (>4.5 days). In most cases, the maximum activity uptake in tumor (<1%/100g of tumor) was observed at 24 hours after injection. The pharmacokinetic data observed for {sup 99m}Tc-14F7 MAb behaves as a monoexponential model showing a slow clearance from plasma and a low urinary excretion. (author)

  5. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both by international organizations (IAEA) and national laboratories have helped to improve the reliability of dose measurements. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading to traceable and reliable dosimetry are discussed. (author)

  6. Dosimetry and operation of irradiation facilities

    International Nuclear Information System (INIS)

    Vidal, P.E.

    1985-01-01

    The industrial use of ionizing radiation has required, from the very first, the measurement of delivered and absorbed doses; hence the necessity of providing dosimetric systems. Laboratories, scientists, industries and potential equipment manufacturers have all collaborated in this new field of activity. Dosimetric intercomparisons have been made by each industry at their own facilities and in collaboration with specialists, national organizations and the IAEA. Dosimetry has become a way of ensuring that treatment by irradiation has been carried out in accordance with the rules. It has become in effect assurance of quality. Routine dosimetry should determine a maximum and minimum dose. Numerous factors play a part in dosimetry. Industry is currently in possession of routine dosimetric systems that are sufficiently accurate, fairly easy to handle and reasonable in cost, thereby satisfying all the requirements of industry and the need for control. Dosimetry is important in the process of marketing irradiated products. The operator of an industrial irradiation facility bases his dosimetry on comparison with reference systems. Research aimed at simplifying the practice of routine dosimetry should be continued. New physical and chemical techniques will be incorporated into systems already in use. The introduction of microcomputers into the operation of radiation facilities has increased the value of dosimetry and made the conditions of treatment more widespread. Stress should be placed on research in several areas apart from reference systems, for example: dosimetric systems at temperatures from +8 deg. C to -45 deg. C, over the dose range 100 krad to a little more than 1 Mrad, liquids and fluidized solids carried at high speed through ducts, thin-film liquids circulating at a high flow rate, and various other problems. (author)

  7. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    shapes and sizes while sparing normal tissue. The situation is further complicated if the normal tissues are critical organs or are particularly sensitive to radiation. Radiotherapy techniques employed to obtain a closer conformation of the dose distribution to the tumour volume are referred to as conformal radiotherapy techniques. The clinical implementation of conformal therapy has been delayed by limitations in the verification of conformal dose distributions calculated by treatment planning systems prior to the irradiation of the patient and the verification of complex treatments during its delivery to the patient. There are several aspects of conformal therapy that complicate dose verification. To achieve the dose distributions conforming to complex 3D volumes, high dose gradients arise in the treatment volume. Further, overdose or underdose regions can exist when separate radiation fields are used to deliver additional radiation. These aspects require that practical dose measurement (dosimetry) techniques be able to integrate dose over time and easily measure dose distributions in 3D with high spatial resolution. Traditional dosimeters, such as ion chambers, thermoluminescent dosimeters and radiographic film do not fulfil these requirements. Novel gel dosimetry techniques are being developed in which dose distributions can potentially be determined in vitro in 3D using anthropomorphic phantoms to simulate a clinically irradiated situation. As long ago as the 1950's, radiation-induced colour change in dyes was used to investigate radiation doses in gels. It was subsequently shown that radiation induced changes in nuclear magnetic resonance (NMR) relaxation properties of gels infused with conventional Fricke dosimetry solutions could be measured using magnetic resonance imaging (MRI). In Fricke gels, Fe 2+ ions in ferrous sulphate solutions are usually dispersed throughout a gelatin, agarose or PVA matrix. Radiation-induced changes in the dosimeters are considered to

  8. Practical neutron dosimetry at high energies

    International Nuclear Information System (INIS)

    McCaslin, J.B.; Thomas, R.H.

    1980-10-01

    Dosimetry at high energy particle accelerators is discussed with emphasis on physical measurements which define the radiation environment and provide an immutable basis for the derivation of any quantities subsequently required for risk evaluation. Results of inter-laboratory dosimetric comparisons are reviewed and it is concluded that a well-supported systematic program is needed which would make possible detailed evaluations and inter-comparisons of instruments and techniques in well characterized high energy radiation fields. High-energy dosimetry is so coupled with radiation transport that it is clear their study should proceed concurrently

  9. Dosimetry of internal emitters

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The Dosimetry of Internal Emitter Program endeavors to refine the correlation between radiation dose and observed biological effects. The program is presently engaged in the development of studies that will demonstrate the applicability of microdosimetry models developed under the Microdosimetry of Internal Sources Program. The program also provides guidance and assistance to Pacific Northwest Laboratory's Biology Department in the dosimetric analysis of internally deposited radionuclides. This report deals with alpha particle dosimetry plutonium 239 inhalation, and in vitro studies of chromosomal observations

  10. Individual neutron dosimetry

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.

    1987-01-01

    The most important concepts and development in individual neutron dosimetry are presented, especially the dosimetric properties of the albedo technique. The main problem in albedo dosimetry is to calibrate the dosemeter in the environs of each neutron source. Some of the most used calibration techniques are discussed. The IRD albedo dosemeter used in the routine neutron individual monitoring is described in detail. Its dosimetric properties and calibration methods are discussed. (Author) [pt

  11. Historical note: thermoluminescent dosimetry (LiF) 1950-51

    International Nuclear Information System (INIS)

    Heckelsberg, L.F.

    1980-01-01

    The early history of thermoluminescent dosimetry has not been adequately described and one of the first workers in this field takes this opportunity to record more fully the history of the period. (author)

  12. Practical applications of the new ICRP recommendation to external dosimetry

    International Nuclear Information System (INIS)

    Kraus, W.

    1992-01-01

    Focussing on external dosimetry for occupational exposure the consequences of the new quantities equivalent dose (radiation weighting factor), effective dose (tissue weighting factor) and the ICRU operational quantities for individual and area dosimetry are discussed. Despite some arguments against the new quantities they should be introduced as rapidly as possible to keep international uniformity in radiation protection monitoring. It is shown that they provide a conservative estimate of the effective dose for photons and neutrons. In photon dosimetry only minor changes of the conversion factors relating operational quantities to effective dose is observed. In neutron dosimetry the conversion factors change by a factor of up to 2. It is pointed out that there is a urgent need to calculate standardized conversion factors for field quantities -operational quantities- organ and effective dose in a joint effort of ICRP and ICRU. This includes standardization of calibration methods for individual dosimetry using suitable phantoms instead of the sphere. (author)

  13. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1999-01-01

    The Dosimetry and Calibration Section fulfils two tasks within CERN's Radiation Protection Group: the Individual Dosimetry Service monitors more than 5000 persons potentially exposed to ionizing radiation on the CERN sites, and the Calibration Laboratory verifies throughout the year, at regular intervals, over 1000 instruments, monitors, and electronic dosimeters used by RP Group. The establishment of a Quality Assurance System for the Individual Dosimetry Service, a requirement of the new Swiss Ordinance for personal dosimetry, put a considerable workload on the section. Together with an external consultant it was decided to identify and then describe the different 'processes' of the routine work performed in the dosimetry service. The resulting Quality Manual was submitted to the Federal Office for Public Health in Bern in autumn. The CERN Individual Dosimetry Service will eventually be officially endorsed after a successful technical test in March 1999. On the technical side, the introduction of an automatic development machine for gamma films was very successful. It processes the dosimetric films without an operator being present, and its built-in regeneration mechanism keeps the concentration of the processing chemicals at a constant level

  14. Air kerma national standard of Russian Federation for x-ray and gamma radiation. Activity SSDL/VNIIM in medical radiation dosimetry field

    International Nuclear Information System (INIS)

    Kharitonov, I.A.; Villevalde, N.D.; Oborin, A.V.; Fominykh, V.I.

    2002-01-01

    for medium-energy X-ray range in 1998. The results of comparisons are presented in the table 1. Dimensions of unities of air kerma and air kerma rate are transmitted from primary standard to secondary standards with expanded uncertainty from 1,3 to 2,5 % (k=2), which are including and at laboratory SSDL/VNIIM and base dosimetry laboratory CNIRRI. The comparisons of secondary standards with the primary standard VNIIM are performed one time in 5 years. The laboratory SSDL/VNIIM is the component of state primary standards laboratory in the field of measurement ionizing radiations VNIIM. SSDL/VNIIM has the secondary standard - universal dosimeter UNIDOS with ionization chambers of volume from 0,6 cm 3 to 10 liters, radioactive sources from Fe-55, Cd-109, Am-241, Cs-137 and Co-60 with activity from 0,03 to 140 GBq. The primary standard equipment and facility on the basis industrial X-ray apparatus YRD-1 with a tungsten-anode X-ray tube and inherent filtration of around 3 mm Al (at generating potential from 50 to 250 kV) are used for calibration dosimetric devices in the field X-ray. There is termoluminescence dosimetric system such as KDT-02M with TL detectors from LiF for spending audit measurements by method 'dose-post'. Laboratory SSDL/VNIIM and base dosimetric laboratory CNIRRI are carried out calibrations and verifications of air kerma and air kerma rate reference standards and working measurement means for X-ray and gamma therapy and diagnostics, belonging to the oncology and diagnostic centers, clinics and hospitals. The laboratory CNIRRI fulfils the verification of measurement means and supervision of the application in the medical radiology, but the regional departments of radial diagnostics put into practice monitoring of doses, obtained by patients and staff at fulfilling of diagnostic and medical procedures. The diagnostic and clinical dosimeters are calibrated directly under the primary standard of air kerma and air kerma rate for achievement the highest

  15. Internal Dosimetry in therapy with 90Y

    International Nuclear Information System (INIS)

    Torres, Leonel; Vergara, Alex; García, Leonardo

    2016-01-01

    Introduction: 90 Y has shown satisfactory results in the therapy of multiple oncological diseases. This radionuclide has been widely used in therapy of diseases such as NHL (Zevalin), TNE ( 90 Y-DOTATOC), liver cancer, etc. Its safe and effective use presupposes the availability of accurate dosimetry methods and reproducible.El objective of this work is to standardize and optimize images use procedures that allow for dosimetric estimates braking during therapy of malignant diseases 90 Y. Materials and Methods: To quantify the activity in absolute units from scans correction methods that consider the peculiarities of the bremsstrahlung of 90 Y were proposed. acquisition parameters such as the selection of the collimator and the definition of energy windows as well as methods of scatter correction, attenuation, interactions of radiation with the collimator (septal penetration and degradation of information with distance) were considered and sensitivity or calibration factor was estimated. They were evaluated and calibrated parameters for dosimetry at the level of organ and estimates of distributions 3D dose, using experimental measurements with SPECT Mediso Nucline ™ Spirit DH-V system and simulations were performed using the Monte Carlo method, using the SIMIND v5 software .0. Results: The optimum position-energy window width and collimator to be used is determined from the relationship between total photons and primary photons (T / P), calculated with SIMIND. The results were favorable to employ HEGP collimator and energy window between 90-170kev. the sensitivity of the system for the selected collimator (HEGP for 90 Y) was estimated. He was evaluated and determined the MTF order to correct dispersive plane images, the source-detector and interactions of radiation with the collimator distance, using filtering methods (Wiener filter), including empirical estimates of the SNR component. Similarly the procedure for the use of transmission maps obtained from

  16. Course of training in Specific internal dosimetry for the patient

    International Nuclear Information System (INIS)

    Rojo, A.M.; Michelin, S.C.; Gomez P, I.M.

    2006-01-01

    In this work the experience obtained in a course organized in Argentina to qualify professionals in the radiopharmaceutical dosimetry using the methodology MIRD and the patient's images is presented. The motivation to carry out it was based on the continuous development of new radiopharmaceuticals with therapeutic purposes that makes necessary the knowledge of the distribution of the absorbed dose to be able to establish the dose-response relationship. The main objective was the study of the biokinetic model and those techniques available that starting from images can contribute information of specific parameters of the patient to calculate with more accuracy the doses in the tumor and in different organs. In the design of the program of this course it was considered to approach the different focuses for the calculation of specific dose of the patient and includes the following topics: the patient's radiological protection, new concepts in damages by radiations (bystander effect), methodology for the internal dosimetry by radiopharmaceuticals, dosimetric systems (MIRD/ICRP), revision of the physical phantoms, design of kinetic studies, compartmental models, calculation tools and the demonstration of the programs SAAM and OLINDA; calculation of activity starting from the patient's images (planar and SPECT). Principles of the gamma camera: the dispersed radiation, calculation of the activity with planar images, the attenuation, correction of the dispersed radiation, collimation problems. SPECT: the common method of reconstruction, basic principles, method of filtered over head projection and iterative methods (MLEM/OSEM), measurement of the attenuation maps, problems of the penetration in the collimator (I-131, I-123), effects of partial volume, incorporation of corrections in an iterative reconstruction. Dosimetry in bone marrow, discussion of study cases of new radiopharmaceuticals. Internal dosimetry in small scale for electrons and photons. Perspectives of the

  17. Blood doses and remnant biokinetics after thyroid ablation therapy of differentiated thyroid cancer: withdrawal vs. rh TSH

    International Nuclear Information System (INIS)

    Lassmann, Michael; Haenscheid, Heribert; Luster, Markus; Reiners, Christoph; Ablation, Trial Study Group

    2005-01-01

    Full text: An international randomized multicenter trial (9 sites; North America: 5, Europe: 4) was carried out investigating the effectiveness of ablation therapy with 3.7 GBq 131 I in differentiated thyroid cancer. We present the results of the trial dosimetry assessments. 63 patients were randomized after thyroidectomy to either hypothyroidism (THW) or euthyroidism in combination with rh TSH (0.9 mg q d x 2, Thyrogen). The biokinetics and residence times (RT) of the remnants were assessed from 3 neck scans starting 48 h after administration. The blood doses (a surrogate for the bone marrow dose) were calculated from activity concentrations in blood samples and 131 I whole body retention measurements between 2 and 168 h after 131 I administration. The overall dosimetry results were calculated centrally (Wuerzberg) in an externally audited standardized data evaluation procedure. The patient ablation rate was 100%. The 48 h 131 I uptake was lower in the remnant tissue of the rh TSH group: 0.5 ± 0.7%; THW group: 0.9 ±1.0% (p=0.1), the effective half life showed smaller values for the THW group (48.0 ± 52.6 h vs. 67.6 ± 48.9 h, p=0.0116). The mean RT in the remnant tissue was shorter in the rh TSH group: 0.9 ± 1.3 h; THW group: 1.4 ± 1.5 h (p=0.1). A greater decrease in the mean percentage of administered activity in the blood at 48 h, and a lower mean residence time was seen in the rh TSH group: 0.8%, RT: 2.3 ± 0.7 h; THW group: 1.8% (p=0.0011), RT: 3.5 ± 1.63 h (p=0.0004). The mean specific blood dose was significantly lower (p<0.0001) in the rh TSH group (0.072 ± 0.017 mGy/MBq, blood vessel radius (VR):0.2 mm; 0.104 ± 0.025 mGy/MBq, VR: 5 mm) than in the Hypothyroid group (0.106 ± 0.037 mGy/MBq, VR: 0.2 mm; 0.158 ± 0.059 mGy/MBq, VR: 5 mm). Conclusion: Although the remnant RT tended to be lower in the rh TSH group the ablation rates in the 2 study arms were comparable. The radiation dose to the blood was significantly lower in the rh TSH group. This

  18. Image in nuclear dosimetry using thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Guinsburg, G.; Matsuoka, M.; Watanabe, S.

    1987-01-01

    A low cost methodology to produce images of internal sick organs by radioisotopic intake, is presented. Dosimetries of thermoluminescent material and Teflon (ratio:50%) in bidimensional matrix shape are used with a Pb collimator. This collimator-bidimensional matrix system was tested ''in vivo'' and in thyroid phantoms using 99m Tc. A comparative evaluation between this method and the scintigraphy one is presented. (M.A.C.) [pt

  19. Improvements in the biokinetic model for strontium with allowance for age and gender differences in bone mineral metabolism

    International Nuclear Information System (INIS)

    Shagina, N.B.; Tolstykh, E.I.; Degteva, M.O.

    2003-01-01

    An age- and gender-dependent biokinetic model for strontium was developed based on the study of a population living along the Techa River exposed to effluents from the Mayak Production Association. To estimate parameters of a new model (Techa biokinetic model, TBM) many data sets have been assembled: our whole-body counter data on long-term retention of 90 Sr in humans, data from studies during the period of global fallout, data resulting from deliberate injections of strontium radionuclides, and non-radiological data regarding bone formation and resorption, mineral content of the body, etc. The model was developed using the basic structure of the ICRP biokinetic model for strontium, but new age- and gender-specific parameters were derived. This paper discusses the approaches applied to develop the new model. (author)

  20. Strontium biokinetic model for the pregnant woman and fetus: application to Techa River studies

    International Nuclear Information System (INIS)

    Shagina, N B; Tolstykh, E I; Degteva, M O; Fell, T P; Harrison, J D

    2015-01-01

    A biokinetic model for strontium (Sr) for the pregnant woman and fetus (Sr-PWF model) has been developed for use in the quantification of doses from internal radiation exposures following maternal ingestion of Sr radioisotopes before or during pregnancy. The model relates in particular to the population of the Techa River villages exposed to significant amounts of ingested Sr radioisotopes as a result of releases of liquid radioactive wastes from the Mayak plutonium production facility (Russia) in the early 1950s. The biokinetic model for Sr metabolism in the pregnant woman was based on a biokinetic model for the adult female modified to account for changes in mineral metabolism during pregnancy. The model for non-pregnant females of all ages was developed earlier with the use of extensive data on 90 Sr-body measurements in the Techa Riverside residents. To determine changes in model parameter values to take account of changing mineral metabolism during pregnancy, data from longitudinal studies of calcium homeostasis during human pregnancy were analysed and applied. Exchanges between maternal and fetal circulations and retention in fetal skeleton and soft tissues were modelled as adaptations of previously published models, taking account of data on Sr and calcium (Ca) metabolism obtained in Russia (Southern Urals and Moscow) relating to dietary calcium intakes, calcium contents in maternal and fetal skeletons and strontium transfer to the fetus. The model was validated using independent data on 90 Sr in the fetal skeleton from global fallout as well as unique data on 90 Sr-body burden in mothers and their still-born children for Techa River residents. While the Sr-PWF model has been developed specifically for ingestion of Sr isotopes by Techa River residents, it is also more widely applicable to maternal ingestion of Sr radioisotopes at different times before and during pregnancy and different ages of pregnant women in a general population. (paper)

  1. 99mTc-UBI Biokinetics: A Specific Peptide for Infection Detection

    Science.gov (United States)

    Rodríguez-Cortés, J.; Meléndez-Alafort, L.; Herrera-Rodríguez, R.; Ferro-Flores, G.; Mitsoura, E.; Martínez-Duncker, C.

    2003-09-01

    Recently, antimicrobial peptides have been proposed as new agents to distinguish between bacterial infections and sterile inflammatory processes. Based on these considerations, Ubiquicidin peptide 29-41 (UBI) has been labeled with 99mTc using a new direct method showing a radiochemical purity > 97 %, high stability in human serum, and low protein binding. In addition 99mTc-UBI showed a specific in vitro and in vivo binding to bacteria. However its biokinetic parameters have not been evaluated since it is one of the new generation radiopharmaceuticals based on peptide structures. Therefore the aim of this project was to establish the biokinetic model for 99mTc-UBI. An activity from 74 to 148 MBq was injected to patients with bone infection and 5 whole body scans were taken at 1, 30, 120, 240 min and 24 h after radiopharmaceutical administration, with a dual head scanner. Urine was collected for 24 h. An antropomorphic phantom was previously used to calculate the effect of attenuation and scattered radiation on the gamma camera acquisition images. ROIs of the selected organs in patients (kidney, liver, heart, bone, soft tissue and lesion) were drawn, and attenuation and scatter corrected. The % urine elimination at 24 h and time integrated ROIs (cpm/pixel/ROIs) were used to obtain the residence time (τ) in each tissue and to establish the biokinetic model. Pharmacokinetic data show that blood clearance is biexponential with a mean residence time in the central compartment of 0.52 h. The images showed non-accumulation in metabolic organs. More than 75 % of the injected activity was eliminated by renal clearance 4 h after 99mTc-UBI administration. The mean radiation dose calculated according to the MIRD formalism was 0.130 mGy/MBq for kidney and the effective dose was 4.29 × 10-3 mSv/MBq.

  2. Recent developments in biokinetic models and the calculation of internal dose coefficients

    International Nuclear Information System (INIS)

    Fell, T.P.; Phipps, A.W.; Kendall, G.M.; Stradling, G.N.

    1997-01-01

    In most cases the measurement of radioactivity in an environmental or biological sample will be followed by some estimation of dose and possibly risk, either to a population or an individual. This will normally involve the use of a dose coefficient (dose per unit intake value) taken from a compendium. In recent years the calculation of dose coefficients has seen many developments in both biokinetic modelling and computational capabilities. ICRP has recommended new models for the respiratory tract and for the systemic behavior of many of the more important elements. As well as this, a general age-dependent calculation method has been developed which involves an effectively continuous variation of both biokinetic and dosimetric parameters, facilitating more realistic estimation of doses to young people. These new developments were used in work for recent ICRP, IAEA and CEC compendia of dose coefficients for both members of the public (including children) and workers. This paper presents a general overview of the method of calculation of internal doses with particular reference to the actinides. Some of the implications for dose coefficients of the new models are discussed. For example it is shown that compared with data in ICRP Publications 30 and 54: the new respiratory tract model generally predicts lower deposition in systemic tissues per unit intake; the new biokinetic models for actinides allow for burial of material deposited on bone surfaces; age-dependent models generally feature faster turnover of material in young people. All of these factors can lead to substantially different estimates of dose and examples of the new dose coefficients are given to illustrate these differences. During the development of the new models for actinides, human bioassay data were used to validate the model. Thus, one would expect the new models to give reasonable predictions of bioassay quantities. Some examples of the bioassay applications, e.g., excretion data for the

  3. Instrumentation for Dosimetry. Chapter 21

    Energy Technology Data Exchange (ETDEWEB)

    Hourdakis, J. C. [Greek Atomic Energy Commission, Athens (Greece); Nowotny, R. [Medical University of Vienna, Vienna (Austria)

    2014-09-15

    Measurements of absorbed dose (or air kerma) are required in varying situations in diagnostic radiology. The radiation fields vary from plain, slit and even point projection geometry, and may be stationary or moving, including rotational. Owing to the use of low photon energies for these fields, it is important that dosimeters have a satisfactory energy response. In general, the requirements for dosimeter accuracy are less stringent than those in radiation therapy; however, the dose and dose rate measurements cover a large range. Patient dosimetry (see Chapter 22) is a primary responsibility of the medical physicist specializing in diagnostic radiology and is required by legislation in many countries. Dose data are also required in the optimization of examinations for image quality and dose. Radiation measurement is also critical for occupational and public exposure control (see Chapter 24). Dose measurements are essential in acceptance testing and quality control (see Chapter 19). Several types of dosimeter can be used, provided that they have a suitable energy response, but typically, ionization chambers of a few cubic centimetres in volume, or solid state detectors specifically designed for such measurements, are used. If dosimeters are used to make measurements during an examination, they must not interfere with the examination. These devices are also used for determination of the half value layer (HVL). Special types of ionization chamber are employed for computed tomography (CT), mammography and interventional radiology dosimetry.

  4. Age-specific models for evaluating dose and risk from internal exposures to radionuclides: Report of current work of the Metabolism and Dosimetry Research Group, July 1, 1985-June 30, 1987

    International Nuclear Information System (INIS)

    Leggett, R.W.; Warren, B.P.

    1987-09-01

    A projection of the health risk to a population internally exposed to a radionuclide requires explicit or implicit use of demographic, biokinetic, dosimetric, and dose-response models. Exposure guidelines have been based on models for a reference adult with a fixed life span. In this report, we describe recent efforts to develop a comprehensive methodology for estimation of radiogenic risk to individuals and to heterogeneous populations. Emphasis is on age-dependent biokinetics and dosimetry for internal emitters, but consideration also is given to conversion of age-specific doses to estimates of risk using realistic, site-specific demographic models and best available age-specific dose-response functions. We discuss how the methods described here may also improve estimates for the reference adult usually considered in radiation protection. 159 refs

  5. Age-specific models for evaluating dose and risk from internal exposures to radionuclides: Report of current work of the Metabolism and Dosimetry Research Group, July 1, 1985-June 30, 1987

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W.; Warren, B.P. (eds.)

    1987-09-01

    A projection of the health risk to a population internally exposed to a radionuclide requires explicit or implicit use of demographic, biokinetic, dosimetric, and dose-response models. Exposure guidelines have been based on models for a reference adult with a fixed life span. In this report, we describe recent efforts to develop a comprehensive methodology for estimation of radiogenic risk to individuals and to heterogeneous populations. Emphasis is on age-dependent biokinetics and dosimetry for internal emitters, but consideration also is given to conversion of age-specific doses to estimates of risk using realistic, site-specific demographic models and best available age-specific dose-response functions. We discuss how the methods described here may also improve estimates for the reference adult usually considered in radiation protection. 159 refs.

  6. Quantitative biokinetic analysis of radioactively labelled, inhaled Titanium dioxide Nanoparticles in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Kreyling, Wolfgang G.; Wenk, Alexander; Semmler-Behnke, Manuela [Helmholtz Zentrum Muenchen, Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH (Germany). Inst. fuer Lungenbiologie und Erkrankungen, Netzwerk Nanopartikel und Gesundheit

    2010-09-15

    The aim of this project was the determination of the biokinetics of TiO{sub 2} nanoparticles (NP) in the whole body of healthy adult rats after NP administration to the respiratory tract - either via inhalation or instillation. We developed an own methodology to freshly synthesize and aerosolize TiO{sub 2}-NP in our lab for the use of inhalation studies. These NP underwent a detailed physical and chemical characterization providing pure polycrystalline anatase TiO{sub 2}-NP of about 20 nm (geometric standard deviation 1.6) and a specific surface area of 270 m{sup 2}/g. In addition, we developed techniques for sufficiently stable radioactive {sup 48}V labelling of the TiO{sub 2} NP. The kinetics of solubility of {sup 48}V was thoroughly determined. The methodology of quantitative biokinetics allows for a quantitative balance of the retained and excreted NP in control of the administered NP dose and provides a much more precise determination of NP fractions and concentrations of NP in organs and tissues of interest as compared to spotting biokinetics studies. Small fractions of TiO{sub 2}-NP translocate across the air-blood-barrier and accumulate in secondary target organs, soft tissue and skeleton. The amount of translocated TiO{sub 2}-NP is approximately 2% of TiO{sub 2}-NP deposited in the lungs. A prominent fraction of these translocated TiO{sub 2}-NP was found in the remainder. Smaller amounts of TiO{sub 2}-NP accumulate in secondary organs following particular kinetics. TiO{sub 2}-NP translocation was grossly accomplished within the first 2-4 hours after inhalation followed by retention in all organs and tissues studied without any detectable clearance of these biopersistent TiO{sub 2}-NP within 28 days. Therefore, our data suggest crossing of the air-blood-barrier of the lungs and subsequent accumulation in secondary organs and tissues depends on the NP material and its physico-chemical properties. Furthermore, we extrapolate that during repeated or chronic

  7. Quantitative biokinetic analysis of radioactively labelled, inhaled Titanium dioxide Nanoparticles in a rat model

    International Nuclear Information System (INIS)

    Kreyling, Wolfgang G.; Wenk, Alexander; Semmler-Behnke, Manuela

    2010-01-01

    The aim of this project was the determination of the biokinetics of TiO 2 nanoparticles (NP) in the whole body of healthy adult rats after NP administration to the respiratory tract - either via inhalation or instillation. We developed an own methodology to freshly synthesize and aerosolize TiO 2 -NP in our lab for the use of inhalation studies. These NP underwent a detailed physical and chemical characterization providing pure polycrystalline anatase TiO 2 -NP of about 20 nm (geometric standard deviation 1.6) and a specific surface area of 270 m 2 /g. In addition, we developed techniques for sufficiently stable radioactive 48 V labelling of the TiO 2 NP. The kinetics of solubility of 48 V was thoroughly determined. The methodology of quantitative biokinetics allows for a quantitative balance of the retained and excreted NP in control of the administered NP dose and provides a much more precise determination of NP fractions and concentrations of NP in organs and tissues of interest as compared to spotting biokinetics studies. Small fractions of TiO 2 -NP translocate across the air-blood-barrier and accumulate in secondary target organs, soft tissue and skeleton. The amount of translocated TiO 2 -NP is approximately 2% of TiO 2 -NP deposited in the lungs. A prominent fraction of these translocated TiO 2 -NP was found in the remainder. Smaller amounts of TiO 2 -NP accumulate in secondary organs following particular kinetics. TiO 2 -NP translocation was grossly accomplished within the first 2-4 hours after inhalation followed by retention in all organs and tissues studied without any detectable clearance of these biopersistent TiO 2 -NP within 28 days. Therefore, our data suggest crossing of the air-blood-barrier of the lungs and subsequent accumulation in secondary organs and tissues depends on the NP material and its physico-chemical properties. Furthermore, we extrapolate that during repeated or chronic exposure to insoluble NP the translocated fraction of NP will

  8. Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Meck, Robert A. [U.S. Nuclear Regulatory Commission

    2008-10-01

    This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intake or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many infrequently

  9. Comparison of predicted with observed biokinetics of inhaled plutonium nitrate and gadolinium oxide in humans

    International Nuclear Information System (INIS)

    Hodgson, A.; Shutt, A.L.; Etherington, G.; Hodgson, S.A.; Rance, E.; Stradling, G.N.; Youngman, M.J.; Ziesenis, A.; Kreyling, W.G.

    2003-01-01

    The absorption kinetics to blood of plutonium and gadolinium after inhalation as nitrate and oxide in humans and animals has been studied. For each material, values describing the time dependence of absorption were derived from the studies in animals and used with the ICRP human respiratory tract model to predict lung retention and cumulative amounts to blood for the volunteers inhaling the same materials. Comparison with the observed behaviour in the volunteers suggests that absorption of plutonium and gadolinium is reasonably species independent, and that data obtained from animal studies can be used to assess their biokinetic behaviour in humans. (author)

  10. Biokinetics and bacterial communities of propionate oxidizing bacteria in phased anaerobic sludge digestion systems.

    Science.gov (United States)

    Zamanzadeh, Mirzaman; Parker, Wayne J; Verastegui, Yris; Neufeld, Josh D

    2013-03-15

    Phased anaerobic digestion is a promising technology and may be a potential source of bio-energy production. Anaerobic digesters are widely used for sewage sludge stabilization and thus a better understanding of the microbial process and kinetics may allow increased volatile solids reduction and methane production through robust process operation. In this study, we analyzed the impact of phase separation and operational conditions on the bio-kinetic characteristics and communities of bacteria associated with four phased anaerobic digestion systems. In addition to significant differences between bacterial communities associated with different digester operating temperatures, our results also revealed that bacterial communities in the phased anaerobic digestion systems differed between the 1st and 2nd phase digesters and we identified strong community composition correlations with several measured physicochemical parameters. The maximum specific growth rates of propionate oxidizing bacteria (POB) in the mesophilic and thermophilic 1st phases were 11 and 23.7 mgCOD mgCOD(-1) d(-1), respectively, while those of the mesophilic and thermophilic 2nd-phase digesters were 6.7 and 18.6 mgCOD mgCOD(-1) d(-1), respectively. Hence, the biokinetic characteristics of the POB population were dependent on the digester loading. In addition, we observed that the temperature dependency factor (θ) values were higher for the less heavily loaded digesters as compared to the values obtained for the 1st-phase digesters. Our results suggested the appropriate application of two sets of POB bio-kinetic that reflect the differing growth responses as a function of propionate concentration (and/or organic loading rates). Also, modeling acetogenesis in phased anaerobic sludge digestion systems will be improved considering a population shift in separate phases. On the basis of the bio-kinetic values estimated in various digesters, high levels of propionate in the thermophilic digesters may be

  11. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2009-08-28

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document.

  12. Current trends on internal dosimetry for patient protection in nuclear medicine

    International Nuclear Information System (INIS)

    Rojo, A.M.; Gisone, P.A.; Kunst, J.J.

    2001-01-01

    The associated risk-benefit analyses in nuclear medicine implicitly performed by the clinician have been straightforward. Relatively low administered activity activities yield important diagnostic information, the benefit of which far outweigh any potential risk associated with the attendant normal tissue radiation doses. Such small risk to benefit ratios have been very forgiving of possible inaccuracies in dose estimates. With the ongoing development of new radiopharmaceutical and the increasing therapeutic application of internal radionuclides, radiation dosimetry in nuclear medicine continues to evolve from population- and organ-average to patient-specific dose estimation. Patient-specific dosimetry refers to the estimation of radiation dose to tissues of a specific-patients based on their individual body and measured biokinetics rather than an average anthropomorphic model and hypothetic kinetic. The importance of dosimetry specific-patient considers to avoid the risk of an unsuitable treatment and/or with probability of damage to the patient. This is illustrated by the dosimetric approaches to radioiodine treatment of hyperthyroidism. The most common prescription algorithm to fix the activity administered to a hyperthyroid patient does not consider individual parameters that are highly variable (thyroid uptake, biological half-life, thyroid mass). Its arbitrary approach doesn't permit individually optimized therapy and it may be inappropriate and even hazardous. (author)

  13. Next decade in external dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1988-01-01

    In recent years, a number of external dosimetry problems have been solved. However, changes in standards and legal concepts relating to the application of dosimetry results will require further enhancements in measurement techniques and philosophy in the next 10 y. The introduction of effective dose equivalent and the legal use of probability of causation will require that much greater attention be given to determination of weighted organ dose from external exposure. An imminent change--an increase in the fast neutron quality factor--will require a new round of technology development in a field that has just received a decade of close scrutiny. For the future, we must take advantage of developments in microelectronics. The use of random access memory (RAM) and metal-on-silicon (MOS) devices as detector elements, particularly for neutron dosimetry, has exciting possibilities that are just beginning to be explored. Advances in microcircuitry are leading, and will continue to lead, in the development of a new generation of small, rugged and smart radiation survey instruments that will make the most of detector data. It has become possible with very compact instruments to obtain energy spectra, linear-energy-transfer (LET) spectra, and quality factors in addition to the usual integrated dosimetric quantities: exposure, absorbed dose, and dose equivalent. These instruments will be reliable and easy to use. The user will be able to select the level of sophistication that is required for any specific application. Moreover, since the processing algorithms can be changed, changes in conversion factors can be accommodated with relative ease. During the next decade, the use of computers will continue to grow in value to the health physicist

  14. A-bomb survivor dosimetry update

    International Nuclear Information System (INIS)

    Loewe, W.E.

    1982-06-01

    A-bomb survivor data have been generally accepted as applicable. Also, the initial radiations have tended to be accepted as the dominant radiation source for all survivors. There was general acceptance of the essential reliability of both the biological effects data and the causative radiation dose values. There are considerations casting doubt on these acceptances, but very little quantification of th implied uncertainties has been attempted. The exception was A-bomb survivor dosimetry, where free-field kerma values for initial radiations were thought to be accurate to about 30%, and doses to individual survivors were treated as effectively error-free. In 1980, a major challenge to the accepted A-bomb survivor dosimetry was announced, and was quickly followed by a succession of explanations and displays showing the soundness of that challenge. In fact, a complete replacement set of free-field kerma values was provided which was suitable for use in constructing an entire new dosimetry for Hiroshima and Nagasaki. The new values showed many changes greater than the accepted 30% uncertainty. An approximate new dosimetry was indeed constructed, and used to convert existing leukemia cause-and-effect data from the old to the new dose values, by way of assessing the impact

  15. 131I-SPGP internal dosimetry: animal model and human extrapolation

    International Nuclear Information System (INIS)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soprani, Juliana; Santos, Raquel Gouvea dos; Figueiredo, Suely Gomes de

    2009-01-01

    Scorpaena plumieri is commonly called moreia-ati or manganga and is the most venomous and one of the most abundant fish species of the Brazilian coast. Soprani 2006, demonstrated that SPGP - an isolated protein from S. plumieri fish- possess high antitumoral activity against malignant tumours and can be a source of template molecules for the development (design) of antitumoral drugs. In the present work, Soprani's 125 ISPGP biokinetic data were treated by MIRD formalism to perform Internal Dosimetry studies. Absorbed doses due to the 131 I-SPGP uptake were determinate in several organs of mice, as well as in the implanted tumor. Doses obtained for animal model were extrapolated to humans assuming a similar ratio for various mouse and human tissues. For the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from 131 I were considered. (author)

  16. {sup 131}I-CRTX internal dosimetry: animal model and human extrapolation

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: hma@cdtn.br

    2009-07-01

    Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. {sup 125}I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, {sup 125}I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for {sup 131}I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 131}I in the tissue were considered in dose calculations. (author)

  17. {sup 131}I-SPGP internal dosimetry: animal model and human extrapolation

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soprani, Juliana; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: hma@cdtn.br; Figueiredo, Suely Gomes de [Universidade Federal do Espirito Santo, (UFES), Vitoria, ES (Brazil). Dept. de Ciencias Fisiologicas. Lab. de Quimica de Proteinas

    2009-07-01

    Scorpaena plumieri is commonly called moreia-ati or manganga and is the most venomous and one of the most abundant fish species of the Brazilian coast. Soprani 2006, demonstrated that SPGP - an isolated protein from S. plumieri fish- possess high antitumoral activity against malignant tumours and can be a source of template molecules for the development (design) of antitumoral drugs. In the present work, Soprani's {sup 125}ISPGP biokinetic data were treated by MIRD formalism to perform Internal Dosimetry studies. Absorbed doses due to the {sup 131}I-SPGP uptake were determinate in several organs of mice, as well as in the implanted tumor. Doses obtained for animal model were extrapolated to humans assuming a similar ratio for various mouse and human tissues. For the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 131}I were considered. (author)

  18. 131I-CRTX internal dosimetry: animal model and human extrapolation

    International Nuclear Information System (INIS)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos

    2009-01-01

    Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. 125 I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, 125 I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for 131 I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from 131 I in the tissue were considered in dose calculations. (author)

  19. Neutron dosimetry in biology

    International Nuclear Information System (INIS)

    Sigurbjoernsson, B.; Smith, H.H.; Gustafsson, A.

    1965-01-01

    To study adequately the biological effects of different energy neutrons it is necessary to have high-intensity sources which are not contaminated by other radiations, the most serious of which are gamma rays. An effective dosimetry must provide an accurate measure of the absorbed dose, in biological materials, of each type of radiation at any reactor facility involved in radiobiological research. A standardized biological dosimetry, in addition to physical and chemical methods, may be desirable. The ideal data needed to achieve a fully documented dosimetry has been compiled by H. Glubrecht: (1) Energy spectrum and intensity of neutrons; (2) Angular distribution of neutrons on the whole surface of the irradiated object; (3) Additional undesired radiation accompanying the neutrons; (4) Physical state and chemical composition of the irradiated object. It is not sufficient to note only an integral dose value (e.g. in 'rad') as the biological effect depends on the above data

  20. Application of artificial neural network for development of an algorithm for TLD badge system in the mixed field dosimetry of X and gamma radiation in terms of Hp(10)

    International Nuclear Information System (INIS)

    Srivastava, K.; Bakshi, A.K.; Geetha, V.; Kher, R.K.; Dhar, V.K.

    2005-01-01

    ICRU has introduced new operational quantities for individual monitoring. Therefore it is required to develop an algorithm that gives direct response of the TLD badge in terms of the operational quantities. For this purpose and also to improve the precision in the mixed fields dosimetry, two methods were studied i)- analytical method by developing an algorithm based on of higher order polynomial fit of the data points for known delivered doses and ii) use of Artificial Neural Network (ANN). Study on the response of the TLD badge system based on CaSO 4 : Dy Teflon TLD discs in the mixed fields of X and gamma radiation in terms of operational quantity Hp(10) was carried out using the prevalent algorithm, algorithm developed using higher order polynomial and neural network predicted algorithm for different proportion of dose delivered by X and gamma radiations. It was found that the uncertainties in the dose response for few fields are beyond the acceptable limit for prevalent algorithm and within the acceptable limit for other two algorithms. Algorithm based on ANN gives higher precision in the mixed field of two radiations compared to other two algorithms. (author)

  1. TH-AB-BRA-06: MOSFET-Based Dosimetry in An MR Image-Guided Radiation Therapy System: Comparison with and Without a Static 0.3T Magnetic Field

    Energy Technology Data Exchange (ETDEWEB)

    Cammin, J; Curcuru, A; Li, H; Mutic, S; Green, O [Washington University School of Medicine, St. Louis, MO (United States)

    2016-06-15

    Purpose: To compare depth-dose and surface-dose measurements without and with the magnetic field in a 0.3T MR image-guided Co-60 treatment unit using MOSFET dosimeters. Methods: MOSFET dosimeters (Best Medical Canada, model TN-502RDH-10) were placed in a solid water phantom at 5cm depth with 8cm backscatter (with the MOSFET wires in different orientations to the couch long axis) and also on the surface of an 8cm solid water phantom. The phantoms were placed in an MR image-guided Co-60 treatment machine at an SAD of 105cm to the MOSFETs. Dose measurements were performed between 50 and 200cGy at 5cm depth in a 10.5cm × 10.5cm radiation field without the magnetic field (during a machine maintenance period) and with the nominal magnetic field of 0.3T. The dose linearity was measured at 5cm depth with an orthogonal field and the angular dose dependence was measured on the surface with an orthogonal field and oblique fields at +60 degrees and −60 degrees. Results: The measured MOSFET readings at 5cm depth were linear with dose with slopes of (2.97 +/− 0.01) mV/cGy and (3.01 +/− 0.02) mV/cGy without and with the magnetic field, respectively. No statistically significant difference was found. The surface dose measurements, however, were lower by 6.4% for the AP field (2.3 σ) with magnetic field, 4.9% for the −60 degree field (1.4 σ), and 0.4% different for the +60 degree field (0.2 σ). Conclusion: There is no statistically significant difference in the dose at depth without and with the magnetic field and different orientations of the MOSFET wires. There is a statistically significant difference for the surface dose due to the influence of the magnetic field on secondary electrons from head-scatter and the build-up region in certain field orientations. Clinical surface-dose dosimetry in a magnetic field should apply asymmetric angle-dependent corrections.

  2. SU-F-SPS-01: Accuracy of the Small Field Dosimetry Using Acuros XB and AAA Dose Calculation Algorithms of Eclipse Treatment Planning System Within and Beyond Heterogeneous Media for Trubeam 2.0 Unit

    International Nuclear Information System (INIS)

    Codel, G; Serin, E; Pacaci, P; Sanli, E; Cebe, M; Mabhouti, H; Doyuran, M; Kucukmorkoc, E; Kucuk, N; Altinok, A; Canoglu, D; Acar, H; Caglar Ozkok, H

    2016-01-01

    Purpose: In this study, the comparison of dosimetric accuracy of Acuros XB and AAA algorithms were investigated for small radiation fields incident on homogeneous and heterogeneous geometries Methods: Small open fields of Truebeam 2.0 unit (1×1, 2×2, 3×3, 4×4 fields) were used for this study. The fields were incident on homogeneous phantom and in house phantom containing lung, air, and bone inhomogeneities. Using the same film batch, the net OD to dose calibration curve was obtaine dusing Trubeam 2.0 for 6 MV, 6 FFF, 10 MV, 10 FFF, 15 MV energies by delivering 0- 800 cGy. Films were scanned 48 hours after irradiation using an Epson 1000XL flatbed scanner. The dosimetric accuracy of Acuros XB and AAA algorithms in the presence of the inhomogeneities was compared against EBT3 film dosimetry Results: Open field tests in a homogeneous phantom showed good agreement betweent wo algorithms and measurement. For Acuros XB, minimum gamma analysis passin grates between measured and calculated dose distributions were 99.3% and 98.1% for homogeneousand inhomogeneous fields in thecase of lung and bone respectively. For AAA, minimum gamma analysis passingrates were 99.1% and 96.5% for homogeneous and inhomogeneous fields respectively for all used energies and field sizes.In the case of the air heterogeneity, the differences were larger for both calculations algorithms. Over all, when compared to measurement, theAcuros XB had beter agreement than AAA. Conclusion: The Acuros XB calculation algorithm in the TPS is an improvemen tover theexisting AAA algorithm. Dose discrepancies were observed for in the presence of air inhomogeneities.

  3. SU-F-SPS-01: Accuracy of the Small Field Dosimetry Using Acuros XB and AAA Dose Calculation Algorithms of Eclipse Treatment Planning System Within and Beyond Heterogeneous Media for Trubeam 2.0 Unit

    Energy Technology Data Exchange (ETDEWEB)

    Codel, G; Serin, E; Pacaci, P; Sanli, E; Cebe, M; Mabhouti, H; Doyuran, M; Kucukmorkoc, E; Kucuk, N; Altinok, A; Canoglu, D; Acar, H; Caglar Ozkok, H [Medipol University, Istanbul, Istanbul (Turkey)

    2016-06-15

    Purpose: In this study, the comparison of dosimetric accuracy of Acuros XB and AAA algorithms were investigated for small radiation fields incident on homogeneous and heterogeneous geometries Methods: Small open fields of Truebeam 2.0 unit (1×1, 2×2, 3×3, 4×4 fields) were used for this study. The fields were incident on homogeneous phantom and in house phantom containing lung, air, and bone inhomogeneities. Using the same film batch, the net OD to dose calibration curve was obtaine dusing Trubeam 2.0 for 6 MV, 6 FFF, 10 MV, 10 FFF, 15 MV energies by delivering 0- 800 cGy. Films were scanned 48 hours after irradiation using an Epson 1000XL flatbed scanner. The dosimetric accuracy of Acuros XB and AAA algorithms in the presence of the inhomogeneities was compared against EBT3 film dosimetry Results: Open field tests in a homogeneous phantom showed good agreement betweent wo algorithms and measurement. For Acuros XB, minimum gamma analysis passin grates between measured and calculated dose distributions were 99.3% and 98.1% for homogeneousand inhomogeneous fields in thecase of lung and bone respectively. For AAA, minimum gamma analysis passingrates were 99.1% and 96.5% for homogeneous and inhomogeneous fields respectively for all used energies and field sizes.In the case of the air heterogeneity, the differences were larger for both calculations algorithms. Over all, when compared to measurement, theAcuros XB had beter agreement than AAA. Conclusion: The Acuros XB calculation algorithm in the TPS is an improvemen tover theexisting AAA algorithm. Dose discrepancies were observed for in the presence of air inhomogeneities.

  4. Report of a consultants meeting on dosimetry in diagnostic radiology

    International Nuclear Information System (INIS)

    Pernicka, F.

    1999-01-01

    During its biennial meeting in 1996, the Standing Advisory Committee 'SSDL Scientific Committee', recommended extending the long experience of the Agency in the field of standardization and monitoring dosimetry calibrations at radiotherapy and radiation protection level for the Secondary Standard Dosimetry Laboratory (SSDL) Network, to the field of diagnostic x-ray dosimetry. It was emphasized that 'Measurements on diagnostic x-ray machines have become increasingly important and some SSDLs are involved in such measurements. The Agency's dosimetry laboratory should, therefore, have proper radiation sources available to provide traceable calibrations to the SSDLs'. The purpose of the consultants' meeting was to advise the Agency on dosimetry in diagnostic radiology. They were specifically requested to overview scientific achievements in the field and to give advice to the Agency on the need for further developments. The purpose of the consultants' meeting was to advise the Agency on dosimetry in diagnostic radiology. They were specifically requested to overview scientific achievements in the field and to give advice to the Agency on the need for further developments

  5. Reactor Dosimetry State of the Art 2008

    Science.gov (United States)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

    2009-08-01

    . Williams, A. P. Ribaric and T. Schnauber. Agile high-fidelity MCNP model development techniques for rapid mechanical design iteration / J. A. Kulesza.Extension of Raptor-M3G to r-8-z geometry for use in reactor dosimetry applications / M. A. Hunter, G. Longoni and S. L. Anderson. In vessel exposure distributions evaluated with MCNP5 for Atucha II / J. M. Longhino, H. Blaumann and G. Zamonsky. Atucha I nuclear power plant azimutal ex-vessel flux profile evaluation / J. M. Longhino ... [et al.]. UFTR thermal column characterization and redesign for maximized thermal flux / C. Polit and A. Haghighat. Activation counter using liquid light-guide for dosimetry of neutron burst / M. Hayashi ... [et al.]. Control rod reactivity curves for the annular core research reactor / K. R. DePriest ... [et al.]. Specification of irradiation conditions in VVER-440 surveillance positions / V. Kochkin ... [et al.]. Simulations of Mg-Ar ionisation and TE-TE ionisation chambers with MCNPX in a straightforward gamma and beta irradiation field / S. Nievaart ... [et al.]. The change of austenitic stainless steel elements content in the inner parts of VVER-440 reactor during operation / V. Smutný, J. Hep and P. Novosad. Fast neutron environmental spectrometry using disk activation / G. Lövestam ... [et al.]. Optimization of the neutron activation detector location scheme for VVER-lOOO ex-vessel dosimetry / V. N. Bukanov ... [et al.]. Irradiation conditions for surveillance specimens located into plane containers installed in the WWER-lOOO reactor of unit 2 of the South-Ukrainian NPP / O. V. Grytsenko. V. N. Bukanov and S. M. Pugach. Conformity between LRO mock-ups and VVERS NPP RPV neutron flux attenuation / S. Belousov. Kr. Ilieva and D. Kirilova. FLUOLE: a new relevant experiment for PWR pressure vessel surveillance / D. Beretz ... [et al.]. Transport of neutrons and photons through the iron and water layers / M. J. Kost'ál ... [et al.]. Condition evaluation of spent nuclear fuel assemblies

  6. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact their dispatchers to explain their activities for the future, after LEP dismantling in order to be maintained on the regular distribution list at Individual DosimetryWe inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period MAY/JUNE will be available from their usual dispatchers on Tuesday 2 May.Please have your films changed before the 12 May.The colour of the dosimeter valid in is MAY/JUNE is YELLOW.Individual Dosimetry Service will be closed on Friday 28 April.

  7. Nuclear medicine radiation dosimetry

    CERN Document Server

    McParland, Brian J

    2010-01-01

    Complexities of the requirements for accurate radiation dosimetry evaluation in both diagnostic and therapeutic nuclear medicine (including PET) have grown over the past decade. This is due primarily to four factors: growing consideration of accurate patient-specific treatment planning for radionuclide therapy as a means of improving the therapeutic benefit, development of more realistic anthropomorphic phantoms and their use in estimating radiation transport and dosimetry in patients, design and use of advanced Monte Carlo algorithms in calculating the above-mentioned radiation transport and

  8. Need of Reactor Dosimetry Preservation

    International Nuclear Information System (INIS)

    Ilieva, Krassimira

    2011-01-01

    The nuclear safety requirements and philosophy have changed by the development of new nuclear systems and this imposes special research and development activity. Reactor dosimetry which is applied for determination of neutron field parameters and neutron flux responses in different regions of the reactor system plays an important role in determining of radiation exposure on reactor system elements as reactor vessel, internals, shielding; dose determination for material damage study; for conditioning of irradiation; dose determination for medicine and industry application; induced activity determination for decommissioning purposes. The management of nuclear knowledge has emerged as a growing challenge in recent years. The need to preserve and transfer nuclear knowledge is compounded by recent trends such as ageing of the nuclear workforce, declining student numbers in nuclear related fields, and the threat of losing accumulated nuclear knowledge. (author)

  9. Benchmark referencing of neutron dosimetry measurements

    International Nuclear Information System (INIS)

    Eisenhauer, C.M.; Grundl, J.A.; Gilliam, D.M.; McGarry, E.D.; Spiegel, V.

    1980-01-01

    The concept of benchmark referencing involves interpretation of dosimetry measurements in applied neutron fields in terms of similar measurements in benchmark fields whose neutron spectra and intensity are well known. The main advantage of benchmark referencing is that it minimizes or eliminates many types of experimental uncertainties such as those associated with absolute detection efficiencies and cross sections. In this paper we consider the cavity external to the pressure vessel of a power reactor as an example of an applied field. The pressure vessel cavity is an accessible location for exploratory dosimetry measurements aimed at understanding embrittlement of pressure vessel steel. Comparisons with calculated predictions of neutron fluence and spectra in the cavity provide a valuable check of the computational methods used to estimate pressure vessel safety margins for pressure vessel lifetimes

  10. A physiological skeletal model for radionuclide and stable element biokinetics in children and adults

    International Nuclear Information System (INIS)

    Richardson, R.B.

    2010-01-01

    A physiological skeletal model (PSM) is described that represents the skeletal uptake, retention and clearance of both bone-surface-seeking and bone-volume-seeking radionuclides and stable elements. A key objective of the PSM is to model the higher skeletal growth and bone turnover in infants and children (compared to adults) in order to to account for their greater uptake and cancer risk from bone-seeking contaminants such as lead and plutonium. The PSM is a compartmental model that allows for the incorporation of organic and inorganic material in the bone volume via quiescent bone surfaces, forming bone surfaces and the lacuno-canaliculi system. The model uniquely incorporates a tertiary phase of mineralization via bone fluids. The PSM's structural concepts and biokinetic parameters - such as realistic mass transfers, organ and tissue masses, and bone remodelling half times - are selected mainly on the basis of physiological and anatomical criteria. For brevity, model parameter values or evaluated for adults only. The PSM is an improvement on existing skeletal models that are based more on compartment structures and pathways that rendered good fits to biokinetic data rather than on being anatomically and physiologically accurate. (author)

  11. Biokinetic study of plutonium and americium associated to the particulates of soil

    International Nuclear Information System (INIS)

    Espinosa, A.; Aragon, A.; Martinez, J.; Iranzo, C.E.

    1996-01-01

    The object of this study is to determine the biokinetic parameters of different Plutonium isotopes and Americium inhaled in the state in which they are found in the environment as a result of their deposition in the soil, from an aviation accident that generated different plutonium oxides. to achieve this objective, two lines of work planned. One was the determination of the mineralogical composition and associations that plutonium and americium present in that soil 22 years after the nuclear accident. Other studies were directed to determine the biokinetic of the plutonium isotopes and americium (contained in the dust) deposited tracheally and inhaled by laboratory animals (rats) and in vitro experiments by pulmonary leaching simulation. The in vivo tests have been developed in NRPB (U.K.) and the in vitro experiment, geochemical associations studies, assessment of internal doses to humans resulting from intake of plutonium and americium bearing dusts present in the contaminated area and establishment of ALIs for inhalation, were carried out in CIEMAT (Spain). In this work only determinations and experiments carried out by CIEMAT are includes as a part of the EU Project ''INHALATION AND INGESTION OF RADIONUCLIDES'' contract: FI3P-CT920064a. (Author) 10 refs

  12. Uranium: biokinetics and toxicity; Biocinetique et toxicite de l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A

    2000-07-01

    This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation.

  13. Fast neutron dosimetry: Progress summary

    International Nuclear Information System (INIS)

    DeLuca, P.M. Jr.

    1988-01-01

    The purpose was to investigate the radiological physics and biology of very low energy photons derived from a 1-GeV electron synchrotron storage ring. An extensive beam line and irradiation apparatus was designed, developed, and constructed. Dosimetry measurements required invention and testing of a miniature absolute calorimeter and a cell irradiation fixture suitable for scanning exposures under computer control. Measurements of the kerma factors of oxygen, aluminum and silicon for 14-20 MeV neutrons. Custom designed miniature proportional counters of cylindrical symmetry were employed in these determinations. The oxygen kerma factor was found significantly lower than values calculated from microscopic cross sections. We also tested Mg and Fe walled conventional spherical counters. The direct neutron-counting gas interaction is significant enough for these counters that a correction is needed. We also investigated the application of Nuclear Magnetic Resonance spectroscopy to radiation dosimetry. Our purpose was to take advantage of recent development of very high-field magnets, complex RF-pulse techniques for solvent suppression, and improved spectral analysis techniques

  14. SU-F-SPS-02: Accuracy of the Small Field Dosimetry Using the Monte Carlo and Sequential Dose Calculation Algorithms of Multiplan Treatment Planning System Within and Beyond Heterogeneous Media for Cyberknife M6 Unit

    Energy Technology Data Exchange (ETDEWEB)

    Serin, E.; Codel, G.; Mabhouti, H.; Cebe, M.; Sanli, E.; Pacaci, P.; Kucuk, N.; Kucukmorkoc, E.; Doyuran, M.; Canoglu, D.; Altinok, A.; Acar, H.; Caglar Ozkok, H. [Medipol University, Istanbul, Istanbul (Turkey)

    2016-06-15

    Purpose: In small field geometries, the electronic equilibrium can be lost, making it challenging for the dose-calculation algorithm to accurately predict the dose, especially in the presence of tissue heterogeneities. In this study, dosimetric accuracy of Monte Carlo (MC) advanced dose calculation and sequential algorithms of Multiplan treatment planning system were investigated for small radiation fields incident on homogeneous and heterogeneous geometries. Methods: Small open fields of fixed cones of Cyberknife M6 unit 100 to 500 mm2 were used for this study. The fields were incident on in house phantom containing lung, air, and bone inhomogeneities and also homogeneous phantom. Using the same film batch, the net OD to dose calibration curve was obtained using CK with the 60 mm fixed cone by delivering 0- 800 cGy. Films were scanned 48 hours after irradiation using an Epson 1000XL flatbed scanner. The dosimetric accuracy of MC and sequential algorithms in the presence of the inhomogeneities was compared against EBT3 film dosimetry Results: Open field tests in a homogeneous phantom showed good agreement between two algorithms and film measurement For MC algorithm, the minimum gamma analysis passing rates between measured and calculated dose distributions were 99.7% and 98.3% for homogeneous and inhomogeneous fields in the case of lung and bone respectively. For sequential algorithm, the minimum gamma analysis passing rates were 98.9% and 92.5% for for homogeneous and inhomogeneous fields respectively for used all cone sizes. In the case of the air heterogeneity, the differences were larger for both calculation algorithms. Overall, when compared to measurement, the MC had better agreement than sequential algorithm. Conclusion: The Monte Carlo calculation algorithm in the Multiplan treatment planning system is an improvement over the existing sequential algorithm. Dose discrepancies were observed for in the presence of air inhomogeneities.

  15. SU-F-SPS-02: Accuracy of the Small Field Dosimetry Using the Monte Carlo and Sequential Dose Calculation Algorithms of Multiplan Treatment Planning System Within and Beyond Heterogeneous Media for Cyberknife M6 Unit

    International Nuclear Information System (INIS)

    Serin, E.; Codel, G.; Mabhouti, H.; Cebe, M.; Sanli, E.; Pacaci, P.; Kucuk, N.; Kucukmorkoc, E.; Doyuran, M.; Canoglu, D.; Altinok, A.; Acar, H.; Caglar Ozkok, H.

    2016-01-01

    Purpose: In small field geometries, the electronic equilibrium can be lost, making it challenging for the dose-calculation algorithm to accurately predict the dose, especially in the presence of tissue heterogeneities. In this study, dosimetric accuracy of Monte Carlo (MC) advanced dose calculation and sequential algorithms of Multiplan treatment planning system were investigated for small radiation fields incident on homogeneous and heterogeneous geometries. Methods: Small open fields of fixed cones of Cyberknife M6 unit 100 to 500 mm2 were used for this study. The fields were incident on in house phantom containing lung, air, and bone inhomogeneities and also homogeneous phantom. Using the same film batch, the net OD to dose calibration curve was obtained using CK with the 60 mm fixed cone by delivering 0- 800 cGy. Films were scanned 48 hours after irradiation using an Epson 1000XL flatbed scanner. The dosimetric accuracy of MC and sequential algorithms in the presence of the inhomogeneities was compared against EBT3 film dosimetry Results: Open field tests in a homogeneous phantom showed good agreement between two algorithms and film measurement For MC algorithm, the minimum gamma analysis passing rates between measured and calculated dose distributions were 99.7% and 98.3% for homogeneous and inhomogeneous fields in the case of lung and bone respectively. For sequential algorithm, the minimum gamma analysis passing rates were 98.9% and 92.5% for for homogeneous and inhomogeneous fields respectively for used all cone sizes. In the case of the air heterogeneity, the differences were larger for both calculation algorithms. Overall, when compared to measurement, the MC had better agreement than sequential algorithm. Conclusion: The Monte Carlo calculation algorithm in the Multiplan treatment planning system is an improvement over the existing sequential algorithm. Dose discrepancies were observed for in the presence of air inhomogeneities.

  16. Dosimetry program for characterization of the FMIT facility

    International Nuclear Information System (INIS)

    Gold, R.; McElroy, W.N.; Fuller, J.L.; Sheen, E.M.; Dierckx, R.

    1979-01-01

    The environmental characterization program for the Fusion Materials Irradiaton Test (FMIT) facility is presented. Requirements for the development and testing of Magnetic Fusion Energy (MFE) materials together with the complexity of the FMIT (d,Li) generated radiation field warrant a multifaceted dosimetric approach. Specific passive, active and calculational dosimetry efforts comprising this multifaceted approach are described. Special emphasis is given to those dosimetry capabilities uniquely required to characterize FMIT

  17. Techniques for high dose dosimetry in industry, agriculture and medicine. Proceedings of a symposium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In radiation processing, it is important that the irradiated products are reliable and safe. For processes that impact directly on public health, dosimetry provides a formal means of regulation. For other applications, measurements are indispensable for process control to improve quality and the measurements have to be standardized. Thus, dosimetry is an essential part of quality standards for radiation processes. In the developing world, establishment of such quality standards is only in the embryonic stage, and the IAEA should and does play a role in the development and implementation of these standards. The IAEA initiated a programme of high dose dosimetry in 1977 to accomplish dose standardization on an industrial scale, to promote dosimetry as a quality control measure in radiation processing, and to help develop new dosimetry techniques. Since dosimetry has such a key role in these processes, the IAEA organized this international symposium to provide a forum for presentation and discussion of up-to-date developments in this field. Since the International Symposium on High Dose Dosimetry for Radiation Processing held in 1990 the field of dosimetry has deepened and broadened. There is a definite shift towards quality assurance, which calls for dependable dosimetry systems with well established traceability to national or international standards. Also, many new applications of radiation have been developed and for these new and innovative dosimetry methods are needed. This symposium has provided a forum for the discussion of many of these developments and consideration of the outstanding issues in these vital areas Refs, figs, tabs

  18. Techniques for high dose dosimetry in industry, agriculture and medicine. Proceedings of a symposium

    International Nuclear Information System (INIS)

    1999-03-01

    In radiation processing, it is important that the irradiated products are reliable and safe. For processes that impact directly on public health, dosimetry provides a formal means of regulation. For other applications, measurements are indispensable for process control to improve quality and the measurements have to be standardized. Thus, dosimetry is an essential part of quality standards for radiation processes. In the developing world, establishment of such quality standards is only in the embryonic stage, and the IAEA should and does play a role in the development and implementation of these standards. The IAEA initiated a programme of high dose dosimetry in 1977 to accomplish dose standardization on an industrial scale, to promote dosimetry as a quality control measure in radiation processing, and to help develop new dosimetry techniques. Since dosimetry has such a key role in these processes, the IAEA organized this international symposium to provide a forum for presentation and discussion of up-to-date developments in this field. Since the International Symposium on High Dose Dosimetry for Radiation Processing held in 1990 the field of dosimetry has deepened and broadened. There is a definite shift towards quality assurance, which calls for dependable dosimetry systems with well established traceability to national or international standards. Also, many new applications of radiation have been developed and for these new and innovative dosimetry methods are needed. This symposium has provided a forum for the discussion of many of these developments and consideration of the outstanding issues in these vital areas

  19. Comparison between two clones of Daphnia magna: effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics.

    Science.gov (United States)

    Guan, Rui; Wang, Wen-Xiong

    2006-03-10

    We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments.

  20. Comparison between two clones of Daphnia magna: Effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics

    International Nuclear Information System (INIS)

    Guan Rui; Wang Wenxiong

    2006-01-01

    We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments

  1. The in vitro biokinetics of chlorpromazine and diazepam in aggregating rat brain cell cultures after repeated exposure

    NARCIS (Netherlands)

    Broeders, Jessica J W; Hermens, Joop L M; Blaauboer, Bas J; Zurich, Marie-Gabrielle

    2015-01-01

    Neurotoxic effects of compounds can be tested in vitro using cell systems. One example is aggregating rat brain cell cultures. For the extrapolation of in vitro data to the in vivo situation, it is important to take the biokinetics of the test compound into account. In addition, the exposure in vivo

  2. A novel bench-scale column assay to investigate site-specific nitrification biokinetics in biological rapid sand filters

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

    2013-01-01

    A bench-scale assay was developed to obtain site-specific nitrification biokinetic information from biological rapid sand filters employed in groundwater treatment. The experimental set-up uses granular material subsampled from a full-scale filter, packed in a column, and operated with controlled...

  3. Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

    2016-01-01

    The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous...

  4. Personnel photographic film dosimetry

    International Nuclear Information System (INIS)

    Keirim-Markus, I.B.

    1981-01-01

    Technology of personnel photographic film dosimetry (PPD) based on the photographic effect of ionizing radiation is described briefly. Kinds of roentgen films used in PPD method are enumerated, compositions of a developer and fixing agents for these films are given [ru

  5. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1998-01-01

    The two tasks of the Dosimetry and Calibration Section at CERN are the Individual Dosimetry Service which assures the personal monitoring of about 5000 persons potentially exposed to ionizing radiation at CERN, and the Calibration Laboratory which verifies all the instruments and monitors. This equipment is used by the sections of the RP Group for assuring radiation protection around CERN's accelerators, and by the Environmental Section of TISTE. In addition, nearly 250 electronic and 300 quartz fibre dosimeters, employed in operational dosimetry, are calibrated at least once a year. The Individual Dosimetry Service uses an extended database (INDOS) which contains information about all the individual doses ever received at CERN. For most of 1997 it was operated without the support of a database administrator as the technician who had assured this work retired. The Software Support Section of TIS-TE took over the technical responsibility of the database, but in view of the many other tasks of this Section and the lack of personnel, only a few interventions for solving immediate problems were possible

  6. Dosimetry of pion beams

    International Nuclear Information System (INIS)

    Dicello, J.F.

    1975-01-01

    Negative pion beams are probably the most esoteric and most complicated type of radiation which has been suggested for use in clinical radiotherapy. Because of the limited availability of pion beams in the past, even to nuclear physicists, there exist relatively fewer basic data for this modality. Pion dosimetry is discussed

  7. High frequency electromagnetic dosimetry

    CERN Document Server

    Sánchez-Hernández, David A

    2009-01-01

    Along with the growth of RF and microwave technology applications, there is a mounting concern about the possible adverse effects over human health from electromagnetic radiation. Addressing this issue and putting it into perspective, this groundbreaking resource provides critical details on the latest advances in high frequency electromagnetic dosimetry.

  8. Group: radiation dosimetry

    International Nuclear Information System (INIS)

    Caldas, L.V.E.

    1990-01-01

    The main activities of the radiation dosimetry group is described, including the calibration of instruments, sources and radioactive solutions and the determination of neutron flux; development, production and market dosimetric materials; development radiation sensor make the control of radiation dose received by IPEN workers; development new techniques for monitoring, etc. (C.G.C.)

  9. Glucinium dosimetry in beryl

    International Nuclear Information System (INIS)

    Kremer, M.

    1949-05-01

    The application of the method developed by Kolthoff and Sandell (1928) for the dosimetry of glucinium (beryllium) in beryl gives non-reproducible results with up to 20% discrepancies. This method recommends to separate beryllium and aluminium using 8 hydroxyquinoline and then to directly precipitate glucinium in the filtrate using ammonia. One possible reason of the problems generated by this method should be the formation of a volatile complex between beryllium and the oxine. This work shows that when the oxine is eliminated before the precipitation with ammonia the dosimetry of beryllium becomes accurate. The destruction of the oxine requires the dry evaporation of the filtrate, which is a long process. Thus the search for a reagent allowing the quantitative precipitation of beryllium in its solutions and in presence of oxine has been made. It has been verified also that the quantitative precipitation of the double beryllium and ammonium phosphate is not disturbed by the oxine in acetic buffer. This method, which gives good results, has also the advantage to separate beryllium from the alkaline-earth compounds still present in the filtrate. The report details the operation mode of the method: beryllium dosimetry using ammonium phosphate, aluminium-beryllium separation, application to beryl dosimetry (ore processing, insolubilization of silica, precipitation with ammonia, precipitation with oxine, precipitation of PO 4 NH 4 Gl, preciseness). (J.S.)

  10. Instrumentation in thermoluminescence dosimetry

    International Nuclear Information System (INIS)

    Julius, H.W.

    1986-01-01

    In the performance of a thermoluminescence dosimetry (TLD) system the equipment plays an important role. Crucial parameters of instrumentation in TLD are discussed in some detail. A review is given of equipment available on the market today - with some emphasis on automation - which is partly based on information from industry and others involved in research and development. (author)

  11. Solid state radiation dosimetry

    International Nuclear Information System (INIS)

    Moran, P.R.

    1976-01-01

    Important recent developments provide accurate, sensitive, and reliable radiation measurements by using solid state radiation dosimetry methods. A review of the basic phenomena, devices, practical limitations, and categories of solid state methods is presented. The primary focus is upon the general physics underlying radiation measurements with solid state devices

  12. Radon dosimetry for workers: ICRP's approach

    International Nuclear Information System (INIS)

    Marsh, James W.; Laurier, Dominique; Tirmarche, Margot

    2017-01-01

    The International Commission on Radiological Protection (ICRP) has recently published two reports on radon exposure; Publication 115 on lung cancer risks from radon and radon progeny and Publication 126 on radiological protection against radon exposure. A specific graded approach for the control of radon in workplaces is recommended where a dose assessment is required in certain situations. In its forthcoming publication on Occupational Intakes of Radionuclides (OIR) document, Part 3, effective dose coefficients for radon and thoron will be provided. These will be calculated using ICRP reference biokinetic and dosimetric models. Sufficient information and dosimetric data will be given so that site-specific dose coefficients can be calculated based on measured aerosol parameter values. However, ICRP will recommend a single dose coefficient of 12 mSv per working level month (WLM) for inhaled radon progeny to be used in most circumstances. This chosen reference value was based on both dosimetry and epidemiological data. In this paper, the application and use of dose coefficients for workplaces are discussed including the reasons for the choice of the reference value. Preliminary results of dose calculations for indoor workplaces and mines are presented. The paper also briefly describes the general approach for the management of radon exposure in workplaces based both on ICRP recommendations and the European directive (2013/59/EURATOM). (authors)

  13. The work of committee 2 of ICRP on internal dosimetry

    International Nuclear Information System (INIS)

    Stather, J. W.

    2007-01-01

    Over the last few years Committee 2 of ICRP has been responsible for preparing a series of publications giving dose coefficients for intakes of radionuclides by members of the public. The last report in this series covers doses to the offspring in mothers' milk and should be issued in 2005. The emphasis of work on internal dosimetry is now concerned with occupational exposure. It is intended to replace Publications 30 and 68 that give biokinetic data and dose coefficients for intakes of radionuclides and Publications 54 and 78 that give information for bioassay interpretation, with a single series of publications. The first report of the series is expected to cover radionuclides of the elements addressed in the publications on dose coefficients for members of the public. It will also take into account new recommendations from the Commission. Subsequent publications will cover additional elements. A supporting Guidance Document is also being developed that will give more comprehensive advice on the interpretation of bioassay data. The need for this document was identified following recent interlaboratory comparisons that have shown wide variations in the way monitoring data can be interpreted in different laboratories. (authors)

  14. Criticality accident dosimetry with ESR spectroscopy.

    Science.gov (United States)

    d'Errico, F; Fattibene, P; Onori, S; Pantaloni, M

    1996-01-01

    The suitability of the ESR alanine and sugar detectors for criticality accident dosimetry was experimentally investigated during an intercomparison of dosimetry techniques. Tests were performed irradiating detectors both free-in-air and on-phantom during controlled critcality excursions at the SILENE reactor in Valduc, France. Several grays of absorbed dose were imparted in neutron gamma-ray fields of various relative intensities and spectral distributions. Analysed results confirmed the potential of these systems which can immediately provide an acute dose assessment with an average underestimate of 30%in the various fields. This performance allows for the screening of severely exposed individuals and meets the IAEA recommendations on the early estimate of accident absorbed doses.

  15. European protocol for neutron dosimetry for external beam therapy

    International Nuclear Information System (INIS)

    Broerse, J.J.; Mijnheer, B.J.; Williams, J.R.

    1981-01-01

    The paper attempts to serve the needs of European centres participating in the High LET Therapy Project Group set up under the sponsorship of The European Organization for Research on Treatment of Cancer, to promote cooperation between physicists involved in fast neutron therapy and establish a common basis for neutron dosimetry. Differences in dosimetry procedures between European and American Groups are indicated if relevant. The subject is dealt with under the following main headings: principles of dosimetry of neutron fields, dosimetric methods, physical parameters, determination of absorbed dose at a reference point, determination of absorbed dose at any point, check of absorbed dose given to a patient, dosimetry intercomparisons between institutes. There is an ample bibliography. (U.K.)

  16. The physics of small megavoltage photon beam dosimetry.

    Science.gov (United States)

    Andreo, Pedro

    2018-02-01

    The increased interest during recent years in the use of small megavoltage photon beams in advanced radiotherapy techniques has led to the development of dosimetry recommendations by different national and international organizations. Their requirement of data suitable for the different clinical options available, regarding treatment units and dosimetry equipment, has generated a considerable amount of research by the scientific community during the last decade. The multiple publications in the field have led not only to the availability of new invaluable data, but have also contributed substantially to an improved understanding of the physics of their dosimetry. This work provides an overview of the most important aspects that govern the physics of small megavoltage photon beam dosimetry. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Patient skin dosimetry in interventional cardiology in the Czech Republic

    International Nuclear Information System (INIS)

    Sukupova, L.; Novak, L.; Kala, P.; Cervinka, P.; Stasek, J.

    2011-01-01

    In this study, skin dosimetry of patients undergoing interventional cardiology procedures is presented. Three hospitals were included. Two methods were used for skin dosimetry-radiochromic dosimetry films and reconstruction of skin dose distribution based on examination protocol. Maximum skin doses (MSD) obtained from both methods were compared for 175 patients. For patients for whom the film MSD was >1 Gy, the reconstruction MSD differed from the film MSD in the range of ± 50 % for 83 % of patients. For remaining patients, the difference was higher and it was caused by longer fluoroscopy time. For 59 patients for whom the cumulative dose was known, the cumulative dose was compared with the film MSD. Skin dosimetry with radiochromic films is more accurate than the reconstruction method, but films do not include X-ray fields from lateral projections whilst reconstructions do. (authors)

  18. Using track detectors in neutron dosimetry

    International Nuclear Information System (INIS)

    Spurny, F.; Turek, K.

    1977-01-01

    The usage of track detectors of charged particles provides a new possibility of neutron dosimetry. Presented is a comparison of the main dosimetric characteristics of three various types of track detectots of fast neutrons, i.e. glass in the contact with 232 Th; KODAK LR115 cellulose nitrate; MAKROFOL E polycarbonate. Results of studing energy dependences of detectors are presented. Results obtained using phantoms under radiation fields of various sources of complex gamma-neutron radiation are discussed [ru

  19. Proceedings of the recent developments in radiation dosimetry

    International Nuclear Information System (INIS)

    Bhat, Nagesh; Palani Selvan, T.

    2016-01-01

    Whilst 'Dosimetry' in its original sense deals with methods for a quantitative determination of energy deposited in a given medium by directly or indirectly ionizing radiations, the term is better known as a scientific sub-specialty in the fields of health physics and medical physics, where it is the calculation and assessment of the radiation dose received by the human body. Dosimetry is used extensively for radiation protection and is routinely applied to ensure radiological safety of occupational radiation workers. Internal dosimetry due to the ingestion or inhalation of radioactive materials relies on a variety of physiological or imaging techniques. External dosimetry, due to irradiation from an external source is based on measurements with a dosimeter, or inferred from other radiological protection instruments. Radiation dosimetry is one of the important research areas of Department of Atomic Energy (DAE). This research work is centered on the facilities such as nuclear reactors, reprocessing plants, high energy accelerators (research/industry/medical), radiation standards, food processing, radiation technology development, etc. In each of these facilities, radiation field environment is different and the associated dosimetry concepts are different. Papers relevant to INIS are indexed separately

  20. Radiation processing dosimetry - past, present and future

    International Nuclear Information System (INIS)

    McLaughlin, W.L.

    1999-01-01

    Since the two United Nations Conferences were held in Geneva in 1955 and 1958 on the Peaceful Uses of Atomic Energy and the concurrent foundation of the International Atomic Energy Agency in 1957, the IAEA has fostered high-dose dosimetry and its applications. This field is represented in industrial radiation processing, agricultural programmes, and therapeutic and preventative medicine. Such dosimetry is needed specifically for pest and quarantine control and in the processing of medical products, pharmaceuticals, blood products, foodstuffs, solid, liquid and gaseous wastes, and a variety of useful commodities, e.g. polymers, composites, natural rubber and elastomers, packaging, electronic, and automotive components, as well as in radiotherapy. Improvements and innovations of dosimetry materials and analytical systems and software continue to be important goals for these applications. Some of the recent advances in high-dose dosimetry include tetrazolium salts and substituted polydiacetylene as radiochromic media, on-line real-time as well as integrating semiconductor and diamond-detector monitors, quantitative label dosimeters, photofluorescent sensors for broad dose range applications, and improved and simplified parametric and computational codes for imaging and simulating 3D radiation dose distributions in model products. The use of certain solid-state devices, e.g. optical quality LiF, at low (down to 4K) and high (up to 500 K) temperatures, is of interest for materials testing. There have also been notable developments in experimental dose mapping procedures, e.g. 2D and 3D dose distribution analyses by flat-bed optical scanners and software applied to radiochromic and photofluorescent images. In addition, less expensive EPR spectrometers and new EPR dosimetry materials and high-resolution semiconductor diode arrays, charge injection devices, and photostimulated storage phosphors have been introduced. (author)

  1. Development of Probabilistic Internal Dosimetry Computer Code

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Siwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kwon, Tae-Eun [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Jai-Ki [Korean Association for Radiation Protection, Seoul (Korea, Republic of)

    2017-02-15

    Internal radiation dose assessment involves biokinetic models, the corresponding parameters, measured data, and many assumptions. Every component considered in the internal dose assessment has its own uncertainty, which is propagated in the intake activity and internal dose estimates. For research or scientific purposes, and for retrospective dose reconstruction for accident scenarios occurring in workplaces having a large quantity of unsealed radionuclides, such as nuclear power plants, nuclear fuel cycle facilities, and facilities in which nuclear medicine is practiced, a quantitative uncertainty assessment of the internal dose is often required. However, no calculation tools or computer codes that incorporate all the relevant processes and their corresponding uncertainties, i.e., from the measured data to the committed dose, are available. Thus, the objective of the present study is to develop an integrated probabilistic internal-dose-assessment computer code. First, the uncertainty components in internal dosimetry are identified, and quantitative uncertainty data are collected. Then, an uncertainty database is established for each component. In order to propagate these uncertainties in an internal dose assessment, a probabilistic internal-dose-assessment system that employs the Bayesian and Monte Carlo methods. Based on the developed system, we developed a probabilistic internal-dose-assessment code by using MATLAB so as to estimate the dose distributions from the measured data with uncertainty. Using the developed code, we calculated the internal dose distribution and statistical values (e.g. the 2.5{sup th}, 5{sup th}, median, 95{sup th}, and 97.5{sup th} percentiles) for three sample scenarios. On the basis of the distributions, we performed a sensitivity analysis to determine the influence of each component on the resulting dose in order to identify the major component of the uncertainty in a bioassay. The results of this study can be applied to various

  2. Development of Probabilistic Internal Dosimetry Computer Code

    International Nuclear Information System (INIS)

    Noh, Siwan; Kwon, Tae-Eun; Lee, Jai-Ki

    2017-01-01

    Internal radiation dose assessment involves biokinetic models, the corresponding parameters, measured data, and many assumptions. Every component considered in the internal dose assessment has its own uncertainty, which is propagated in the intake activity and internal dose estimates. For research or scientific purposes, and for retrospective dose reconstruction for accident scenarios occurring in workplaces having a large quantity of unsealed radionuclides, such as nuclear power plants, nuclear fuel cycle facilities, and facilities in which nuclear medicine is practiced, a quantitative uncertainty assessment of the internal dose is often required. However, no calculation tools or computer codes that incorporate all the relevant processes and their corresponding uncertainties, i.e., from the measured data to the committed dose, are available. Thus, the objective of the present study is to develop an integrated probabilistic internal-dose-assessment computer code. First, the uncertainty components in internal dosimetry are identified, and quantitative uncertainty data are collected. Then, an uncertainty database is established for each component. In order to propagate these uncertainties in an internal dose assessment, a probabilistic internal-dose-assessment system that employs the Bayesian and Monte Carlo methods. Based on the developed system, we developed a probabilistic internal-dose-assessment code by using MATLAB so as to estimate the dose distributions from the measured data with uncertainty. Using the developed code, we calculated the internal dose distribution and statistical values (e.g. the 2.5 th , 5 th , median, 95 th , and 97.5 th percentiles) for three sample scenarios. On the basis of the distributions, we performed a sensitivity analysis to determine the influence of each component on the resulting dose in order to identify the major component of the uncertainty in a bioassay. The results of this study can be applied to various situations. In cases

  3. Applied physics of external radiation exposure dosimetry and radiation protection

    CERN Document Server

    Antoni, Rodolphe

    2017-01-01

    This book describes the interaction of living matter with photons, neutrons, charged particles, electrons and ions. The authors are specialists in the field of radiation protection. The book synthesizes many years of experiments with external radiation exposure in the fields of dosimetry and radiation shielding in medical, industrial and research fields. It presents the basic physical concepts including dosimetry and offers a number of tools to be used by students, engineers and technicians to assess the radiological risk and the means to avoid them by calculating the appropriate shields. The theory of radiation interaction in matter is presented together with empirical formulas and abacus. Numerous numerical applications are treated to illustrate the different topics. The state of the art in radiation protection and dosimetry is presented in detail, especially in the field of simulation codes for external exposure to radiation, medical projects and advanced research. Moreover, important data spread in differ...

  4. Modern methods of personnel dosimetry

    International Nuclear Information System (INIS)

    Kraus, W.; Herrmann, D.; Kiesewetter, W.

    The physical properties of radiation detectors for personnel dosimetry are described and compared. The suitability of different types of dosimeters for operational and central monitoring of normal occupational exposure, for accident and catastrophe dosimetry and for background and space-flight dosimetry is discussed. The difficulties in interpreting the dosimeter reading with respect to the dose in individual body organs are discussed briefly. 430 literature citations (up to Spring 1966) are given

  5. The dosimetry of ionizing radiation

    CERN Document Server

    1990-01-01

    A continuation of the treatise The Dosimetry of Ionizing Radiation, Volume III builds upon the foundations of Volumes I and II and the tradition of the preceeding treatise Radiation Dosimetry. Volume III contains three comprehensive chapters on the applications of radiation dosimetry in particular research and medical settings, a chapter on unique and useful detectors, and two chapters on Monte Carlo techniques and their applications.

  6. Study of the influence of radionuclide biokinetics on in vivo counting using voxel phantoms

    International Nuclear Information System (INIS)

    Lamart, St.

    2008-10-01

    The in vivo measurement is an efficient method to estimate the retention of activity in case of internal contamination. However, it is currently limited by the use of physical phantoms for the calibration, not enabling to reproduce neither the morphology of the measured person nor the actual distribution of the contamination. The current method of calibration therefore leads to significant systematic uncertainties on the quantification of the contamination. To improve the in vivo measurement, the Laboratory of Internal Dose Assessment (LEDI, IRSN) has developed an original numerical calibration method with the OEDIPE software. It is based on voxel phantoms created from the medical images of persons, and associated with the MCNPX Monte Carlo code of particle transport. The first version of this software enabled to model simple homogeneous sources and to better estimate the systematic uncertainties in the lung counting of actinides due to the detector position and to the heterogeneous distribution of activity inside the lungs. However, it was not possible to take into account the dynamic feature, and often heterogeneous distribution between body organs and tissues of the activity. Still, the efficiency of the detection system depends on the distribution of the source of activity. The main purpose of the thesis work is to answer to the question: what is the influence of the biokinetics of the radionuclides on the in vivo counting? To answer it, it was necessary to deeply modify OEDIPE. This new development enabled to model the source of activity more realistically from the reference biokinetic models defined by the ICRP. The first part of the work consisted in developing the numerical tools needed to integrate the biokinetics in OEDIPE. Then, a methodology was developed to quantify its influence on the in vivo counting from the results of simulations. This method was carried out and validated on the model of the in vivo counting system of the LEDI. Finally, the

  7. Biokinetic behavior of Tc in the red abalone, Haliotis rufescens: a reassessment

    International Nuclear Information System (INIS)

    Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

    1981-01-01

    The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments on other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalone exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by the abalone following a single feeding of labeled macroalga, Nereocystis pyrifera, is high (approx. 45%) and loss kinetics are similar to those observed following direct uptake from seawater

  8. Nanomaterial translocation - the biokinetics, tissue accumulation, toxicity and fate of materials in secondary organs

    DEFF Research Database (Denmark)

    Kermanizadeh, Ali; Balharry, Dominique; Wallin, Håkan

    2015-01-01

    into the toxicity posed by the NMs in these secondary organs is expanding due to the realisation that some materials may reach and accumulate in these target sites. The translocation to secondary organs includes, but is not limited to, the hepatic, central nervous, cardiovascular and renal systems. Current data...... dioxide and quantum dots) or fast (e.g. zinc oxide) solubility. The translocation of NMs following intratracheal, intranasal and pharyngeal aspiration is higher (up to 10% of administered dose), however the relevance of these routes for risk assessment is questionable. Uptake of the materials from....... For toxicological and risk evaluation, further information on the toxicokinetics and persistence of NMs is crucial. The overall aim of this review is to outline the data currently available in the literature on the biokinetics, accumulation, toxicity and eventual fate of NMs in order to assess the potential risks...

  9. Biokinetics of carbohydrate and lipid matabolism in normal laying hen; pt. 3

    International Nuclear Information System (INIS)

    Chiang, Y.H.; Riis, P.M.

    1979-01-01

    The radiochemical purity of sup(14)C(U)-glucose solution to be injected to normal laying hen was investigated for studying biokinetics of carbohydrate and lipid metabolism. The liquid scintillation counter was employed for determining the activity of carbon-14. The barium hydroxide and zinc sulfate were adopted to precipitate the protein in the solution. The glucose content in the solution was observed as 0.912 mg per ml. applying Hultman's method. The specific activity of sup(14)C(U)-glucose solution was known as 31.3 nCi/mg glucose. The glucose pentaacetate was synthesized to isolate the pure glucose from the solution. The specific activity of pure glucose was measured as 28.5 nCi/mg glucose. Therefore, it was known that the radiochemical purity of the solution was 82.7%. (Author)

  10. Critical review of membrane bioreactor models--part 1: biokinetic and filtration models.

    Science.gov (United States)

    Naessens, W; Maere, T; Nopens, I

    2012-10-01

    Membrane bioreactor technology exists for a couple of decades, but has not yet overwhelmed the market due to some serious drawbacks of which operational cost due to fouling is the major contributor. Knowledge buildup and optimisation for such complex systems can significantly benefit from mathematical modelling. In this paper, the vast literature on modelling MBR biokinetics and filtration is critically reviewed. It was found that models cover the wide range of empirical to detailed mechanistic descriptions and have mainly been used for knowledge development and to a lesser extent for system optimisation/control. Moreover, studies are still predominantly performed at lab or pilot scale. Trends are discussed, knowledge gaps identified and interesting routes for further research suggested. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

    Energy Technology Data Exchange (ETDEWEB)

    Beasley, T.M.; Lorz, H.V.; Gonor, J.J. (Oregon State Univ., Newport (USA). Marine Science Center)

    1982-10-01

    The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater.

  12. Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

    Energy Technology Data Exchange (ETDEWEB)

    Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

    1982-10-01

    The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labelled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, is approximately 45% and loss kinetics are similar to those observed following direct uptake from seawater.

  13. Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

    International Nuclear Information System (INIS)

    Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

    1982-01-01

    The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater. (author)

  14. Selenium-75 and technetium-95m biokinetics in rats at different physiological states

    International Nuclear Information System (INIS)

    Archimbaud, Yves; Grillon, Gerard; Poncy, Jean-Luc; Masse, Roland

    1992-06-01

    Selenium 79 ( 79 Se) and technetium ( 99 Tc), beta emitters, components of nuclear wastes, may increase the dose equivalent to members of the public. Data used by ICRP show that there is relatively little information on Te and Se biokinetics at different physiologic stages. Retention was almost equivalent for young, male adult and pregnant rat. Selenium was concentrated in the testis, the kidneys, the liver and the spleen as technetium was in the skin, the thyroid and the kidneys. The biological half-time for Se and Te was respectively 20 and 41 days for pregnant rats, 33 and 15 days for young rats. Placental transfer per one fetus was 0.56% of the initial activity for Te and 1.27% for Se. These data point out the eventually high doses delivered to the skin for Te and to the testis for Se. They may be taken into consideration in estimating risk by humans at different stages of life [fr

  15. Interlaboratory niobium dosimetry comparison

    International Nuclear Information System (INIS)

    Wille, P.

    1980-01-01

    For an interlaboratory comparison of neutron dosimetry using niobium the 93 sup(m)Nb activities of irradiated niobium monitors were measured. This work was performed to compare the applied techniques of dosimetry with Nb in different laboratories. The niobium monitors were irradiated in the fast breeder EBRII, USA and the BR2, Belgium. The monitors were dissolved and several samples were prepared. Their niobium contents were determined by the 94 Nb-count rates. since the original specific count rate was known. The KX radiations of the 93 sup(m)Nb of the samples and of a calibrated Nb-foil were compared. This foil was measured by PTB, Braunschweig and CBNM, Geel, which we additionally compared with the KX radiation of 88 Sr produced by a thin 88 Y source from a 88 Y-standard solution (PTB). (orig.) [de

  16. Neutron beam measurement dosimetry

    International Nuclear Information System (INIS)

    Amaro, C.R.

    1995-01-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR

  17. Hanford External Dosimetry Program

    International Nuclear Information System (INIS)

    Fix, J.J.

    1990-10-01

    This document describes the Hanford External Dosimetry Program as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) and its Hanford contractors. Program services include administrating the Hanford personnel dosimeter processing program and ensuring that the related dosimeter data accurately reflect occupational dose received by Hanford personnel or visitors. Specific chapters of this report deal with the following subjects: personnel dosimetry organizations at Hanford and the associated DOE and contractor exposure guidelines; types, characteristics, and procurement of personnel dosimeters used at Hanford; personnel dosimeter identification, acceptance testing, accountability, and exchange; dosimeter processing and data recording practices; standard sources, calibration factors, and calibration processes (including algorithms) used for calibrating Hanford personnel dosimeters; system operating parameters required for assurance of dosimeter processing quality control; special dose evaluation methods applied for individuals under abnormal circumstances (i.e., lost results, etc.); and methods for evaluating personnel doses from nuclear accidents. 1 ref., 14 figs., 5 tabs

  18. WIPP radiation dosimetry program

    International Nuclear Information System (INIS)

    Wu, C.F.

    1991-01-01

    Radiation dosimetry is the process by which various measurement results and procedures are applied to quantify the radiation exposure of an individual. Accurate and precise determination of radiation dose is a key factor to the success of a radiation protection program. The Waste Isolation Pilot Plant (WIPP), a Department of Energy (DOE) facility designed for permanent repository of transuranic wastes in a 2000-foot-thick salt bed 2150 feet underground, has established a dosimetry program developed to meet the requirements of DOE Order 5480.11, ''Radiation Protection for Occupational Workers''; ANSI/ASME NQA-1, ''Quality Assurance Program Requirements for Nuclear Facilities''; DOE Order 5484.1, ''Environmental Protection, Safety, and Health Protection Information Reporting Requirements''; and other applicable regulations

  19. Accuracy of internal dose calculations with special consideration of radiopharmaceutical biokinetics

    International Nuclear Information System (INIS)

    Roedler, H.D.

    1981-01-01

    The individual steps of internal dose calculation, including the models and data used, as well as error considerations, are analysed following a short synopsis on the formalism of absorbed dose calculation. The mean dose in a target tissue depends on the administered activity, the residence time of the activity in the source tissues and the mean absorbed dose in the target tissue per transformation in a source tissue. Usually, a standard dosage is applied in radionuclide studies except in children. Actually administered and nomial activities generally differ by less than 10%. For the purpose of internal dose calculation, the biokinetics of a radiopharmaceutical are reflected in the residence times for the individual source tissues. The methods and the evaluation of measurements of biodistribution and retention data are discussed. The extrapolation of animal data to man is treated in some detail, including a survey of the methods used, as well as an attempt for validating these methods. None of these seem to yield more convincing results than the direct transfer of the residence times from animal to man, at least for the two radiopharmaceuticals discussed. The minimum period of measurement to derive residence times for the purpose of dose calculation has been determined as about one physical half-time. Some problems of the dose per transformation to a phantom are presented, including the age- or size-dependence of the internal dose. Organ doses to the phantom, calculated from different apparently reliable sets of biokinetic data, are generally compatible within a factor of 2 to 3, and somatically effective doses are generally compatible within a factor of less than 2

  20. Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat

    International Nuclear Information System (INIS)

    Monleau, M.

    2005-12-01

    Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure. It

  1. Quantitative imaging for clinical dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bardies, Manuel [INSERM U601, 9 Quai Moncousu, 44093 Nantes (France)]. E-mail: manu@nantes.inserm.fr; Flux, Glenn [Department of Physics, Royal Marsden NHS Trust, Sutton (United Kingdom); Lassmann, Michael [Department of Nuclear Medicine, Julis-Maximilians University, Wuerzburg (Germany); Monsieurs, Myriam [Department of Health Physics, University of Ghent, 9000 Ghent (Belgium); Savolainen, Sauli [Department of Physical Sciences, University of Helsinki and HUS, Helsinki Medical Imaging Center, Helsinki University Central Hospital (Finland); Strand, Sven-Erik [Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University (Sweden)

    2006-12-20

    Patient-specific dosimetry in nuclear medicine is now a legal requirement in many countries throughout the EU for targeted radionuclide therapy (TRT) applications. In order to achieve that goal, an increased level of accuracy in dosimetry procedures is needed. Current research in nuclear medicine dosimetry should not only aim at developing new methods to assess the delivered radiation absorbed dose at the patient level, but also to ensure that the proposed methods can be put into practice in a sufficient number of institutions. A unified dosimetry methodology is required for making clinical outcome comparisons possible.

  2. Sixth symposium on neutron dosimetry

    International Nuclear Information System (INIS)

    1987-01-01

    This booklet contains all abstracts of papers presented in 13 sessions. Main topics: Cross sections and Kerma factors; analytical radiobiology; detectors for personnel monitoring; secondary charged particles and microdosimetric basis of q-value for neutrons; personnel dosimetry; concepts for radiation protection; ambient monitoring; TEPC and ion chambers in radiation protection; beam dosimetry; track detectors (CR-39); dosimetry at biomedical irradiation facilities; health physics at therapy facilities; calibration for radiation protection; devices for beam dosimetry (TLD and miscellaneous); therapy and biomedical irradiation facilities; treatment planning. (HP)

  3. Dosimetry for Crystals Irradiation

    CERN Document Server

    Lecomte, Pierre

    2005-01-01

    Before shipment to CMS, all PbWO4 crystals produced in China are irradiated there with 60 Co , in order to insure that the induced absorption coefficient is within specifications. Acceptance tests at CERNand at ENEA also include irradiation with gamma rays from 60 Co sources. There were initially discrepancies in quoted doses and doserates as well as in induced absorption coefficients. The present work resolves the discrepancies in irradiation measurements and defines common dosimetry methods for consistency checks between irradiation facilities.

  4. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    1999-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact the Individual Dosimetry ServiceWe inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period JANUARY/FEBRUARY will be available from their usual dispatchers on Monday the third of January 2000.Please have your films changed:before the 12 January.The colour of the dosimeter valid in JANUARY/FEBRUARY is WHITE.

  5. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact the Individual Dosimetry Service.We inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period MARCH/APRIL will be available from their usual dispatchers on the third of March 2000.Please have your films changed before the 13th of March.The colour of the dosimeter valid in MARCH/APRIL is BLUE.

  6. Personal radon daughter dosimetry

    International Nuclear Information System (INIS)

    Stocker, H.

    1979-12-01

    The conventional means of radon daughter exposure estimatikn for uranium miners in Canada is by grab sampling and time weighting. Personal dosimetry is a possible alternative method with its own advantages and limitations. The author poses basic questions with regard to two methods of radon daughter detection, thermoluminescent chips and track-etch film. An historical review of previous and current research and development programs in Canada and in other countries is presented, as are brief results and conclusions of each dosimeter evaluation

  7. Personnel radiation dosimetry

    International Nuclear Information System (INIS)

    1987-01-01

    The book contains the 21 technical papers presented at the Technical Committee Meeting to Elaborate Procedures and Data for the Intercomparison of Personnel Dosimeters organizaed by the IAEA on 22-26 April 1985. A separate abstract was prepared for each of these papers. A list of areas in which additional research and development work is needed and recommendations for an IAEA-sponsored intercomparison program on personnel dosimetry is also included

  8. Guide for selection and calibration of dosimetry systems for radiation processing

    International Nuclear Information System (INIS)

    2002-01-01

    This guide covers the basis for selecting and calibrating dosimetry systems used to measure absorbed dose in gamma ray or X-ray fields and in electron beams used for radiation processing. It discusses the types of dosimetry systems that may be employed during calibration or on a routine basis as part of quality assurance in commercial radiation processing of products. This guide also discusses interpretation of absorbed dose and briefly outlines measurements of the uncertainties associated with the dosimetry. The details of the calibration of the analytical instrumentation are addressed in individual dosimetry system standard practices. The absorbed-dose range covered is up to 1 MGy (100 Mrad). Source energies covered are from 0.1 to 50 MeV photons and electrons. This guide should be used along with standard practices and guides for specific dosimetry systems and applications covered in other standards. Dosimetry for radiation processing with neutrons or heavy charged particles is not covered in this guide

  9. Phantom positioning variation in the Gamma Knife® Perfexion dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Nathalia Almeida; Potiens, Maria da Penha Albuquerque [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Saraiva, Crystian [Hospital do Coracao, Sao Paulo, SP (Brazil)

    2015-07-01

    The use of small volume ionization chamber has become required for the dosimetry of equipment that use small radiation fields. A pinpoint ionization chamber is ideal for the dosimetry of a Gamma Knife® Perfexion (GKP) unit. In this work, this chamber was inserted into the phantom, and measurements were performed with the phantom in different positions, in order to verify if the change in the phantom positioning affects the dosimetry of the GKP. Three different phantom positions were performed. The variation in the result is within the range allowed for the dosimetry of a GKP equipment. (author)

  10. Dosimetry: an ARDENT topic

    CERN Multimedia

    CERN Bulletin

    2012-01-01

    The first annual ARDENT workshop took place in Vienna from 20 to 23 November. The workshop gathered together the Early-Stage Researchers (ESR) and their supervisors, plus other people involved from all the participating institutions.   “The meeting, which was organised with the local support of the Austrian Institute of Technology, was a nice opportunity for the ESRs to get together, meet each other, and present their research plans and some preliminary results of their work,” says Marco Silari, a member of CERN Radiation Protection Group and the scientist in charge of the programme. Two full days were devoted to a training course on radiation dosimetry, delivered by renowned experts. The workshop closed with a half-day visit to the MedAustron facility in Wiener Neustadt. ARDENT (Advanced Radiation Dosimetry European Network Training) is a Marie Curie ITN project funded under EU FP7 with €4 million. The project focuses on radiation dosimetry exploiting se...

  11. Dosimetry in dentistry.

    Science.gov (United States)

    Asha, M L; Chatterjee, Ingita; Patil, Preeti; Naveen, S

    2015-01-01

    The purpose of this paper was to review various dosimeters used in dentistry and the cumulative results of various studies done with various dosimeters. Several relevant PubMed indexed articles from 1999 to 2013 were electronically searched by typing "dosimeters", "dosimeters in dentistry", "properties of dosimeters", "thermoluminescent and optically stimulated dosimeters", "recent advancements in dosimetry in dentistry." The searches were limited to articles in English to prepare a concise review on dental dosimetry. Titles and abstracts were screened, and articles that fulfilled the criteria of use of dosimeters in dental applications were selected for a full-text reading. Article was divided into four groups: (1) Biological effects of radiation, (2) properties of dosimeters, (3) types of dosimeters and (4) results of various studies using different dosimeters. The present review on dosimetry based on various studies done with dosimeters revealed that, with the advent of radiographic technique the effective dose delivered is low. Therefore, selection of radiological technique plays an important role in dental dose delivery.

  12. Dosimetry in life sciences

    International Nuclear Information System (INIS)

    1975-01-01

    The uses of radiation in medicine and biology have grown in scope and diversity to make the Radiological Sciences a significant factor in both research and medical practice. Of critical importance in the applications and development of biomedical and radiological techniques is the precision with which the dose may be determined at all points of interest in the absorbing medium. This has developed as a result of efficacy of investigations in clinical radiation therapy, concern for patient safety and diagnostic accuracy in diagnostic radiology and the advent of clinical trials and research into the use of heavily ionizing radiations in biology and medicine. Since the last IAEA Symposium on Dosimetry Techniques applied to Agriculture, Industry, Biology and Medicine, held in Vienna in 1972, it has become increasingly clear that advances in the techniques and hardware of biomedical dosimetry have been rapid. It is for these reasons that this symposium was organized in a concerted effort to focus on the problems, developments and areas of further research in dosimetry in the Life Sciences. (author)

  13. Dosimetry in life sciences

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-06-15

    The uses of radiation in medicine and biology have grown in scope and diversity to make the Radiological Sciences a significant factor in both research and medical practice. Of critical importance in the applications and development of biomedical and radiological techniques is the precision with which the dose may be determined at all points of interest in the absorbing medium. This has developed as a result of efficacy of investigations in clinical radiation therapy, concern for patient safety and diagnostic accuracy in diagnostic radiology and the advent of clinical trials and research into the use of heavily ionizing radiations in biology and medicine. Since the last IAEA Symposium on Dosimetry Techniques applied to Agriculture, Industry, Biology and Medicine, held in Vienna in 1972, it has become increasingly clear that advances in the techniques and hardware of biomedical dosimetry have been rapid. It is for these reasons that this symposium was organized in a concerted effort to focus on the problems, developments and areas of further research in dosimetry in the Life Sciences. (author)

  14. What is New in Internal Dosimetry and Monitoring?

    Energy Technology Data Exchange (ETDEWEB)

    Henrichs, K. [Siemens AG, Corporate Radiation Safety and Dangerous Goods Transport, Munich (Germany); Nosske, D. [Federal Office for Radiation Protection, Neuherberg (Germany)

    2006-07-01

    This file is divided in two parts:the first one concerns the progress in internal dosimetry. This part gives an overview on new model developments by ICRP, the series of age dependent doses for members of the public was continued by biokinetic and dosimetric models for the embryo and foetus due to activity intake by the mother (ICRP,2001) and for the infant via consumption of mother's milk after activity intake by the mother (ICRP, 2004). In both publications dose coefficients for the embryo and foetus as well the infant were given for various intake scenarios by mother. The present model development work of ICRP is a revision of Publications 30, 54, 68, and 78 based on the new human Alimentary tract model (H.A.T.M.) of ICRP (ICRP, 2006), a revision of absorption parameters for the human respiratory tract model (ICRP, 1994a), new systemic models as well as new dosimetric parameters derived with new Voxel models for the reference male and female adult. The second part concerns the progress in workers monitoring for radionuclide intake. The initiatives to improve the situation are the guidelines published by the International Atomic Energy Agency (2004), giving guidance for the assessment of occupational exposures due to intakes of radionuclides, research project funded by the European Commission: the objective of O.M.I.N.E.X. was the improvement of monitoring programmes, taking into account the uncertainties of biokinetic models and data, the programme I.D.E.A. tried to improve measuring techniques and I.D.E.A.S derives rules for the evaluation of measured activity values in terms of exposure. Standardization projects by the International Standardization Organization I.S.O.: I.S.O. (2001) published a standard defining the requirements for bioassay laboratories, which will soon followed by a second part giving the rationale behind these rules., presently the final version (I.S.O. 2005) of a standard is circulating among the I.S.O. member states which guidance on

  15. What is New in Internal Dosimetry and Monitoring?

    International Nuclear Information System (INIS)

    Henrichs, K.; Nosske, D.

    2006-01-01

    This file is divided in two parts:the first one concerns the progress in internal dosimetry. This part gives an overview on new model developments by ICRP, the series of age dependent doses for members of the public was continued by biokinetic and dosimetric models for the embryo and foetus due to activity intake by the mother (ICRP,2001) and for the infant via consumption of mother's milk after activity intake by the mother (ICRP, 2004). In both publications dose coefficients for the embryo and foetus as well the infant were given for various intake scenarios by mother. The present model development work of ICRP is a revision of Publications 30, 54, 68, and 78 based on the new human Alimentary tract model (H.A.T.M.) of ICRP (ICRP, 2006), a revision of absorption parameters for the human respiratory tract model (ICRP, 1994a), new systemic models as well as new dosimetric parameters derived with new Voxel models for the reference male and female adult. The second part concerns the progress in workers monitoring for radionuclide intake. The initiatives to improve the situation are the guidelines published by the International Atomic Energy Agency (2004), giving guidance for the assessment of occupational exposures due to intakes of radionuclides, research project funded by the European Commission: the objective of O.M.I.N.E.X. was the improvement of monitoring programmes, taking into account the uncertainties of biokinetic models and data, the programme I.D.E.A. tried to improve measuring techniques and I.D.E.A.S derives rules for the evaluation of measured activity values in terms of exposure. Standardization projects by the International Standardization Organization I.S.O.: I.S.O. (2001) published a standard defining the requirements for bioassay laboratories, which will soon followed by a second part giving the rationale behind these rules., presently the final version (I.S.O. 2005) of a standard is circulating among the I.S.O. member states which guidance on the

  16. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684; Dosimetrie pour la radioprotection en milieu medical - rapport du groupe de travail n. 9 du European radiation dosimetry group (EURADOS) - coordinated netword for radiation dosimetry (CONRAD - contrat CE fp6-12684)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  17. Estimation of parameters biokinetics from the resolution of a model compartment for I-131. Application to a patient with thyroid carcinoma hemodialysis

    International Nuclear Information System (INIS)

    Garcia, R.; Jimenez Feltstrom, D.; Luis dimon, F. J.; Sanchez Carmona, G.; Herrador Cordoba, M.

    2013-01-01

    This work aims to define a biokinetic model for the I-131, and solve it for different conditions of the patient or person affected (normal, with cancer of the thyroid or hyperthyroid). Solve the model in the case of a patient treated with I-131 for ablation of thyroid remnants with undergoing renal insufficiency and hemodialysis . Get the parameters Biokinetic this model for different situations. (Author)

  18. Sci-Sat AM: Radiation Dosimetry and Practical Therapy Solutions - 05: Not all geometries are equivalent for magnetic field Fano cavity tests

    Energy Technology Data Exchange (ETDEWEB)

    Malkov, Victor N.; Rogers, David W.O. [Carleton University (Canada)

    2016-08-15

    The coupling of MRI and radiation treatment systems for the application of magnetic resonance guided radiation therapy necessitates a reliable magnetic field capable Monte Carlo (MC) code. In addition to the influence of the magnetic field on dose distributions, the question of proper calibration has arisen due to the several percent variation of ion chamber and solid state detector responses in magnetic fields when compared to the 0 T case (Reynolds et al., Med Phys, 2013). In the absence of a magnetic field, EGSnrc has been shown to pass the Fano cavity test (a rigorous benchmarking tool of MC codes) at the 0.1 % level (Kawrakow, Med.Phys, 2000), and similar results should be required of magnetic field capable MC algorithms. To properly test such developing MC codes, the Fano cavity theorem has been adapted to function in a magnetic field (Bouchard et al., PMB, 2015). In this work, the Fano cavity test is applied in a slab and ion-chamber-like geometries to test the transport options of an implemented magnetic field algorithm in EGSnrc. Results show that the deviation of the MC dose from the expected Fano cavity theory value is highly sensitive to the choice of geometry, and the ion chamber geometry appears to pass the test more easily than larger slab geometries. As magnetic field MC codes begin to be used for dose simulations and correction factor calculations, care must be taken to apply the most rigorous Fano test geometries to ensure reliability of such algorithms.

  19. The work of committee 2 of ICRP on internal dosimetry

    International Nuclear Information System (INIS)

    Stather, J.W.

    2005-01-01

    Full text: Over the last few years the Task Group of Committee 2 of ICRP on Internal Dosimetry (INDOS), in conjunction with the Task Group on Dose Calculations (DOCAL), has prepared a series of publications that have given dose coefficients for intakes of radionuclides by infants, children and adults. The most recent publications have been Publication 88 that gives doses to the embryo, fetus and newborn child from intakes of radionuclides by the mother and Publication 94 that will give doses to the newborn child from intakes of radionuclides in mothers' milk. These documents have completed the programme of work of Committee 2 on dose coefficients for members of the public. The emphasis of work on internal dosimetry by Committee 2 is now concerned with occupational exposure. This is will take into account recent advice from ICRP, including the new 2005 Recommendations of ICRP which are expected to provide revised tissue weighting factors for the calculation of effective dose. In addition ICRP has issued Publication 89 on Basic Anatomical and Physiological Data for use in Radiological Protection and in addition will have published a new Human Alimentary Tract Model (HATM). It will have implemented a human phantom for dose calculations based upon medical imaging data and updated radionuclide decay data; superseding Publication 38. In addition, the systemic models for a number of elements are being revised to take account of more recent data, and the lung clearance characteristics of a wide range of compounds relevant to occupational exposure are being reviewed. It is intended to replace Publications 30 and 68 that give biokinetic data and dose coefficients for intakes of radionuclides and Publications 54 and 78 that give information for bioassay interpretation, with a single series of publications. This series will cover both dosimetry and data for bioassay interpretation. The first report will cover radionuclides of the 31 elements covered in the series of

  20. Eleventh DOE workshop on personnel neutron dosimetry

    International Nuclear Information System (INIS)

    1991-01-01

    Since its formation, the Office of Health (EH-40) has stressed the importance of the exchange of information related to and improvements in neutron dosimetry. This Workshop was the eleventh in the series sponsored by the Department of Energy (DOE). It provided a forum for operational personnel at DOE facilities to discuss current issues related to neutron dosimetry and for leading investigators in the field to discuss promising approaches for future research. A total of 26 papers were presented including the keynote address by Dr. Warren K. Sinclair, who spoke on, ''The 1990 Recommendations of the ICRP and their Biological Background.'' The first several papers discussed difficulties in measuring neutrons of different energies and ways of compensating or deriving correction factors at individual facilities. Presentations were also given by the US Navy and Air Force. Current research in neutron dosimeter development was the subject of the largest number of papers. These included a number on the development of neutron spectrometers

  1. Development of pregnant female, hybrid voxel-mathematical models and their application to the dosimetry of applied magnetic and electric fields at 50 Hz

    International Nuclear Information System (INIS)

    Dimbylow, Peter

    2006-01-01

    This paper describes the development of 2 mm resolution hybrid voxel-mathematical models of the pregnant female. Mathematical models of the developing foetus at 8-, 13-, 26- and 38-weeks of gestation were converted into voxels and combined with the adult female model, NAOMI. This set of models was used to calculate induced current densities and electric fields in the foetus from applied 50 Hz magnetic and electric fields. The influence of foetal tissue conductivities was investigated and implications for electromagnetic field guidelines discussed

  2. Boron dose determination for BNCT using Fricke and EPR dosimetry

    International Nuclear Information System (INIS)

    Wielopolski, L.; Ciesielski, B.

    1995-01-01

    In Boron Neutron Capture Therapy (BNCT) the dominant dose delivered to the tumor is due to α and 7 Li charged particles resulting from a neutron capture by 10 B and is referred to herein as the boron dose. Boron dose is directly attributable to the following two independent factors, one boron concentration and the neutron capture energy dependent cross section of boron, and two the energy spectrum of the neutrons that interact with boron. The neutron energy distribution at a given point is dictated by the incident neutron energy distribution, the depth in tissue, geometrical factors such as beam size and patient's dimensions. To account for these factors can be accommodated by using Monte Carlo theoretical simulations. However, in conventional experimental BNCT dosimetry, e.g., using TLDs or ionization chambers, it is only possible to estimate the boron dose. To overcome some of the limitations in the conventional dosimetry, modifications in ferrous sulfate dosimetry (Fricke) and Electron Paramagnetic Resonance (EPR) dosimetry in alanine, enable to measure specifically boron dose in a mixed gamma neutron radiation fields. The boron dose, in either of the dosimeters, is obtained as a difference between measurements with boronated and unboronated dosimeters. Since boron participates directly in the measurements, the boron dosimetry reflects the true contribution, integral of the neutron energy spectrum with boron cross section, of the boron dose to the total dose. Both methods are well established and used extensively in dosimetry, they are presented briefly here

  3. EURADOS. A success story for European cooperation in the dosimetry of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ruehm, Werner [Helmholtz Zentrum Muenchen, Neuherberg (Germany). German Research Center for Environmental Health (GMBH); Schuhmacher, Helmut [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    2017-10-01

    EURADOS (European Radiation Dosimetry Group) is a European research platform aiming at the promotion of research and development and European cooperation in the field of the dosimetry of ionizing radiation (www.eurados.org). Initially founded in 1982, it was established in 2008 as a non-profit registered society under German law and is currently based in Neuherberg, Germany.

  4. Activity Of EURADOS In Environmental Solid State Dosimetry

    International Nuclear Information System (INIS)

    Ranogajec-Komor, M.; Duch, M. A.; Haninger, T.

    2015-01-01

    Working Group 3 (WG3) of the European Radiation Dosimetry Group (EURADOS) carries out research projects and coordinated activities to advance the scientific understanding of environmental dosimetry and especially to promote the technical development of new methods in environmental monitoring. In this field of dosimetry, the measurement of small additional doses caused by artificial radiation on top of the natural environmental radiation is a challenge. Further, WG3 stimulates the organisation of intercomparison programmes and the definition of standards and recommendations in the field of environmental radiation monitoring (ERM). WG3 has played a significant role in the harmonisation of early warning dosimetry network stations in Europe and has organised 6 EURADOS intercomparison exercises; in which 42 institutions from 19 countries have participated. Today, about 5000 stations provide real-time dose rate data to a database run by the European Commission. Within WG3 a subgroup (S1) on spectrometry system was formed in 2013. Since then, WG3 has been involved in the field of spectrometry systems used both for dosimetric and spectrometric monitoring in the environment. A remarkable result of the WG3 - S1 is that many members contributed to the new European Joint Research Project 'Metrology for radiological early warning networks in Europe' which started in 2014. A second subgroup WG3 - S2 on passive dosimetry in ERM was inaugurated in 2014. To gain an overview of the passive dosimetry practice in ERM, WG3 - S2 decided to collect information by means of a questionnaire which has been send to European dosimetry services. One of the results was the identification of some open questions, problems in ERM (for example terminology, protocol of routine dosimetry, uncertainty assessment) which require clarification for harmonisation of ERM using passive dosimeters. Another result was that there exists a need for intercomparisons. The first intercomparison for passive

  5. In vivo dosimetry with silicon diodes in total body irradiation

    International Nuclear Information System (INIS)

    Oliveira, F.F.; Amaral, L.L.; Costa, A.M.; Netto, T.G.

    2014-01-01

    The aim of this work is the characterization and application of silicon diode detectors for in vivo dosimetry in total body irradiation (TBI) treatments. It was evaluated the diode response with temperature, dose rate, gantry angulations and field size. A maximum response variation of 2.2% was obtained for temperature dependence. The response variation for dose rate and angular was within 1.2%. For field size dependence, the detector response increased with field until reach a saturation region, where no more primary radiation beam contributes for dose. The calibration was performed in a TBI setup. Different lateral thicknesses from one patient were simulated and then the calibration factors were determined by means of maximum depth dose readings. Subsequent to calibration, in vivo dosimetry measurements were performed. The response difference between diode readings and the prescribed dose for all treatments was below 4%. This difference is in agreement as recommended by the International Commission on Radiation Units and Measurements (ICRU), which is ±5%. The present work to test the applicability of a silicon diode dosimetry system for performing in vivo dose measurements in TBI techniques presented good results. These measurements demonstrated the value of diode dosimetry as a treatment verification method and its applicability as a part of a quality assurance program in TBI treatments. - Highlights: ► Characterization of a silicon diode dosimetry system. ► Application of the diodes for in vivo dosimetry in total body irradiation treatments. ► Implementation of in vivo dosimetry as a part of a quality assurance program in radiotherapy

  6. Special workshop on lung dosimetry

    International Nuclear Information System (INIS)

    Fisher, D.R.

    1983-01-01

    A Special Workshop on Lung Dosimetry was convened in Salt Lake City, Utah, on April 21-22, 1982, to stimulate the use of improved radiation dosimetry and to formulate a stronger basis for dose-response relationships for inhaled radionuclides. The two-day workshop was held in conjunction with the 30th Annual Meeting of the Radiation Research Society. Publication is planned

  7. Percentage depth dose calculation accuracy of model based algorithms in high energy photon small fields through heterogeneous media and comparison with plastic scintillator dosimetry.

    Science.gov (United States)

    Alagar, Ananda Giri Babu; Mani, Ganesh Kadirampatti; Karunakaran, Kaviarasu

    2016-01-08

    Small fields smaller than 4 × 4 cm2 are used in stereotactic and conformal treatments where heterogeneity is normally present. Since dose calculation accuracy in both small fields and heterogeneity often involves more discrepancy, algorithms used by treatment planning systems (TPS) should be evaluated for achieving better treatment results. This report aims at evaluating accuracy of four model-based algorithms, X-ray Voxel Monte Carlo (XVMC) from Monaco, Superposition (SP) from CMS-Xio, AcurosXB (AXB) and analytical anisotropic algorithm (AAA) from Eclipse are tested against the measurement. Measurements are done using Exradin W1 plastic scintillator in Solid Water phantom with heterogeneities like air, lung, bone, and aluminum, irradiated with 6 and 15 MV photons of square field size ranging from 1 to 4 cm2. Each heterogeneity is introduced individually at two different depths from depth-of-dose maximum (Dmax), one setup being nearer and another farther from the Dmax. The central axis percentage depth-dose (CADD) curve for each setup is measured separately and compared with the TPS algorithm calculated for the same setup. The percentage normalized root mean squared deviation (%NRMSD) is calculated, which represents the whole CADD curve's deviation against the measured. It is found that for air and lung heterogeneity, for both 6 and 15 MV, all algorithms show maximum deviation for field size 1 × 1 cm2 and gradually reduce when field size increases, except for AAA. For aluminum and bone, all algorithms' deviations are less for 15 MV irrespective of setup. In all heterogeneity setups, 1 × 1 cm2 field showed maximum deviation, except in 6MV bone setup. All algorithms in the study, irrespective of energy and field size, when any heterogeneity is nearer to Dmax, the dose deviation is higher compared to the same heterogeneity far from the Dmax. Also, all algorithms show maximum deviation in lower-density materials compared to high-density materials.

  8. Calibration of hydrodynamic behavior and biokinetics for TOC removal modeling in biofilm reactors under different hydraulic conditions.

    Science.gov (United States)

    Zeng, Ming; Soric, Audrey; Roche, Nicolas

    2013-09-01

    In this study, total organic carbon (TOC) biodegradation was simulated by GPS-X software in biofilm reactors with carriers of plastic rings and glass beads under different hydraulic conditions. Hydrodynamic model by retention time distribution and biokinetic measurement by in-situ batch test served as two significant parts of model calibration. Experimental results showed that TOC removal efficiency was stable in both media due to the enough height of column, although the actual hydraulic volume changed during the variation of hydraulic condition. Simulated TOC removal efficiencies were close to experimental ones with low theil inequality coefficient values (below 0.15). Compared with glass beads, more TOC was removed in the filter with plastic rings due to the larger actual hydraulic volume and lower half saturation coefficient in spite of its lower maximum specific growth rate of biofilm, which highlighted the importance of calibrating hydrodynamic behavior and biokinetics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Intercomparison and biokinetic model validation of radionuclide intake assessment. Report of a co-ordinated research project. 1996-1998

    International Nuclear Information System (INIS)

    1999-03-01

    This TECDOC presents the results of a Co-ordinated Research Project (CRP) on Intercomparison and Biokinetic Model Validation of Radionuclide Intake Assessment, including the conclusions of a Research Co-ordination Meeting held from 6 to 8 July 1998. The present CRP on Intercomparison and Biokinetic Model Validation of Radionuclide Intake Assessment is part of the activities of the IAEA's Occupational Protection programme. The objective of this programme is to promote an internationally harmonized approach for optimizing occupational radiation protection through: the development of guides, within the IAEA's activities for establishing standards for radiation protection, for restricting radiation exposures in the workplace and for applying current occupational radiation protection techniques; and the promotion of application of these guidelines

  10. SU-F-J-100: Standardized Biodistribution Template for Nuclear Medicine Dosimetry Collection and Reporting

    Energy Technology Data Exchange (ETDEWEB)

    Kesner, A [University of Colorado, Anschutz Medical Campus, Aurora, Colorado (United States); Poli, G [International Atomic Energy Agency, Vienna, Vienna (Austria); Beykan, S; Lassman, M [University of Wuerzburg, Wuerzberg, Wuerzberg (Germany)

    2016-06-15

    Purpose: As the field of Nuclear Medicine moves forward with efforts to integrate radiation dosimetry into clinical practice we can identify the challenge posed by the lack of standardized dose calculation methods and protocols. All personalized internal dosimetry is derived by projecting biodistribution measurements into dosimetry calculations. In an effort to standardize organization of data and its reporting, we have developed, as a sequel to the EANM recommendation of “Good Dosimetry Reporting”, a freely available biodistribution template, which can be used to create a common point of reference for dosimetry data. It can be disseminated, interpreted, and used for method development widely across the field. Methods: A generalized biodistribution template was built in a comma delineated format (.csv) to be completed by users performing biodistribution measurements. The template is available for free download. The download site includes instructions and other usage details on the template. Results: This is a new resource developed for the community. It is our hope that users will consider integrating it into their dosimetry operations. Having biodistribution data available and easily accessible for all patients processed is a strategy for organizing large amounts of information. It may enable users to create their own databases that can be analyzed for multiple aspects of dosimetry operations. Furthermore, it enables population data to easily be reprocessed using different dosimetry methodologies. With respect to dosimetry-related research and publications, the biodistribution template can be included as supplementary material, and will allow others in the community to better compare calculations and results achieved. Conclusion: As dosimetry in nuclear medicine become more routinely applied in clinical applications, we, as a field, need to develop the infrastructure for handling large amounts of data. Our organ level biodistribution template can be used as a

  11. Eurados trial performance test for photon dosimetry

    DEFF Research Database (Denmark)

    Stadtmann, H.; Bordy, J.M.; Ambrosi, P.

    2001-01-01

    Within the framework of the EURADOS Action entitled Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation, trial performance tests for whole-body and extremity personal dosemeters were carried out. Photon, beta and neutron dosemeters were considered....... This paper summarises the results of the whole-body photon dosemeter test. Twenty-six dosimetry services from all EU Member States and Switzerland participated. Twelve different radiation fields were used to simulate various workplace irradiation fields. Dose values from 0.4 mSv to 80 mSv were chosen. From...

  12. Aqueous chemical dosimetry

    International Nuclear Information System (INIS)

    Matthews, R.W.

    1982-01-01

    Aqueous chemical dosimetry based on ceric and ferrous sulfate solutions and on a number of fluorescence-induced systems is reviewed. Particular attention is given to the factors affecting the response of these dosimeters to radiation and the corrections necessary for more accurate dosimetry under various irradiation conditions. The effect of cerous and ceric ion, oxygen, and sulfuric acid concentration on the ceric dosimeter is discussed together with the effects of temperature, energy of radiation, degraded energy spectra, and peroxysulfuric acids. Practical aspects of ceric/cerous dosimetry are given. Although ferrous sulfate solution is the most important and widely studied reference dosimeter, general agreement has not been reached on the ''best'' value for the molar extinction coefficient of ferric ions nor on the correction necessary to the G(Fe 3 - ) value for irradiations at temperatures significantly different from 25 0 C. New data are presented which indicate that the larger temperature coefficients given in the literature are more accurate. The ferrous sulfate system has been of great importance in establishing the primary radiolytic yields for 0.4 M sulfuric acid solution; it is shown how the failure to take into account the effect of oxygen and ferrous sulfate concentrations has led to erroneously high estimates of the zero solute concentration values in acid solutions. Some of the methods for extending the dose ranges measurable with ferrous sulfate-based solutions are reviewed. Substances which on irradiation give highly fluorescent products are among the most sensitive aqueous chemical dosimeters. These include benzoate and terephthalate solutions and the more recent coumarin and trimesate solutions. Advantages and disadvantages system are discussed. (author)

  13. Heavy-ion dosimetry

    International Nuclear Information System (INIS)

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained

  14. Individual dosimetry and calibration

    International Nuclear Information System (INIS)

    Hoefert, M.; Nielsen, M.

    1996-01-01

    In 1995 both the Individual Dosimetry and Calibration Sections worked under the condition of a status quo and concentrated fully on the routine part of their work. Nevertheless, the machine for printing the bar code which will be glued onto the film holder and hence identify the people when entering into high radiation areas was put into operation and most of the holders were equipped with the new identification. As far as the Calibration Section is concerned the project of the new source control system that is realized by the Technical Support Section was somewhat accelerated

  15. NRPB patient dosimetry service

    International Nuclear Information System (INIS)

    Shrimpton, P.; Hillier, M.; Bungay, D.; Wall, B.

    1994-01-01

    For nearly 20 years, thermoluminescent dosemeters (TLDs) have been used by NRPB to investigate the doses received by patients undergoing diagnostic examinations with x-rays, and these measurements have formed the basis for national recommendations on patient protection. Monitoring typical levels of patient dose should represent an essential element of routine quality assurance in x-ray departments. In order to promote more widespread measurements in hospitals, NRPB has drawn on a wealth of experience to establish a high-quality service providing TLDs for medical dosimetry by post. (author)

  16. Dosimetry in Radiology

    International Nuclear Information System (INIS)

    Andisco, D.; Blanco, S.; Buzzi, A.E

    2014-01-01

    The steady growth in the use of ionizing radiation in diagnostic imaging requires to maintain a proper management of patient’s dose. Dosimetry in Radiology is a difficult topic to address, but vital for proper estimation of the dose the patient is receiving. The awareness that every day is perceived in our country on these issues is the appropriate response to this problem. This article describes the main dosimetric units used and easily exemplifies doses in radiology through internationally known reference values. (authors) [es

  17. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact their dispatchers to explain their activities for the future, after LEP dismantling in order to be maintained on the regular distribution list at Individual Dosimetry ServiceWe inform all staffs and users under regular dosimetric control that the dosimeters for the monitoring period JULY/AUGUST are available from their usual dispatchers.Please have your films changed before the 10th of July.The colour of the dosimeter valid in JULY/AUGUST is PINK.

  18. Tritium dosimetry and standardization

    International Nuclear Information System (INIS)

    Balonov, M.I.

    1983-01-01

    Actual problem of radiation hygiene such as an evaluation of human irradiation hazard due to a contact with tritium compounds both in industrial and public spheres is under discussion. Sources of tritium release to environment are characterized. Methods of tritium radiation monitoring are discussed. Methods of dosimetry of internal human exposure resulted from tritium compounds are developed on the base of modern representations on metbolism and tritium radiobiological effect. A system of standardization of permissible intake of tritium compounds for personnel and persons of population is grounded. Some protection measures are proposed as applied to tritium overdosage

  19. A study of the dosimetry of small field photon beams used in intensity modulated radiation therapy in inhomogeneous media: Monte Carlo simulations, and algorithm comparisons and corrections

    International Nuclear Information System (INIS)

    Jones, Andrew Osler

    2004-01-01

    There is an increasing interest in the use of inhomogeneity corrections for lung, air, and bone in radiotherapy treatment planning. Traditionally, corrections based on physical density have been used. Modern algorithms use the electron density derived from CT images. Small fields are used in both conformal radiotherapy and IMRT, however, their beam characteristics in inhomogeneous media have not been extensively studied. This work compares traditional and modern treatment planning algorithms to Monte Carlo simulations in and near low-density inhomogeneities. Field sizes ranging from 0.5 cm to 5 cm in diameter are projected onto a phantom containing inhomogeneities and depth dose curves are compared. Comparisons of the Dose Perturbation Factors (DPF) are presented as functions of density and field size. Dose Correction Factors (DCF), which scale the algorithms to the Monte Carlo data, are compared for each algorithm. Physical scaling algorithms such as Batho and Equivalent Pathlength (EPL) predict an increase in dose for small fields passing through lung tissue, where Monte Carlo simulations show a sharp dose drop. The physical model-based collapsed cone convolution (CCC) algorithm correctly predicts the dose drop, but does not accurately predict the magnitude. Because the model-based algorithms do not correctly account for the change in backscatter, the dose drop predicted by CCC occurs farther downstream compared to that predicted by the Monte Carlo simulations. Beyond the tissue inhomogeneity all of the algorithms studied predict dose distributions in close agreement with Monte Carlo simulations. Dose-volume relationships are important in understanding the effects of radiation to the lung. The dose within the lung is affected by a complex function of beam energy, lung tissue density, and field size. Dose algorithms vary in their abilities to correctly predict the dose to the lung tissue. A thorough analysis of the effects of density, and field size on dose to the

  20. MOSFET dosimetry: temperature effects in-vivo

    International Nuclear Information System (INIS)

    Yu, P.K.N.; Cheung, T.; Butson, M.J.; Cancer Services, Wollongong, NSW

    2004-01-01

    Full text: This note investigates temperature effects on dosimetry using a Metal Oxide Semiconductor Field Effect Transistor (MOSFET) for radiotherapy x-ray treatment. This was performed by analysing the dose response and threshold voltage outputs for MOSFET dosimeters as a function of ambient temperature. Results have shown the clinical semiconductor dosimetry system (CSDS) MOSFET provides stable dose measurements with temperatures varying from 15 deg C up to 40 deg C. Thus standard irradiations performed at room temperature can be directly compared to in-vivo dose assessments performed at near body temperature without a temperature correction function. The MOSFET dosimeter threshold voltage varies with temperature and this level is dependant on the dose history of the MOSFET dosimeter. However the variation can be accounted for in the measurement method. For accurate dosimetry the detector should be placed for approximately 60 seconds on a patient to allow thermal equilibrium before measurements are taken with the final reading performed whilst still attached to the patient or conversely left for approximately 120 seconds after removal from the patient if initial readout was measured at room temperature to allow temperature equilibrium to be established. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

  1. Clinical dosimetry in diagnostic and interventional radiology

    International Nuclear Information System (INIS)

    Dimcheva, M.; Sergieva, S.; Jovanovska, A.

    2012-01-01

    Full text: Introduction: Diagnostic and interventional procedures involving x-rays are the most significant contributor to total population dose form man made sources of ionizing radiation. Purpose and aim: X-ray imaging generally covers a diverse range of examination types, many of which are increasing in frequency and technical complexity. Materials and methods: The European Directives 96/29 and 97/43 EURATOM stress the importance of accurate dosimetry and require calibration of all measuring equipment related to application of ionizing radiation in medicine. Results: The paper gives and overview of current system of dosimetry of ionizing radiations that is relevant for metrology and clinical applications. It also reflects recently achieved international harmonization in the field promoted by International Atomic Energy Agency (IAEA). Discussion: Objectives of clinical dose measurements in diagnostic and interventional radiology are multiple, as assessment of equipment performance, or assessment of risk emerging from use of ionizing radiation Conclusion: Therefore, from the clinical point of view, the requirements for dosimeters and procedures to assess dose to standard dosimetry phantoms and patients in clinical diverse modalities, as computed tomography are presented

  2. External dosimetry - Applications to radiation protection

    International Nuclear Information System (INIS)

    Faussot, Alain

    2011-01-01

    Dosimetry is the essential component of radiation protection. It allows to determine by calculation and measurement the absorbed dose value, i.e. the energy amounts deposited in matter by ionizing radiations. It deals also with the irradiation effects on living organisms and with their biological consequences. This reference book gathers all the necessary information to understand and master the external dosimetry and the metrology of ionizing radiations, from the effects of radiations to the calibration of radiation protection devices. The first part is devoted to physical dosimetry and allows to obtain in a rigorous manner the mathematical formalisms leading to the absorbed dose for different ionizing radiation fields. The second part presents the biological effects of ionizing radiations on living matter and the determination of a set of specific radiation protection concepts and data to express the 'risk' to develop a radio-induced cancer. The third part deals with the metrology of ionizing radiations through the standardized study of the methods used for the calibration of radiation protection equipments. Some practical exercises with their corrections are proposed at the end of each chapter

  3. Effects of temperature variation on MOSFET dosimetry

    International Nuclear Information System (INIS)

    Cheung Tsang; Butson, Martin J; Yu, Peter K N

    2004-01-01

    This note investigates temperature effects on dosimetry using a metal oxide semiconductor field effect transistor (MOSFET) for radiotherapy x-ray treatment. This was performed by analysing the dose response and threshold voltage outputs for MOSFET dosimeters as a function of ambient temperature. Results have shown that the clinical semiconductor dosimetry system (CSDS) MOSFET provides stable dose measurements with temperatures varying from 15 deg. C up to 40 deg. C. Thus standard irradiations performed at room temperature can be directly compared to in vivo dose assessments performed at near body temperature without a temperature correction function. The MOSFET dosimeter threshold voltage varies with temperature and this level is dependent on the dose history of the MOSFET dosimeter. However, the variation can be accounted for in the measurement method. For accurate dosimetry, the detector should be placed for approximately 60 s on a patient to allow thermal equilibrium before measurements are taken with the final reading performed whilst still attached to the patient or conversely left for approximately 120 s after removal from the patient if initial readout was measured at room temperature to allow temperature equilibrium to be established. (note)

  4. Absorbed dose to water determination with ionization chamber dosimetry and calorimetry in restricted neutron, photon, proton and heavy-ion radiation fields.

    Science.gov (United States)

    Brede, H J; Greif, K-D; Hecker, O; Heeg, P; Heese, J; Jones, D T L; Kluge, H; Schardt, D

    2006-08-07

    Absolute dose measurements with a transportable water calorimeter and ionization chambers were performed at a water depth of 20 mm in four different types of radiation fields, for a collimated (60)Co photon beam, for a collimated neutron beam with a fluence-averaged mean energy of 5.25 MeV, for collimated proton beams with mean energies of 36 MeV and 182 MeV at the measuring position, and for a (12)C ion beam in a scanned mode with an energy per atomic mass of 430 MeV u(-1). The ionization chambers actually used were calibrated in units of air kerma in the photon reference field of the PTB and in units of absorbed dose to water for a Farmer-type chamber at GSI. The absorbed dose to water inferred from calorimetry was compared with the dose derived from ionometry by applying the radiation-field-dependent parameters. For neutrons, the quantities of the ICRU Report 45, for protons the quantities of the ICRU Report 59 and for the (12)C ion beam, the recommended values of the International Atomic Energy Agency (IAEA) protocol (TRS 398) were applied. The mean values of the absolute absorbed dose to water obtained with these two independent methods agreed within the standard uncertainty (k = 1) of 1.8% for calorimetry and of 3.0% for ionometry for all types and energies of the radiation beams used in this comparison.

  5. Film dosimetry for IMRT: sensitivity corrections

    International Nuclear Information System (INIS)

    Suchowerska, N.; Hoban, P.; Davison, A.; Metcalfe, P.

    2000-01-01

    Full text: The trend towards conformal, dynamic and intensity modulated radiotherapy treatments has furthered the need for true integrating dosimetry. In traditional radiotherapy, film dosimetry is commonly used. The accuracy and reproducibility of film optical density as an indicator of dose, has been associated with several variables. These include the effects of film specific sensitivity, direction of exposure, chemical processing and film scanner sensitivity. In this study, a procedure is developed to account for these variables, with a particular view to film being used as a dosimeter for conformal treatments. An effective sensitometric curve was established by exposing part of a single sheet of film to known doses. All films were processed together and scanned using a DuoscanT1200 transmission scanner, resulting in 12 bit image files. The images were analysed using Osiris software and the results fitted to the modified Williamson equation: P P s (l - 10 αD ) This yields values of α [film sensitivity], and P s [saturation pixel value], allowing individual dosimetry films to be normalised to this sensitometric calibration curve. For validation, a piece of Kodak X Omat-V film was sealed in a head phantom and exposed to a total of 51 IMRT fields, delivered from 6 gantry angles. The rest of the sheet of film was resealed and exposed to four known doses, providing sensitometric data, specific to this exposure. All films were then processed, scanned and analysed as described above. Observed variations in serial films exposed to