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Radiation Protection Dosimetry

Josineide Marques do Nascimento Santos, José Araújo Dos Santos Júnior, Ana Maria Mendoça de Albuquerque Melo, Romilton Dos Santos Amaral, Rômulo Simões Cezar Menezes, Zahily Herrero Fernández, Lino Angel Valcárcel Rojas, Jairo Dias Bezerra, Alberto Antônio da Silva, Kennedy Francys Rodrigues Damascena, Nilson Vicente da Silva Medeiros
An increase of health problems has been reported in the city of Triunfo, Paraíba, NE Brazil. This pattern has been attributed to environmental radiation since there are uranium deposits in the neighboring municipalities. The present study aimed to carry a radiometric survey in Triunfo to determine effective dose from external outdoor radiation exposure. The results were obtained through 'in situ' measurements using a gamma spectrometry system. The results ranged from 0.06 to 0.38 mSv/y, mean of 0.20 mSv/y...
June 24, 2017: Radiation Protection Dosimetry
Masanao Kobayashi, Yasuki Asada, Kosuke Matsubara, Kazuyuki Minami, Shouichi Suzuki, Yuta Matsunaga, Tomonobu Haba, Ai Kawaguchi, Tomihiko Daioku, Hiroshi Toyama, Ryoichi Kato
Swallowing computed tomography (SCT) is a relatively new technique for the morphological and kinematic analyses of swallowing. However, no optimal scan protocols are available till date. We conducted the present SCT study to estimate the patient dose at various patient reclining positions. A RANDO phantom with a thermoluminescent dosemeter was placed on a hard Table board in a semi-reclining position at the centre and off-centre. According to predetermined scan protocols, irradiation was performed to acquire scanograms at reclining angles of 55° and 65°...
June 15, 2017: Radiation Protection Dosimetry
B Cijan, M Mukaj, F Bonutti, E Del Dò, M Floreani, D Kishta, E Martin, M Sponza, Al Mohannadi Salha Saad
Interventional radiology procedures have always been of particular concern because of the potential high dose to the workers. Special attention has recently been given to the lens dose: in 2011 the ICRP issued the recommendation 'Statement on Tissue Reactions' where a new limit of 20 mSv in a year, averaged over defined periods of 5 years, is given. Due to the impossibility of measuring the dose directly on the eye, there is not still a general consensus on a standardized methodology to assess the lens dose, which should be at the same time reliable, robust and simple to implement in practice...
June 8, 2017: Radiation Protection Dosimetry
Carlo Giordano, Ivo Monica, Rossana Gobbi, Lorenzo Barbattini
The aim of this study was to determine the dosimetric parameters of radiation to which orthopedic in-patients are exposed, using data drawn from the hospital's picture archiving and communication system. Data for 310 patients, relating to seven different anatomical districts, were examined. Femoral operations were divided into three types. The 75th percentile dose at the interventional reference point (IRP) exceeded 2 mGy only for femoral interventions (4.6-6.2 mGy) with 75th percentile kerma-area product (KAP) values ranging from 84...
June 8, 2017: Radiation Protection Dosimetry
Hamed Bagheri, Seyed Rabie Mahdavi, Babak Shekarchi, Farhad Manouchehri, Bagher Farhood
This research aimed to measure the received photon and thermal neutron doses to contralateral breast (CB) in breast cancer radiotherapy for various field sizes in presence of physical and dynamic wedges. The measurement of photon and thermal neutron doses was carried out on right breast region of RANDO phantom (as CB) for 18 MV photon beams. The dose measurements were performed by thermoluminescent dosimeter chips. These measurements obtained for various field sizes in presence of physical and dynamic wedges...
June 7, 2017: Radiation Protection Dosimetry
Jaeryong Yoo, Young-Woo Jin, Kwang Pyo Kim
Most internal radiation dose resulting from natural radionuclides is due to radon and radioactive potassium. Total body potassium (TBK) in human body may vary by ethnic group, gender and age. The objective of this study was to measure TBK and body potassium concentration in Korean subjects. Body potassium concentrations of the subjects were measured with a whole-body counter for 283 adult males and 181 adult females. Average TBK value and body potassium level were 111.2 g and 1.5 g kg-1 for males, while for females they were 71...
June 7, 2017: Radiation Protection Dosimetry
Ali B Alhailiy, Patrick C Brennan, Mark F McEntee, Peter L Kench, Elaine A Ryan
Cardiac computed tomography angiography (CCTA) is a commonly used diagnostic tool for cardiovascular disease. Despite constant improvements to imaging technologies, the radiation dose to patients from CCTA remains a concern when using this procedure. There remains a need for optimisation of CCTA procedures and accurate dose monitoring to reduce the potential risk of cancer. Establishing diagnostic reference levels (DRLs) allows for the assessment of radiation dose variations, enabling strategies aimed at standardising doses across radiological centres...
June 7, 2017: Radiation Protection Dosimetry
D Poudel, J A Klumpp, T L Waters, L Bertelli, R A Guilmette
The aim of this study is to present several approaches that have been used to model the behavior of radioactive materials (specifically Pu) in contaminated wounds. We also review some attempts by the health physics community to validate and revise the National Council on Radiation Protection and Measurements (NCRP) 156 biokinetic model for wounds, and present some general recommendations based on the review. Modeling of intake via the wound pathway is complicated because of a large array of wound characteristics (e...
June 7, 2017: Radiation Protection Dosimetry
M Kowatari, H Zutz, O Hupe
In high-energy photon reference fields the value of the air kerma rate is determined by using ionization chambers (ICs). From the charge collected inside the IC the dose can be calculated using a set of calibration and correction factors according to ISO 4037-2. A crucial parameter is the correction for the attenuation and scattering of the primary radiation due to the chamber wall. This parameter can be determined using Monte Carlo calculations. The evaluation of the factor was performed for a commercially available IC of the type Victoreen 550-3 under different build-up conditions...
June 7, 2017: Radiation Protection Dosimetry
Zhen Zhang, Changsong Hou, Dexing Lian, Zhongjian Ma, Junquan Tao, Weiguo Zhu
Some therapeutic proton synchrotron accelerators will be built for cancer treatment in China. The radiation produced by proton must be carefully evaluated and shielded for occupational disease hazard assessment and environmental impact assessment. Adopting the FLUKA code, a therapeutic room model, a synchrotron hall model and a high energy transport line tunnel model are constructed to get the ambient dose equivalent rate distributions. The ambient dose equivalent rates are also calculated with an empirical formula in some regions...
June 7, 2017: Radiation Protection Dosimetry
Hannele Niiniviita, Paulina Salminen, Juha M Grönroos, Irina Rinta-Kiikka, Saija Hurme, Timo Kiljunen, Jarmo Kulmala, Mika Teräs, Suvi Sippola, Johanna Virtanen number, NCT01022567.
June 7, 2017: Radiation Protection Dosimetry
Yoshiyuki Hosokai, Kenki Matsumoto, Masataka Kozakai, Kaito Takahashi, Akihito Usui, Thet Pe Win, Kenzo Muroi, Haruo Saito
No abstract text is available yet for this article.
August 1, 2017: Radiation Protection Dosimetry
Jeri L Anderson, A Iulian Apostoaei, James H Yiin, Chih-Yu Tseng
As part of an ongoing study of health effects in a pooled cohort of gaseous diffusion plant workers, organ dose from internal exposure to uranium was evaluated. Due to the introduction of recycled uranium into the plants, there was also potential for exposure to radiologically significant levels of 99Tc, 237Np and 238,239Pu. In the evaluation of dose response, these radionuclide exposures could confound the effect of internal uranium. Using urine bioassay data for study subjects reported in facility records, intakes and absorbed dose to bone surface, red bone marrow and kidneys were estimated as these organs were associated with a priori outcomes of interest...
August 1, 2017: Radiation Protection Dosimetry
William C Kovacs, Jianhua Yao, David A Bluemke, Les R Folio
Our current study was undertaken in order to compare CT exposures during various dose-reduction initiatives at the National Institutes of Health Clinical center, to show trends in exposure reduction over a 5-y period, and to provide benchmarks that other facilities may use. Using an in-house extraction tool (Radiation Exposure Extraction Engine), we derived CT exposure data from Digital Imaging and Communications in Medicine (DICOM) headers over 5 y. We present parameters used and compare most common exams between 2010 and 2015...
August 1, 2017: Radiation Protection Dosimetry
Mahua Karmakar, S Bhattacharyya, A Sarkar, P S Mazumdar, S D Singh
The suitability of the second derivative method for locating component peaks in complex thermoluminescence (TL) glow curves has been investigated in this work by considering both numerically simulated and experimental TL peaks. This technique is useful to acquire knowledge of the number of component peaks in a complex TL curve which in turn serves as a basic information before applying the deconvolution technique to the glow curve. To check the consistency of the results so obtained, we have also applied the first derivative technique to TL glow curves...
August 1, 2017: Radiation Protection Dosimetry
Hui Wang, Qianshu Chen, Guochao Liu, Youjia Tian, Fengmei Zhang, Jianying Qu, David Lim, Zhihui Feng
To assess the health statue of chronically exposed Chinese medical radiation workers. A cross-sectional study of 530 medical radiation workers in a city of China was conducted to document the health status and the monitored annually absorbed doses. Long-term and low-dose radiation exposure can affect a number of health indicators in the individuals, which covered the cardiovascular system, hematologic system, ophthalmology, liver and kidney's functions, chromosome aberration and micronucleus. The differences in the health status between male and female individuals were associated with job types and exposed years of service...
August 1, 2017: Radiation Protection Dosimetry
S M B Peters, D Zweers, F de Lange, J E M Mourik
This study aims to provide more insight in attenuation characteristics and corresponding lead (Pb) equivalences of a broad range of commercially available lead composite and nonlead protective garments. Thirty garments of five manufacturers (listed as 0.25-0.35-0.50 mm Pb equivalent) were tested. Transmission values were determined at 70, 90 and 110 kVp using an inverse broad beam geometry. Pb equivalence was determined using lead sheets as reference material. A substantial variability in photon transmission across garments was found...
August 1, 2017: Radiation Protection Dosimetry
Ranish Deedar Ali Khawaja, Sarabjeet Singh, Atul Padole, Alexi Otrakji, Diego Lira, Da Zhang, Bob Liu, Andrew Primak, George Xu, Mannudeep K Kalra
To determine the effect of patient off-centering on point organ radiation dose measurements in a human cadaver scanned with routine abdominal CT protocol. A human cadaver (88 years, body-mass-index 20 kg/m2) was scanned with routine abdominal CT protocol on 128-slice dual source MDCT (Definition Flash, Siemens). A total of 18 scans were performed using two scan protocols (a) 120 kV-200 mAs fixed-mA (CTDIvol 14 mGy) (b) 120 kV-125 ref mAs (7 mGy) with automatic exposure control (AEC, CareDose 4D) at three different positions (a) gantry isocenter, (b) upward off-centering and (c) downward off-centering...
August 1, 2017: Radiation Protection Dosimetry
Giovanni Mettivier, Matilde Costa, Nico Lanconelli, Anna Ianiro, Mariagabriella Pugliese, Maria Quarto, Paolo Russo
The aim of this study is to determine, via measurements on phantoms and Monte Carlo (MC) simulations, the dose distribution of absorbed dose in a cone-beam breast computed tomography scan. The absorbed dose volume distribution was measured inside a polyethylene cylindrical phantom, simulating adipose breast tissue, using LiF:Mg,Ti thermoluminescence dosimeters. A reasonable agreement (between 2 and 8%) between the simulated and measured data was observed. The 3D distribution of absorbed dose was evaluated at 40, 60 and 80 kV in a phantom simulating a pendant breast...
August 1, 2017: Radiation Protection Dosimetry
Kyle Copeland
Aircrew members can be exposed to higher annual doses of natural ionizing radiation than members of the general population in most parts of the world. The principal ionizing radiation to which they are exposed is galactic cosmic radiation (GCR). Among the particles present in the primary spectrum are heavy ions: relativistic nuclei of lithium and heavier elements. These ions have very high radiation weighting factors and can contribute significantly to the effective dose at altitudes above the Pfotzer maximum...
August 1, 2017: Radiation Protection Dosimetry
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