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Principles and Basic Concepts in Radiation Dosimetry
Published in W. P. M. Mayles, A. E. Nahum, J.-C. Rosenwald, Handbook of Radiotherapy Physics, 2021
As described in Chapter 3, charged particles (including those generated from uncharged-particle interactions – see Chapter 4) lose energy when they interact with matter. This energy is transferred to and absorbed by the irradiated medium. This energy absorption is the basis for the biological effects of radiotherapy that may ultimately result in tumour eradication (see Chapter 6). The absorption of (charged-particle kinetic) energy is expressed in terms of the fundamental quantity absorbed dose; this chapter is dedicated to radiation dosimetry, i.e. the determination (either experimentally or theoretically) of the absorbed dose in matter irradiated by ionising radiation.
Radiation Safety
Published in Debbie Peet, Emma Chung, Practical Medical Physics, 2021
Debbie Peet, Elizabeth Davies, Richard Raynor, Alimul Chowdhury
Radiation detectors are developing for personal dosimetry. Dynamic readout and artificial intelligence to look at the results of dosimetry measurements are active areas of research and development. Novel ways of training staff, involving other disciplines such as psychology, are beginning to develop.
Proton Therapy Dosimetry
Published in Arash Darafsheh, Radiation Therapy Dosimetry: A Practical Handbook, 2021
Michele M. Kim, Eric S. Diffenderfer
Radiation dosimetry encompasses the measurement techniques and procedures that allow quantification and verification of the radiation dose delivered during radiation therapy. These techniques are applied throughout the processes of accepting an accelerator system, commissioning a treatment planning system, performing daily, monthly, annual, and patient treatment plan specific quality assurance (QA). Many aspects of radiation dosimetry are equivalent between different radiation sources and delivery modalities; however, a few aspects are particular to particle therapy with protons.
Bio-acoustic signaling; exploring the potential of sound as a mediator of low-dose radiation and stress responses in the environment
Published in International Journal of Radiation Biology, 2022
Bruno F. E. Matarèse, Jigar Lad, Colin Seymour, Paul N. Schofield, Carmel Mothersill
We have reviewed the evidence for the emission of acoustic signals from irradiated biota of many different species, and conclude that all biological material has the potential to emit sound on interaction with ionizing radiation. There is not so far any evidence of sustained acoustic emission outside the time period of dose delivery, which would require either extremely inefficient relaxation processes or the triggering of an unknown energy-dependent cellular mechanism for producing sound. However, in situations of chronic exposure, such as external irradiation or internal contamination such as are found in contaminated ecosystems we would expect there to be sustained sound production if doses are sufficiently high. This is complicated by issues of intense local irradiation for example in internal contamination and raises problems already discussed about the meaning of environmental dosimetry (Beaugelin-Seiller et al. 2020). Transmission distances of such sound in air are likely to be short, given the acoustic modulus of air, its movement, and the presence of physical barriers to transmission such as interspersed objects in the environment. The physical characteristics of sound however suggest that transmission through the underlying matrix or at the interface of matrix and air, especially in wet environments, could be more efficient. Persuasive evidence exists that biota of all types, at the level of cells and organisms can respond to sound, and that in some cases to biophony. This strongly suggests that the ability to perceive and respond to the sounds emitted by biota under stress may be a widespread phenomenon.
Dosimetry and uncertainty approaches for the million person study of low-dose radiation health effects: overview of the recommendations in NCRP Report No. 178
Published in International Journal of Radiation Biology, 2022
Lawrence T. Dauer, André Bouville, Richard E. Toohey, John D. Boice, Harold L. Beck, Keith F. Eckerman, Derek Hagemeyer, Richard W. Leggett, Michael T. Mumma, Bruce Napier, Kathy H. Pryor, Marvin Rosenstein, David A. Schauer, Sami Sherbini, Daniel O. Stram, James L. Thompson, John E. Till, R. Craig Yoder, Cary Zeitlin
General guidance:The goal of the dosimetry is to estimate annual absorbed doses to the organ or tissue (annual organ dose) that is assumed to be the origin of the radiation-induced cancer of interest.When performing dose reconstructions for estimating annual organ doses, it is important to recognize that each sub-cohort may require a different methodology.Although each radiation sub-cohort is unique, common principles for dose assessment will facilitate the combination of sub-cohorts in the MPS.Where possible, annual organ doses obtained at other facilities where the individual may have worked are important to consider.Applying a decision level below which detailed dose reconstruction need not to be done is appropriate and can result in a considerable reduction in dosimetry effort without affecting the epidemiologic results.The coordination and close interaction of the dosimetric and epidemiologic teams is critical to the success of an epidemiologic study.
Using biodosimetry to enhance the public health response to a nuclear incident
Published in International Journal of Radiation Biology, 2021
L. K. Wathen, P. S. Eder, G. Horwith, R. L. Wallace
In contrast to physical dosimetry, which measures external or environmental exposure, radiation biodosimetry indicates the amount of absorbed radiation and reflects radiation-induced tissue/organ damage, which medical staff can use to more accurately assign individuals in need of increased levels of clinical evaluation, determine appropriate treatment options, or release them to evacuate the area. Because of the likelihood of scarce resources and high patient numbers, it is crucial that the available medications and staff efforts be directed to those individuals most able to benefit. In addition, biodosimetry test results could be used as early indicators of impending radiation-induced immunosuppression and resulting increased susceptibility to infection (Waselenko et al. 2004; Coleman and Koerner 2016; Dainiak 2018). This approach can complement the public health response by informing patient management, improving health and psychosocial outcomes, and saving far more lives (Coleman and Koerner 2016; Garty et al. 2017). However, there are currently no FDA cleared tests to measure absorbed radiation (Sullivan et al. 2013; Coleman and Koerner 2016).