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Ghosh A. Biological and cellular responses of humans to high-level natural radiation: A clarion call for a fresh perspective on the linear no-threshold paradigm. MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2022; 878:503478. [PMID: 35649671 DOI: 10.1016/j.mrgentox.2022.503478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/04/2022] [Accepted: 03/04/2022] [Indexed: 06/15/2023]
Abstract
There remains considerable uncertainty in obtaining risk estimates of adverse health outcomes of chronic low-dose radiation. In the absence of reliable direct data, extrapolation through the linear no-threshold (LNT) hypothesis forms the cardinal tenet of all risk assessments for low doses (≤ 100 mGy) and for the radiation protection principle of As Low As Reasonably Achievable (ALARA). However, as recent evidences demonstrate, LNT assumptions do not appropriately reflect the biology of the cell at the low-dose end of the dose-response curve. In this regard, human populations living in high-level natural radiation areas (HLNRA) of the world can provide valuable insights into the biological and cellular effects of chronic radiation to facilitate improved precision of the dose-response relationship at low doses. Here, data obtained over decades of epidemiological and radiobiological studies on HLNRA populations is summarized. These studies do not show any evidence of unfavourable health effects or adverse cellular effects that can be correlated with high-level natural radiation. Contrary to the assumptions of LNT, no excess cancer risks or untoward pregnancy outcomes have been found to be associated with cumulative radiation dose or in-utero exposures. Molecular biology-driven studies demonstrate that chronic low-dose activates several cellular defence mechanisms that help cells to sense, recover, survive, and adapt to radiation stress. These mechanisms include stress-response signaling, DNA repair, immune alterations and most importantly, the radiation-induced adaptive response. The HLNRA data is consistent with the new evolving paradigms of low-dose radiobiology and can help develop the theoretical framework of an alternate dose-response model. A rational integration of radiobiology with epidemiology data is imperative to reduce uncertainties in predicting the potential health risks of chronic low doses of radiation.
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Affiliation(s)
- Anu Ghosh
- Animal House Facility & Radiation Signaling Section, Radiation Biology & Health Sciences Division, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute (HBNI), Anushaktinagar, Mumbai 400 094, India.
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Wakeford R, Bithell JF. A review of the types of childhood cancer associated with a medical X-ray examination of the pregnant mother. Int J Radiat Biol 2021; 97:571-592. [PMID: 33787450 DOI: 10.1080/09553002.2021.1906463] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE For 65 years the interpretation of the statistical association between the risk of cancer in a child and a prior diagnostic X-ray examination of the abdomen of the pregnant mother has been debated. The objections to a direct cause-and-effect explanation of the association vary in their strength, but one of the most notable grounds for controversy is the finding from the first and largest case-control study reporting the association, the Oxford Survey of Childhood Cancers (OSCC), of an almost uniformly raised relative risk (RR) for nearly all of the types of cancer that are most frequent in children. Here we compare the antenatal X-ray associations found in the OSCC for different types of childhood cancer with the results of all other case-control and case-cohort studies appropriately combined in meta-analyses, and we also review the findings of the few cohort studies that have been conducted. CONCLUSIONS From the case-control/case-cohort studies other than the OSCC there are consistent and clear elevations of risk for all types of childhood cancer combined, all leukemia, and all cancers except leukemia combined. This compatibility of the findings of the OSCC with those of the combined other studies is less clear, or effectively absent, when some categories containing smaller numbers of incident cases/deaths are considered, but lack of precision of risk estimates due to sparse data presents inferential challenges, although there is a consistent absence of an association for bone tumors. Further, more recent studies almost certainly address lower intrauterine doses, with an anticipated decrease in estimated risks, which could be misleading when comparisons involve a limited number of studies that are mainly from later years, and a similar problem arises when having to employ all types of antenatal X-ray exposures for a study because data for abdominal exposures are absent. The problem of low statistical power is greater for cohort studies, and this, together with other shortcomings identified in the studies, limits the interpretational value of results. The findings of non-medical intrauterine exposure studies are constrained by sparse data and make a limited contribution to an understanding of the association. Certain aspects of the various studies require a need for caution in interpretation, but overall, the appropriate combination of all case-control/case-cohort studies other than the OSCC lends support to the inference that low-level exposure to radiation in utero proportionally increases the risk of the typical cancers of childhood to around the same level.
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Affiliation(s)
- Richard Wakeford
- Centre for Occupational and Environmental Health, The University of Manchester, Manchester, UK
| | - John F Bithell
- Department of Statistics, University of Oxford, Oxford, UK
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Boice J, Dauer LT, Kase KR, Mettler FA, Vetter RJ. Evolution of radiation protection for medical workers. Br J Radiol 2020; 93:20200282. [PMID: 32496817 PMCID: PMC7446021 DOI: 10.1259/bjr.20200282] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/11/2020] [Accepted: 05/15/2020] [Indexed: 11/05/2022] Open
Abstract
Within a few months of discovery, X-rays were being used worldwide for diagnosis and within a year or two for therapy. It became clear very quickly that while there were immense benefits, there were significant associated hazards, not only for the patients, but also for the operators of the equipment. Simple radiation protection measures were implemented within a decade or two and radiation protection for physicians and other operators has continued to evolve over the last century driven by cycles of widening uses, new technologies, realization of previously unidentified effects, development of recommendations and regulations, along with the rise of related societies and professional organizations. Today, the continue acceleration of medical radiation uses in diagnostic imaging and in therapeutic modalities not imagined at the turn of this century, such as positron emission tomography, calls for constant vigilance and flexibility to provide adequate protection for the growing numbers of medical radiation workers.
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Affiliation(s)
- John Boice
- National Council on Radiation Protection and Measurements, Bethesda, MD, USA
| | - Lawrence T Dauer
- Departments of Medical Physics and Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | | - Fred A Mettler
- Department of Radiology, University of New Mexico School of Medicine, Albuquerque,, NM, USA
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Vapiwala N, Thomas CR, Grover S, Yap ML, Mitin T, Shulman LN, Gospodarowicz MK, Longo J, Petereit DG, Ennis RD, Hayman JA, Rodin D, Buchsbaum JC, Vikram B, Abdel-Wahab M, Epstein AH, Okunieff P, Goldwein J, Kupelian P, Weidhaas JB, Tucker MA, Boice JD, Fuller CD, Thompson RF, Trister AD, Formenti SC, Barcellos-Hoff MH, Jones J, Dharmarajan KV, Zietman AL, Coleman CN. Enhancing Career Paths for Tomorrow's Radiation Oncologists. Int J Radiat Oncol Biol Phys 2019; 105:52-63. [PMID: 31128144 PMCID: PMC7084166 DOI: 10.1016/j.ijrobp.2019.05.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 05/03/2019] [Accepted: 05/08/2019] [Indexed: 02/07/2023]
Affiliation(s)
- Neha Vapiwala
- Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania.
| | - Charles R Thomas
- Department of Radiation Medicine, Oregon Health and Science University, Portland, Oregon
| | - Surbhi Grover
- Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania; University of Botswana, Gaborone, Botswana
| | - Mei Ling Yap
- Collaboration for Cancer Outcomes Research and Evaluation, Ingham Institute, University of New South Wales, Sydney, Australia; Liverpool and Macarthur Cancer Therapy Centre, Western Sydney University, Campbelltown, Australia; School of Public Health, University of Sydney, Camperdown, Australia
| | - Timur Mitin
- Department of Radiation Medicine Director, Program in Global Radiation Medicine, Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon
| | - Lawrence N Shulman
- Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mary K Gospodarowicz
- Department of Radiation Oncology, University of Toronto, Cancer Clinical Research Unit, Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - John Longo
- Department of Radiation Oncology Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Daniel G Petereit
- Department of Radiation Oncology, Rapid City Regional Cancer Care Institute, Rapid City, South Dakota
| | - Ronald D Ennis
- Clinical Network for Radiation Oncology, Rutgers and Cancer Institute of New Jersey, New Brunswick, New Jersey
| | - James A Hayman
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | - Danielle Rodin
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada; Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Jeffrey C Buchsbaum
- Radiation Research Program, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Bhadrasain Vikram
- Clinical Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - May Abdel-Wahab
- Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna, Austria
| | - Alan H Epstein
- Uniformed Service University of the Health Sciences, Bethesda, Maryland
| | - Paul Okunieff
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, Florida
| | - Joel Goldwein
- Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania; Elekta AB, Stockholm, Sweden
| | - Patrick Kupelian
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California; Varian Medical Systems, Palo Alto, California
| | - Joanne B Weidhaas
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California; MiraDx, Los Angeles, California
| | - Margaret A Tucker
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - John D Boice
- National Council on Radiation Protection and Measurements, Bethesda, Maryland; Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Clifton David Fuller
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Reid F Thompson
- Department of Radiation Medicine, Oregon Health and Science University, Portland, Oregon; VA Portland Health Care System, Portland, Oregon
| | - Andrew D Trister
- Department of Radiation Medicine, Oregon Health and Science University, Portland, Oregon
| | - Silvia C Formenti
- Department of Radiation Oncology, Weill Cornell Medicine, New York City, New York
| | | | - Joshua Jones
- Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Kavita V Dharmarajan
- Department of Radiation Oncology, Mount Sinai Hospital, Icahn School of Medicine at Mount Sinai, New York City, New York
| | - Anthony L Zietman
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts
| | - C Norman Coleman
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Boice JD, Held KD, Shore RE. Radiation epidemiology and health effects following low-level radiation exposure. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:S14-S27. [PMID: 31272090 DOI: 10.1088/1361-6498/ab2f3d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Radiation epidemiology is the study of human disease following radiation exposure to populations. Epidemiologic studies of radiation-exposed populations have been conducted for nearly 100 years, starting with the radium dial painters in the 1920s and most recently with large-scale studies of radiation workers. As radiation epidemiology has become increasingly sophisticated it is used for setting radiation protection standards as well as to guide the compensation programmes in place for nuclear weapons workers, nuclear weapons test participants, and other occupationally exposed workers in the United States and elsewhere. It is known with high assurance that radiation effects at levels above 100-150 mGy can be detected as evidenced in multiple population studies conducted around the world. The challenge for radiation epidemiology is evaluating the effects at low doses, below about 100 mGy of low-linear energy transfer radiation, and assessing the risks following low dose-rate exposures over years. The weakness of radiation epidemiology in directly studying low dose and low dose-rate exposures is that the signal, i.e. the excess numbers of cancers associated with low-level radiation exposure, is so very small that it cannot be seen against the very high background occurrence of cancer in the population, i.e. a lifetime risk of incidence reaching up to about 38% (i.e. 1 in 3 persons will develop a cancer in their lifetime). Thus, extrapolation models are used for the management of risk at low doses and low dose rates, but having adequate information from low dose and low dose-rate studies would be highly desirable. An overview of recently conducted radiation epidemiologic studies which evaluate risk following low-level radiation exposures is presented. Future improvements in risk assessment for radiation protection may come from increasingly informative epidemiologic studies, combined with mechanistic radiobiologic understanding of adverse outcome pathways, with both incorporated into biologically based models.
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Affiliation(s)
- J D Boice
- National Council on Radiation Protection and Measurements, Bethesda, Maryland, United States of America. Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
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Abstract
Radiation epidemiology has developed as a specialized field and has unique characteristics compared to the other fields of epidemiology. Radiation exposure assessment is highly quantified and health risk assessment can yield precise risks per unit dose in each organ. At the same time, radiation epidemiology also emphasizes the uncertainty of the estimated doses and risks. More radiation epidemiologists work in radiation societies rather than those of epidemiology. This specialization deepens the research of radiation studies but also results in fragmentation from general epidemiology. In addition to continued involvement with radiation-related sciences, therefore, more efforts to communicate with the other fields of epidemiology are necessary for radiation epidemiology.
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Affiliation(s)
- Won Jin Lee
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
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Newhauser WD, de Gonzalez AB, Schulte R, Lee C. A Review of Radiotherapy-Induced Late Effects Research after Advanced Technology Treatments. Front Oncol 2016; 6:13. [PMID: 26904500 PMCID: PMC4748041 DOI: 10.3389/fonc.2016.00013] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 01/12/2016] [Indexed: 01/01/2023] Open
Abstract
The number of incident cancers and long-term cancer survivors is expected to increase substantially for at least a decade. Advanced technology radiotherapies, e.g., using beams of protons and photons, offer dosimetric advantages that theoretically yield better outcomes. In general, evidence from controlled clinical trials and epidemiology studies are lacking. To conduct these studies, new research methods and infrastructure will be needed. In the paper, we review several key research methods of relevance to late effects after advanced technology proton-beam and photon-beam radiotherapies. In particular, we focus on the determination of exposures to therapeutic and stray radiation and related uncertainties, with discussion of recent advances in exposure calculation methods, uncertainties, in silico studies, computing infrastructure, electronic medical records, and risk visualization. We identify six key areas of methodology and infrastructure that will be needed to conduct future outcome studies of radiation late effects.
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Affiliation(s)
- Wayne D. Newhauser
- Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
- Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, LA, USA
| | | | - Reinhard Schulte
- Department of Basic Sciences, Loma Linda University Medical Center, Loma Linda, CA, USA
| | - Choonsik Lee
- Radiation Epidemiology Branch, National Institutes of Health, Rockville, MD, USA
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9
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Preston RJ, Boice JD, Brill AB, Chakraborty R, Conolly R, Hoffman FO, Hornung RW, Kocher DC, Land CE, Shore RE, Woloschak GE. Uncertainties in estimating health risks associated with exposure to ionising radiation. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2013; 33:573-588. [PMID: 23803503 DOI: 10.1088/0952-4746/33/3/573] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The information for the present discussion on the uncertainties associated with estimation of radiation risks and probability of disease causation was assembled for the recently published NCRP Report No. 171 on this topic. This memorandum provides a timely overview of the topic, given that quantitative uncertainty analysis is the state of the art in health risk assessment and given its potential importance to developments in radiation protection. Over the past decade the increasing volume of epidemiology data and the supporting radiobiology findings have aided in the reduction of uncertainty in the risk estimates derived. However, it is equally apparent that there remain significant uncertainties related to dose assessment, low dose and low dose-rate extrapolation approaches (e.g. the selection of an appropriate dose and dose-rate effectiveness factor), the biological effectiveness where considerations of the health effects of high-LET and lower-energy low-LET radiations are required and the transfer of risks from a population for which health effects data are available to one for which such data are not available. The impact of radiation on human health has focused in recent years on cancer, although there has been a decided increase in the data for noncancer effects together with more reliable estimates of the risk following radiation exposure, even at relatively low doses (notably for cataracts and cardiovascular disease). New approaches for the estimation of hereditary risk have been developed with the use of human data whenever feasible, although the current estimates of heritable radiation effects still are based on mouse data because of an absence of effects in human studies. Uncertainties associated with estimation of these different types of health effects are discussed in a qualitative and semi-quantitative manner as appropriate. The way forward would seem to require additional epidemiological studies, especially studies of low dose and low dose-rate occupational and perhaps environmental exposures and for exposures to x rays and high-LET radiations used in medicine. The development of models for more reliably combining the epidemiology data with experimental laboratory animal and cellular data can enhance the overall risk assessment approach by providing biologically refined data to strengthen the estimation of effects at low doses as opposed to the sole use of mathematical models of epidemiological data that are primarily driven by medium/high doses. NASA's approach to radiation protection for astronauts, although a unique occupational group, indicates the possible applicability of estimates of risk and their uncertainty in a broader context for developing recommendations on: (1) dose limits for occupational exposure and exposure of members of the public; (2) criteria to limit exposures of workers and members of the public to radon and its short-lived decay products; and (3) the dosimetric quantity (effective dose) used in radiation protection.
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Affiliation(s)
- R Julian Preston
- National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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Apigenin ameliorates gamma radiation-induced cytogenetic alterations in cultured human blood lymphocytes. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2012; 747:71-76. [DOI: 10.1016/j.mrgentox.2012.04.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 03/13/2012] [Accepted: 04/02/2012] [Indexed: 11/23/2022]
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Boice JD. Radiation epidemiology: a perspective on Fukushima. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2012; 32:N33-N40. [PMID: 22395193 DOI: 10.1088/0952-4746/32/1/n33] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
For nearly 100 years, epidemiologic studies of human populations exposed to ionising radiation have provided quantitative information on health risks. High dose deterministic (tissue reaction) effects result when sufficient numbers of functioning cells are killed, such as in bone marrow depression that can lead to death. Lower dose stochastic effects are probabilistic in nature and include an increased risk of cancer later in life and heritable genetic defects, although genetic conditions in the children of irradiated parents have yet to be convincingly demonstrated. Radiation studies are of diverse populations and include not only the Japanese atomic bomb survivors, but also patients treated with radiation for malignant and non-malignant disease; patients exposed for diagnostic purposes; persons with intakes of radionuclides; workers occupationally exposed; and communities exposed to environmental and accidentally released sources of radiation. Much is known about radiation and its risks. The major unanswered question in radiation epidemiology, however, is not whether radiation causes cancer, but what the level of risk is following low dose (<100 mSv) or low dose rate exposures. Paracelsus is credited with first articulating that the 'poison is in the dose', which for radiation epidemiology translates as 'the lower the dose, the lower the risk' and, an important corollary, the lower the dose, the greater the difficulty in detecting any increase in the number of cancers possibly attributable to radiation. In contrast to the Chernobyl reactor accident, the Fukushima reactor accident has to date resulted in no deterministic effects and no worker deaths. Estimates to date of population doses suggest very low uptakes of radioactive iodine which was a major determinant of the epidemic of thyroid cancer following childhood exposures around Chernobyl. The estimates to date of population doses are also much lower (and the distribution much narrower) than the doses for which cancer excesses have been detected among atomic bomb survivors after 60 years of follow-up. Studies of populations exposed to low doses are also limited in their ability to account for important lifestyle factors, such as cigarette smoking and medical x-ray exposures, which could distort findings. Studies of the Fukushima population should be and are being considered for reassurance and health care reasons. Apart from as regards the extreme psychological stress caused by the horrific loss of life following the tsunami and the large-scale evacuation from homes and villages, such studies have limited to no chance of providing information on possible health risks following low dose exposures received gradually over time--the estimated doses (to date) are just too small.
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Affiliation(s)
- John D Boice
- Department of Medicine, Division of Epidemiology, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN, USA.
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Guillerman RP. Newer CT applications and their alternatives: what is appropriate in children? Pediatr Radiol 2011; 41 Suppl 2:534-48. [PMID: 21847736 DOI: 10.1007/s00247-011-2163-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 05/18/2011] [Accepted: 05/25/2011] [Indexed: 12/20/2022]
Abstract
Innovations in image acquisition and reconstruction technologies have greatly expanded the range of CT applications available in the routine clinical setting. CT images of sub-millimeter resolution can now be acquired of entire body regions in a few seconds or even sub-second time, allowing depiction of fine anatomical detail uncompromised by motion artifact. With sophisticated visualization software, image data can be processed into multiplanar, volume-rendered, cine and other formats to better display anatomical abnormalities and facilitate newer applications such as CT angiography, enterography, urography, tracheobronchography and cardiac CT. Newer applications including dual-energy material decomposition CT are furthering the transition of CT from a purely morphological to a combined anatomical, functional and metabolic imaging technique. These newer applications have largely been pioneered in adult populations, and heightened concern of the risk of carcinogenesis from ionizing radiation tempers dissemination of their use in children. Similar information can often be gleaned from alternative imaging modalities without ionizing radiation exposure, such as MRI and US, and what is most appropriate in children will depend on relative diagnostic efficacy, cost, availability and local expertise.
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Affiliation(s)
- R Paul Guillerman
- Department of Pediatric Radiology, Baylor College of Medicine, Texas Children's Hospital, 6701 Fannin St., Suite 470, Houston, TX 77030, USA.
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Boice JD, Cohen SS, Mumma MT, Ellis ED, Eckerman KF, Leggett RW, Boecker BB, Brill AB, Henderson BE. Updated Mortality Analysis of Radiation Workers at Rocketdyne (Atomics International), 1948–2008. Radiat Res 2011; 176:244-58. [DOI: 10.1667/rr2487.1] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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