Journal of the ICRU最新文献

{"title":"Appendix В. Radiological Monitoring after the Accident at the Fukushima Daiichi Nuclear Power Station","authors":"","doi":"10.1093/jicru_ndy003","DOIUrl":"https://doi.org/10.1093/jicru_ndy003","url":null,"abstract":"The Tohoku District-off the Pacific Ocean Earthquake (magnitude 9.0) occurred near the northeast coast of Honshu in Japan at 14:46 on 11 March 2011 (Japan standard time, JST). The Fukushima Daiichi Nuclear Power Stations (NPS) of the Tokyo Electric Power Company (TEPCO) lost power to Units 1–4 because of the earthquake. Although the emergency diesel generators were activated, a tsunami caused by the earthquake flooded cooling seawater pumps, emergency diesel generators, and power panels. Without power for the cooling systems, water injection to each reactor pressure vessel could not be completed for Units 1–3 for a period of time, leading to fuel damage [Nuclear Emergency Response Headquarters Government of Japan (NERH), 2011a; 2011b; UNSCEAR, 2014]. Hydrogen explosions occurred in the reactor buildings of Unit 1 on 12 March and in Unit 3 on 14 March. An explosion was heard around the suppression chamber in the building of Unit 2 on 15 March. Hydrogen gas generated in Unit 3 flowed into Unit 4, and an explosion occurred there on 15 March. These serious phenomena led to the release of radioactive material (TEPCO, 2011; UNSCEAR, 2014). Figure B.1 shows the layout of the NPS. Radioactive material was released into the atmosphere and marine environment from Fukushima Daiichi NPS through dispersion and deposition (UNSCEAR, 2014). Principal releases to the atmosphere occurred on 12 March, 14–16 March, and 20–23 March, and the discharged radioactive material was deposited on the land. The Cabinet Office, Government of Japan (Cabinet) report to the IAEA summarizes the release of radioactive material assumed by the Nuclear and Industrial Safety Agency (I: 160 PBq; Cs: 15 PBq) and Nuclear Safety Commission of Japan (I: 150 PBq; Cs: 13 PBq) (NERH, 2011a). On 2 April 2011, highly contaminated water was observed near the water intake of Unit 2. The total amount of radioactive material discharged into seawater was estimated at approximately 4.7PBq by 6 April. From 4 to 10 April, low-level contaminated water was discharged into seawater to enable more contaminated water to be stored at the Fukushima Daiichi NPS. After the assessment for discharge in the early stage, numerous estimates of the source term and discharge were reported. UNSCEAR (2014) summarizes release estimates for the more significant radionuclides to the environment; the releases of I and Cs to the atmosphere were estimated as 100–500 and 6–20PBq, respectively. IAEA (2015) summarizes estimated atmospheric releases, finding the range of estimated releases are 90–700PBq for I and 7–50PBq for Cs.","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"72 1","pages":"144 - 162"},"PeriodicalIF":0.0,"publicationDate":"2015-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85956405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"2. Major Releases of Radionuclides to the Environment","authors":"","doi":"10.1093/jicru_ndy010","DOIUrl":"https://doi.org/10.1093/jicru_ndy010","url":null,"abstract":"A major release of radioactive material to the environment can potentially cause health effects and have psychological, social, and economic consequences. The type of health effects, their severity, and the length of time until effects appear are determined by the total dose received, type of radiations, rate and time pattern of exposure, organs or tissues exposed, health status and individual susceptibility of a person. The health effects, social and economic impacts, and distress for the affected populations can be considerably mitigated by adequate protective actions. Radiation monitoring provides vitally important information for emergency management, decision making, and protection of the public. The radioactive material released from a nuclear facility undergoes complex environmental transport processes, which cause the contamination of the air, terrestrial and aquatic environmental media, agricultural products, drinking water, consumer products, and ultimately external and internal exposure of people. Since it is important to understand how radiation affects people and the environment to effectively design a monitoring program to minimize and mitigate those effects, this Section explains source terms, radionuclides, pathways of exposure, and health effects. The discussion focuses on releases from light water reactors (LWR), the most popular type of modern nuclear power reactors. However, a substantial part of the content is also applicable to other emergencies involving large inventories of radioactive material.","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"47 1","pages":"36 - 4"},"PeriodicalIF":0.0,"publicationDate":"2015-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86717330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Appendix A. Radiological Monitoring after the Accident at the Chernobyl Nuclear Power Plant","authors":"","doi":"10.1093/jicru_ndy002","DOIUrl":"https://doi.org/10.1093/jicru_ndy002","url":null,"abstract":"The Chernobyl nuclear power plant accident was the most severe in the history of the nuclear industry. At 01:23 on 26 April 1986, Unit 4 of the Chernobyl nuclear power plant, located 130km to the northeast of Kyiv, the capital of Ukraine, was destroyed by two powerful explosions in the reactor core. The Chernobyl nuclear power plant was equipped with four Reaktor Bolszoj Moszcznosti Kanalnyj (RBMK) reactors, each with a graphite moderator, a thermal power of 3200MW and an electrical power of 1000MW. The explosions were caused by gross breaches of the operating procedures by staff and technical inadequacies in the safety systems (International Nuclear Safety Advisory Group, 1993). As a result of the explosions, highly radioactive core fragments were ejected onto the site and the roof of the building, the reactor closure head was lifted, and the core exposed to air. The air ignited the hot graphite, and it burned for 10 d. Radioactive substances in the form of gases, vapors, aerosols, and “hot particles” were ejected from the burning reactor. Wind currents under changing weather conditions spread the radioactive substances over Europe, principally Belarus, Ukraine, and Russia; the Chernobyl nuclear power plant is situated near the common border of those three countries. No more than 20 % of the radioactive discharge spread beyond Europe (De Cort et al., 1998; IAEA, 2006b). About six million people lived in areas of Belarus, Russia, and Ukraine that were contaminated with radionuclides from the Chernobyl accident (above 37 kBq/m of Cs). Among them, about 400 000 people lived in more contaminated areas, classified by Soviet authorities at the time as “areas of strict radiation control” (above 555 kBq/m of Cs). Of this group, 115 000 people were evacuated in the spring and summer of 1986 to non-contaminated areas. Another 220 000 people were relocated in subsequent years (IAEA, 2006b; UNSCEAR, 2011b). Environmental radiation monitoring was critical during the response. The data, analyzed in the context of national and international radiological standards, and assessments of the consequences of the accident informed authorities’ response to the accident, including public information on risks and the application of protective measures.","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"66 1","pages":"131 - 143"},"PeriodicalIF":0.0,"publicationDate":"2015-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85860954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prescribing, Recording, and Reporting of Stereotactic Treatments with Small Photon Beams","authors":"","doi":"10.1093/jicru/ndx013","DOIUrl":"https://doi.org/10.1093/jicru/ndx013","url":null,"abstract":"","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"14 2","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jicru/ndx013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68020513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"5. Image-Guided Beam Delivery","authors":"","doi":"10.1093/jicru_ndx007","DOIUrl":"https://doi.org/10.1093/jicru_ndx007","url":null,"abstract":"Daily setup variations and internal organ motion and deformation are a concern for external beam radiation therapy because they can modify the actual dose distribution in the patient, and consequently alter the clinical outcome and have effects on organs at risk different from the expectations of the planned dose distribution. To take these uncertainties into account, appropriate margins around the CTV are used to ensure adequate target coverage. This can result in a significant increase of the irradiated volume and, therefore, a significant additional exposure of healthy tissue. To reduce daily treatment variations, imageguided radiation therapy (IGRT) technology has been widely adopted to provide real-time geometric and anatomic information with the patient in the treatment position. The assumption behind the implementation of IGRT is that when the precision of radiation treatment is improved, it should increase survival and decrease complications. The concurrent clinical benefit of IGRT for the patient is the ability to monitor the changes in position and status of the tumor (i.e., shrinkage or expansion) and/or patient that can occur during the course of radiation treatment and to adjust the beam delivery accordingly.","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"30 1","pages":"77 - 92"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78389964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3. Definition of Volumes","authors":"","doi":"10.1093/jicru_ndx003","DOIUrl":"https://doi.org/10.1093/jicru_ndx003","url":null,"abstract":"Stereotactic radiotherapy delivers a very high dose to the target while relying heavily on tight margins and steep dose gradients to reduce the impact on organs at risk. Stereotactic radiosurgery has historically been used as a neurosurgery technique but in this context volumes have not strictly been defined. As introduced in ICRU Reports 50, 62, 71, 78, and 83 several volumes related to both tumor and normal tissues have been defined for use in the treatment planning and reporting processes (ICRU, 1993; 1999; 2004; 2007; 2010). It has been practice in (e.g., cranial radiosurgery) not to prescribe and, instead, to deliver spherical dose distributions. However, delineation of these volumes is a mandatory step in the planning process, as dose cannot be prescribed, recorded, and reported without specification of target volume and normal tissue at risk volume. In order to compare and reproduce clinical results, it is important that the definitions of the target and the organs at risk be as clear and as reproducible as possible. The volumes to be considered are:","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"337 1","pages":"55 - 63"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85335357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"1. Introduction","authors":"P. Wong, R. Campbell, O. Jacobsen, B. Fehr","doi":"10.1093/jicru_ndx008","DOIUrl":"https://doi.org/10.1093/jicru_ndx008","url":null,"abstract":"A small photon field is usually characterized by the following limitations to accurate dosimetry: (1) lack of lateral electron equilibrium; (2) obscuring of the primary photon source by the collimation system; and (3) the limitations of conventional broadfield detectors to accurately measure absorbed dose under small-field conditions. Small photon fields are used both for intensity-modulated radiation therapy (IMRT) (ICRU, 2010) and for stereotactic radiation therapy (SRT), which is discussed in the present report. Stereotaxy historically refers to the use of a 3dimensional (3D) coordinate system to localize intracranial targets. As of the time of publication of this report the concept of stereotactic treatment has been expanded to refer to the accurate and reproducible localization of the clinical target in space (i.e., at the mm level) and in time. SRT involves stereotactic localization techniques combined with delivery of multiple small photon fields in a few high-dose fractions, leading to a highly conformal dose delivery with steep dose gradients. Stereotactic localization techniques may include the use of relocatable rigid frames, image-guidance techniques, and other positioning tools. Stereotactic radiosurgery (SRS) is intracranial SRT delivered in a single fraction. Stereotactic body radiation therapy (SBRT) is the use of SRT for extracranial treatments. Other nomenclature such as SABR, which stands for stereotactic ablative (body) radiotherapy, is also used, but is not recommended by ICRU. In SRT techniques, a high dose per fraction is a prescribed absorbed dose to the target per treatment fraction. The dose is higher than what would be delivered using conventional radiation therapy in a similar situation. A “few fractions” refers to a number of fractions that is significantly lower than the number of fractions that would be delivered using conventional radiation therapy in the identical clinical situation (i.e., typically 25 fractions or more) in a non-palliative scenario. Fractionation protocols can range from a single fraction of over 180 Gy (Kooshkabadi et al., 2013) for functional indications to 12 fractions of 4.3 Gy (Ritter et al., 2009) in early prostate cancer. The therapeutic ratio is enhanced through delivery of highly conformal dose distributions with steep dose fall-off ensuring optimal dose in the target volume with minimal normal tissue irradiation. The scope of this report is to discuss spatially small photon beam delivery, including dosimetry, commissioning, and quality assurance as well as to recommend a framework for prescribing, recording, and reporting stereotactic radiotherapy. This report covers all pathologies eligible for stereotactic delivery (malignant and non-malignant). Note that other radiation therapy techniques may deliver a high dose per fraction in a well-defined target volume, such as, intra-operative radiation therapy or high dose rate brachytherapy (HDR-BT). These techniques are not discussed.","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"32 1","pages":"11 - 30"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78051883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"6. Quality Assurance","authors":"","doi":"10.1093/jicru/ndx011","DOIUrl":"https://doi.org/10.1093/jicru/ndx011","url":null,"abstract":"","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"14 2","pages":"93-99"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jicru/ndx011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68020516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Appendix A: Clinical Examples","authors":"","doi":"10.1093/jicru/ndx002","DOIUrl":"https://doi.org/10.1093/jicru/ndx002","url":null,"abstract":"","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"14 2","pages":"111-122"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jicru/ndx002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68020519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Executive Summary","authors":"","doi":"10.1093/jicru/ndx004","DOIUrl":"https://doi.org/10.1093/jicru/ndx004","url":null,"abstract":"","PeriodicalId":91344,"journal":{"name":"Journal of the ICRU","volume":"14 2","pages":"7-9"},"PeriodicalIF":0.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1093/jicru/ndx004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68020526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}