Current global and Korean issues in radiation safety of nuclear medicine procedures

Abstract

In recent years, the management of patient doses in medical imaging has evolved as concern about radiation exposure has increased. Efforts and techniques to reduce radiation doses are focussed not only on the basis of patient safety, but also on the fundamentals of justification and optimisation in cooperation with international organisations such as the International Commission on Radiological Protection, the International Atomic Energy Agency, and the World Health Organization. The Image Gently campaign in children and Image Wisely campaign in adults to lower radiation doses have been initiated in the USA. The European Association of Nuclear Medicine paediatric dosage card, North American consensus guidelines, and Nuclear Medicine Global Initiative have recommended the activities of radiopharmaceuticals that should be administered in children. Diagnostic reference levels (DRLs), developed predominantly in Europe, may be an important tool to manage patient doses. In Korea, overexposure to radiation, even from the use of medical imaging, has become a public issue, particularly since the accident at the Fukushima nuclear power plant. As a result, the Korean Nuclear Safety and Security Commission revised the technical standards for radiation safety management in medical fields. In parallel, DRLs for nuclear medicine procedures have been collected on a nationwide scale. Notice of total effective dose from positron emission tomography-computed tomography for cancer screening has been mandatory since mid-November 2014.

1. INTRODUCTION

Medical radiation exposure is almost always voluntary and is generally accepted to have more benefits than risks. As such, the use of medical imaging procedures continues to increase. The use of radiation for medical exposure of patients accounts for >95% of man-made radiation exposure, and is only exceeded worldwide by natural background radiation as a source of exposure (UNSCEAR, 2000). In a preliminary analysis for 2006 in the USA, the contribution of medical radiation exposure of patients was considered to be similar in magnitude to natural background radiation as a source of exposure of the population. Compared with 1982 and 2006, the per-capita dose has increased almost six-fold (from 0.54 to approximately 3.0 mSv), and the collective dose has increased more than seven-fold (from 124,000 to approximately 900,000 man-Sv). The largest contributions and exposure increases have come primarily from computed tomography (CT) scanning and nuclear medicine (Mettler et al., 2008).

Radiation detriments, including the results of a recent article on cancer risks related to low-dose ionising radiation from medical imaging (Eisenberg et al., 2011) and the incidence of CT radiation overexposure to patients, have increased fear of overexposure to radiation from CT scans (Zarembo, 2009). In Korea, overexposure to radiation, even from medical imaging, has become a public issue, particularly since the accident at the Fukushima nuclear power plant in Japan. Issues on reducing radiation exposure during medical procedures continue to raise concerns about radiation risk among the general public and scientific community.

Fortunately, large-scale campaigns such as Image Gently (http://www.imagegently.org), Image Wisely (http://www.imagewisely.org/), and Choosing Wisely (http://www.choosingwisely.org/) advocate the reduction of ionising imaging exposure in children, unnecessary imaging in adults, and avoidance of inappropriate imaging procedures. In addition, efforts have been made to optimise dose and improve technology in cooperation with international organisations such as the International Commission on Radiological Protection (ICRP), the International Atomic Energy Agency (IAEA), and the World Health Organization (WHO) to reduce the exposure of patients to ionising radiation during medical imaging procedures. The purpose of this paper is to review current global and Korean issues in radiation safety of nuclear medicine procedures, with emphasis on radiation exposure from nuclear medicine examinations.

2. MEDICAL RADIATION EXPOSURE FROM NUCLEAR MEDICINE PROCEDURES

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 2008 Report (UNSCEAR, 2008) estimated that 32.7 million global diagnostic nuclear medicine examinations are performed annually, which represents an increase of 0.2 million examinations year⁻¹ or <1% since the 1991–1996 survey. The 24% of the global population living in healthcare level I countries receive approximately 90% of all nuclear medicine examinations. The annual frequency of diagnostic nuclear medicine examinations per 1000 population in healthcare level I countries has increased from 11 in 1970–1979 to 19 in 2008. Comparative values for healthcare level II countries also exhibit an increase, from 0.9 per 1000 to 1.1 per 1000 in 1997–2007. Over the same period, the annual collective effective dose to the world’s population due to diagnostic nuclear medicine examinations rose from 150,000 to 202,000 man-Sv, representing an increase of 52,000 man-Sv or approximately 35%. Nuclear medicine represents approximately 6% of the collective dose from the diagnostic use of radiation. The increase in the global collective effective dose from diagnostic nuclear medicine examinations results from two factors. Firstly, the average effective dose per procedure has increased from 4.6 mSv (UNSCEAR, 2000) to the present estimate of 6.0 mSv, an increase of nearly one-third in the average effective dose per procedure. Secondly, there has been an increase in the annual number of diagnostic nuclear medicine examinations performed among the world’s population.

The National Council on Radiation Protection and Measurements (NCRP) Report 160 (Bolus, 2013) stated that the average exposure of the general US population to ionising radiation increased from 3.6 mSv in the 1980s to 6.2 mSv in 2006. In the 1980s, medical procedures accounted for 15% of all exposures, whereas they accounted for 48% in 2006. The increase was led primarily by increased use of CT imaging, followed by nuclear cardiology procedures. When comparing data from 1972 and 2006, the report revealed that there were 15.7 nuclear medicine examinations or visits per 1000 people in 1972, compared with 60.3 million in 2006, representing an increase of approximately 284%. The annual number of nuclear medicine procedures over that time increased from approximately 3.3 million to 18.1 million, or approximately 448%. As far as effective dose estimates for nuclear medicine procedures are concerned, NCRP Report 160 indicated that nuclear cardiology perfusion Tc-99 m sestamibi/Tl-201 studies resulted in an effective dose per procedure of 17.7 mSv. The total collective effective dose for all nuclear medicine procedures in 2005 (the year analysed by the NCRP Report 160 Committee) was approximately 220,500 man-Sv. Nuclear cardiology procedures accounted for 85.2% of this total [187,915 man-Sv for cardiac procedures (187,915/220,500 man-Sv ×100% = 85.2%)]. Bone scans came in second at 9.3%. In another study, the proportion of overall effective dose from nuclear medicine imaging procedures was found to be approximately one-quarter (24.8%) of that of procedures making the largest contributions to radiation exposure in the study population (Fazel et al., 2009). Myocardial perfusion imaging alone accounted for over 22% of the total effective dose, while CT scans of the abdomen, pelvis, and chest accounted for approximately 38%. Bone scans accounted for 1.4%, thyroid uptake scans accounted for 0.7%, and cardiac resting ventriculography accounted for 0.6%.

In 2007, the average effective dose to the Korean population was 3.7 mSv year⁻¹. Dominant contributions (80.3%) were from natural sources. Almost all of the remaining dose (19.7%) was due to medical exposure (KINS, 2007). The annual collective dose was 27,440 man-Sv [diagnostic radiology: 22,880 man-Sv (83.4%); nuclear medicine: 4560 man-Sv], which can be reduced to the annual per-capita effective dose of 0.58 mSv by dividing by the Korean population of 47.7 million. In 2002, the collective effective dose from nuclear medicine was 4560 man-Sv, and the per-capita dose was 0.096 mSv. In terms of the contribution of nuclear medicine to the collective dose, myocardial single photon emission CT scans accounted for 2600 man-Sv (58.6%), bone scans accounted for 1060 man-Sv (23.8%), and thyroid scans accounted for 274 man-Sv (6.1%) (Kwon et al., 2005).

In 2013, according to national statistical data for diagnostic radiation exposure in Korea collected from four public institutes and government agencies between 2006 and 2013, the annual frequency of diagnostic medical examinations was 231 million, demonstrating rapid growth of 54.4% compared with 150 million in 2006 (Lee et al., 2015). The average collective effective dose and per-capita effective dose in 2013 were 78,730 man-Sv and 1.54 mSv, respectively, which are 81.5% and 73.9% increases over those in 2006, respectively. The frequencies of CT and nuclear medicine examinations increased significantly by 120.7% and 90.4%, respectively, and the annual per-capita effective doses were increased significantly by 118.8% and 103%, respectively, in 2013. In terms of the distribution of annual frequency of all types, positron emission tomography (PET)-CT had the highest average annual increase in rate (49.4%); frequency of PET-CT increased by 815.2% between 2006 and 2013 in accordance with the increased PET-CT penetration rate of 228.6% over the same period. Reimbursement seems to be one of the most important factors affecting the increased frequency of PET-CT. Korea began reimbursement by public insurance systems in June 2006, at a cost of approximately 710,000 KRW (US$ 764) (Kim et al., 2012). The Korean population is ageing rapidly with the progress of medical technology, and use of examinations demanding high radiation exposure, such as CT and nuclear medicine examinations, has increased rapidly.

3. IMPLEMENTATION OF THE NEW INTERNATIONAL STANDARDS FOR RADIOLOGICAL PROTECTION

The international standards for radiological protection were developed from widely accepted radiological protection and safety principles, such as those published in ICRP reports and IAEA safety series. ICRP revised the fundamental recommendations about protection against ionising radiation in 2007 (ICRP, 2007a). Subsequently, IAEA revised its International European Basic Safety Standards (BSS) to take into account the changes in the ICRP 2007 Recommendations. ‘General Safety Requirements Part 3 – Radiological Protection and Safety of Radiation Sources: International Basic Safety Standards’ was approved by the IAEA Board of Governors at its meeting in 2011, and was issued as General Safety Requirements Part 3 in 2014 (IAEA, 2014).

The recently published Council Directive 2013/59/European Atomic Energy Community (Euratom) (new BSS) was adopted on 5 December 2013. The new European BSS incorporate the ICRP 2007 Recommendations, and harmonise the European Union (EU) regime with the BSS of IAEA. The new European BSS repeal previous European legislation on which the national systems for radiological protection in medicine of the 28 EU Member States are based, including the 96/29/Euratom BSS and the 97/43/Euratom Medical Exposure Directives. While most of the elements of the previous legislation have been kept, there are several legal changes that will have important effects on regulation and practice in the field all over Europe. These include, among others: (1) strengthening implementation of the justification principle and expanding it to medically exposed asymptomatic individuals; (2) more attention to interventional radiology; (3) new requirements for dose recording and reporting; (4) increased role of the medical physics expert in imaging; (5) new set of requirements for preventing and following up on accidents; and (6) new set of requirements for procedures where radiological equipment is used for people for non-medical purposes (non-medical imaging exposure). The EU Member States have to enforce the new EU BSS before January 2018 and bring into force the laws, regulations, and administrative provisions necessary to comply. The European Commission has certain legal obligations and powers to verify the compliance of national measures with the EU laws and, wherever necessary, issue recommendations to, or open infringement cases against, national governments (Simeonov, 2015).

As soon as the revision of the BSS was completed, the Korean Government implemented the changes in the BSS and ICRP 2007 Recommendations into its national radiological protection laws and regulations (Cho and Kim, 2009). The Korean Nuclear Safety and Security Commission (NSSC) revised ‘Regulations on Technical Standards for Radiation Safety Control, etc’. in mid-December 2013 (NSSC, 2014). Section 3, entitled ‘Medical safety control in these new regulations’, has been changed completely, as follows: (1) defining medical exposure as exposure of patients resulting from their treatment and diagnosis, and of biomedical research volunteers and carers and comforters, and of the embryo or fetus and infant being breast fed; (2) implementation of the justification principle and optimisation of protection and safety; (3) preventing and following up on unintended and accidental medical exposures; (4) safety control of patients released after radionuclide therapy; and (5) radiological protection for pregnant or breast-feeding female patients. The Korean NSSC decided to revise ‘Technical Standards for Radiation Safety Management in Medical Fields’ in accordance with the revised regulations (NSSC, 2015). This notice was issued by the Korean Government in the first quarter of 2015.

4. JUSTIFICATION

ICRP recommendations for radiological protection and safety in medicine are given in Publication 105 (ICRP, 2007b), which explains that the principle of justification applies at three levels in medicine, as described below. At the first level, the proper use of radiation in medicine is accepted as doing more good than harm to society. At the second level, a specified procedure is justified for a group of patients showing relevant symptoms, or for a group of individuals at risk for a clinical condition that can be detected and treated. At the third level, the application of a specified procedure to an individual patient is justified if that particular application is judged to do more good than harm to the individual patient. Hence, all individual medical exposures should be justified in advance, taking into account the specific objectives of the exposure and the characteristics of the individual involved. In the International BSS for protection against ionising radiation and for the safety of radiation sources (IAEA, 2014), medical exposures should be justified by weighing the diagnostic or therapeutic benefits that they are expected to yield against the radiation detriment that they might cause, with account taken of the benefits and risks of available alternative techniques that do not involve medical exposure. The justification of medical exposure for an individual patient should be carried out by means of consultation between the radiological medical practitioner and the referring medical practitioner, as appropriate, with account taken, particularly for patients who are pregnant, breast feeding, or paediatric, of: (1) the appropriateness of the request; (2) the urgency of the radiological procedure; (3) the characteristics of the medical exposure; (4) the characteristics of the individual patient; and (5) relevant information from the patient’s previous radiological procedures.

Relevant national or international referral guidelines should be taken into account for justification of the medical exposure of an individual patient in a radiological procedure. Imaging referral guidelines provide physicians with information regarding procedures that are most likely to yield the most informative results, and whether another modality is equally or more effective, and therefore more appropriate. Examples of referral guidelines include the American College of Radiology (ACR) Appropriateness Criteria (ACR, 2014) and ‘iRefer: Making the Best Use of Clinical Radiology’ (RCR, 2012).

A number of international, regional, and national initiatives are being conducted to increase appropriateness, reduce unnecessary radiation exposures, and thus prevent unnecessary radiation risks. Activities enhancing implementation of justification include the Working Party on Justification of Medical Imaging composed of members of ICRP Committee 3 and external experts (ICRP, 2014), Global Initiative on Radiation Safety in Health Care Settings of WHO (WHO, 2008), the framework of the IAEA International Action Plan for Radiological Protection of Patients (IAEA, 2002), large-scale campaigns pursued intensively by professional societies such as Image Gently and Eurosafe (http://www.eurosafeimaging.org), and numerous national initiatives on this topic (Perez, 2015).

In the International BSS, justification for radiological procedures to be performed as part of a health screening programme for asymptomatic populations should be carried out by the health authority in conjunction with appropriate professional bodies. The individual should be informed of the expected benefits, risks, and limitations of the procedure. In Korea, the standard notice for individuals and recommendations for medical institutions regarding the use of PET-CT for voluntary cancer screening of asymptomatic individuals was made and released by the Korean Medical Association in collaboration with the Ministry of Health and Welfare, the Korean Society of Nuclear Medicine (KSNM), the Korean Hospital Association, and the Korean Consumer Agency in 2014. Therefore, there has been a requirement to notify patients of the total effective radiation dose received from F-18 fluorodeoxyglucose PET-CT for cancer screening, with average annual natural radiation dose (3 mSv), since mid-November 2014 in Korea.

5. OPTIMISATION

The basic aim of the optimisation of protection is to adjust the protection measures for a source of radiation in such a way that the net benefit is maximised. In the case of exposure from diagnostic and interventional medical procedures, the objective of diagnostic reference levels (DRLs) is the optimisation of protection. The concept of DRLs was introduced in Publication 60 (ICRP, 1990) as a form of investigation level used to identify situations where optimisation of protection may be required in the medical exposure of patients, and the use of DRLs was recommended in Publication 73 (ICRP, 1996) with further information in Supporting Guidance 2 (ICRP, 2001). Publications 103 and 105 (ICRP, 2007a,b) summarised previous definitions and recommendations about DRLs. The objective of DRLs is to help avoid radiation dose to the patient that does not contribute to the clinical purpose of a medical imaging task.

The International BSS (IAEA, 2014) state that registrants, licensees, and radiological medical practitioners should ensure that protection and safety are optimised for each medical exposure. For diagnostic radiological procedures and image-guided interventional procedures, the radiological medical practitioner, in cooperation with the medical radiation technologist and the medical physicist, and, if appropriate, the radiopharmacist or radiochemist, should ensure that the following are used: (1) appropriate medical radiological equipment and software, and, for nuclear medicine, appropriate radiopharmaceuticals; and (2) appropriate techniques and parameters to deliver medical exposure of the patient that is the minimum necessary to fulfil the clinical purpose of the radiological procedure, taking into account relevant norms of acceptable image quality established by relevant professional bodies, and relevant DRLs established in accordance with paragraphs 3.148 and 3.169 in the standards. The particular aspects of medical exposures are considered in the optimisation process for paediatric patients subject to medical exposure.

As described above, a number of international, regional, and national initiatives are also being conducted to optimise radiation exposures in medical imaging procedures. Activities enhancing implementation of optimisation include the Working Party on DRL Optimisation of Medical Imaging composed of members of ICRP Committee 3 (ICRP, 2014); the WHO Global Initiative on Radiation Safety in Health Care Settings (WHO, 2008); the framework of the IAEA International Action Plan for Radiological Protection of Patients (IAEA, 2002); the Bonn Call for Action (IAEA, 2012); multi-society campaigns pursued by professional societies such as Image Gently, Image Wisely, and Choosing Wisely; and several initiatives on paediatric radiopharmaceutical administered doses (Fahey et al., 2015).

In Korea, DRLs for nuclear medicine procedures were adopted from data of patient activities administered for each diagnostic nuclear imaging examination, collected using the web-based online database of KSNM (http://www.ksnm.or.kr/stats/) in 2014. In the first nationwide survey, DRLs were established for 41 examinations of diagnostic nuclear medicine procedures in 155 hospitals by KSNM and the Medical Radiation Safety Research Center (http://www.mrsrc.kr) designated by the Korean NSSC.

6. INTERNATIONAL ACTIVITIES ON RADIOLOGICAL PROTECTION OF PATIENTS

6.1. ICRP

ICRP (1996) published Publication 73, entitled ‘Radiological protection and safety in medicine’, to expand on the application in medicine of the Commission’s 1990 Recommendations (ICRP, 1990). Publication 105, entitled ‘Radiological protection in medicine’ (ICRP, 2007b), was published in 2008 to augment Publication 73 and underpin the Commission’s 2007 Recommendations (ICRP, 2007a) with regard to the medical exposure of patients, including their comforters and carers, and volunteers in biomedical research. ICRP continues to work on radiological protection in medicine. Current work topics in progress include: occupational radiological protection in brachytherapy; justification in medical uses of ionising radiation including imaging of asymptomatic individuals; radiological protection in therapy with radiopharmaceuticals; occupational protection issues in interventional procedures (fluoroscopically guided); and DRLs for diagnostic and interventional imaging. At the time of writing (September 2015), the draft on ‘DRLs in medical imaging’ by Committee 3 is in progress (Vañó et al., 2015).

6.2. IAEA

6.2.1. International Action Plan for the Radiological Protection of Patients

In 2002, IAEA launched the International Action Plan for the Radiological Protection of Patients (IAEA, 2002). The fourth meeting of the Steering Panel was held in 2010, and the plan was met with remarkable success. Some of the main items and recommendations included in the summary report of that meeting were: (1) authenticated information to IAEA for inclusion on the Radiological Protection of Patients (RPOP) website; (2) promotion of educational reporting systems (on radiation incidents); (3) introduction of radiological protection into medical and paramedical curricula; (4) urgent international agreement on staffing needs in radiation medicine; (5) improvement in the availability of dose data in digital imaging; (6) including patient dose data in the clinical history of patients; (7) appropriate follow-up and lessons learned from incidents and accidents in radiation medicine; and (8) promotion of the use of evidence-based referral guidelines.

6.2.2. Radiological Protection of Patients website

The RPOP website (https://rpop.iaea.org) has been a significant instrument of IAEA to communicate information to help health professionals achieve safer use of radiation in medicine for the benefit of patients, along with information to patients and the public on the benefits and risks of ionising radiation in medical applications. This website was launched in September 2006 and has grown to be the main website worldwide in the area of medical radiological protection (Rehani, 2013). The website provides extensive material on radiological protection in the use of radiology, nuclear medicine, radiotherapy, interventional fluoroscopy, interventional cardiology, other specialities, and imaging modalities including PET-CT scanning. Radiological protection of patients in nuclear medicine, covering diagnostic nuclear medicine, therapeutic nuclear medicine, and biomedical research, is included on the RPOP website. This website also contains training materials on radiological protection in nuclear medicine and radiological protection in PET-CT. Pregnant women form a specific group for radiological protection purposes, and they are dealt with separately.

6.2.3. Bonn Call for Action

IAEA held the International Conference on Radiological Protection in Medicine: Setting the Scene for the Next Decade in Bonn, Germany in December 2012, with the specific purpose of identifying and addressing issues arising in radiological protection in medicine. The conference was co-sponsored by WHO, hosted by the Government of Germany through the Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety, and attended by 536 participants and observers from 77 countries and 16 organisations. An important outcome of the conference was the identification of responsibilities and a proposal for priorities for stakeholders regarding radiological protection in medicine for the next decade. This specific outcome is known as the ‘Bonn Call for Action’ (IAEA, 2012). The aims of the Bonn Call for Action are to: (1) strengthen the radiological protection of patients and health workers overall; (2) attain the highest benefit with the least possible risk to all patients by the safe and appropriate use of ionising radiation in medicine; (3) aid the full integration of radiological protection into healthcare systems; (4) help improve the benefit–risk dialogue with patients and the public; and (5) enhance the safety and quality of radiological procedures in medicine. In March 2015, the US Food and Drug Administration released an update on its efforts in response to the Bonn Call for Action, with a list of 10 priorities for radiological protection (FDA, 2015). The 10 calls for action were: (1) enhance implementation of the principle of justification; (2) enhance implementation of the principle of optimisation of protection and safety; (3) strengthen the manufacturers’ role in contributing to the overall safety regime; (4) strengthen radiological protection education and training of health professionals; (5) shape and promote a strategic research agenda for radiological protection in medicine; (6) increase availability of improved global information on medical exposure and occupational exposure in medicine; (7) improve prevention of medical radiation incidents and accidents; (8) strengthen radiation safety culture in health care; (9) foster an improved radiation benefit–risk dialogue; and (10) strengthen the implementation of safety requirements globally.

6.3. WHO

6.3.1. Global Initiative on Radiation Safety in Health Care Settings

WHO has launched the Global Initiative on Radiation Safety in Health Care Settings to mobilise the health sector in the safe use of radiation in medicine (WHO, 2008). This initiative brings together key stakeholders (e.g. health authorities, international organisations, professional and scientific societies) in concerted action. The initiative seeks to complement the International Action Plan for the Radiological Protection of Patients established by IAEA in 2002. The provision of policy guidance to health authorities and the development of practical tools for users of radiation in the medical field will enhance protection of patients and healthcare workers.

The wide use of radiation in medicine calls for a public health approach to controlling and minimising health risks, while maximising the benefits. WHO is giving special consideration to the evaluation of possible health hazards related to the use of radiation. Using scientific evidence, WHO aims to raise awareness by promoting radiation safety in medicine, particularly in terms of preventing unnecessary medical radiation exposure. The main objective of this initiative is to support Member States in the implementation of radiation safety standards in healthcare facilities.

6.4. Multi-society campaigns

6.4.1. Image Gently

Initiated by a group of concerned paediatric radiologists in 2006, Image Gently is an educational, awareness, and advocacy campaign of the Alliance for Radiation Safety in Pediatric Imaging, a coalition of healthcare and regulatory organisations dedicated to providing safe, high-quality paediatric imaging worldwide. The primary objective of the Alliance is to raise awareness in the imaging community of the need to adjust the radiation dose when imaging children. The ultimate goal of the Alliance is to change clinical practice to reduce radiation exposure. Image Gently is directed and run by volunteers, with small financial contributions from the four founding organisations [American Association of Physicists in Medicine (AAPM), ACR, American Society of Radiologic Technologists (ASRT), and Society for Pediatric Radiology (SPR)]. Composed of more than 60 healthcare organisations and agencies, Image Gently attempts to include all stakeholders involved in paediatric imaging, including parents and families. Stakeholders include more than 700,000 radiologists, technologists, medical physicists, and paediatricians. The Alliance’s website contains brochures with information for parents and paediatric protocols for CT, interventional radiology, and nuclear medicine (Applegate and Cost, 2013).

Image Gently and the Society of Nuclear Medicine and Molecular Imaging (SNMMI, 2014) created the ‘Go with the Guidelines’ awareness campaign to encourage community hospitals, academic hospitals, and clinics to observe standardised guidelines on radiopharmaceutical dose for paediatric patients.

6.4.2. Image Wisely

In 2010, AAPM, ACR, ASRT, and the Radiological Society of North America formed a partnership to address concerns about the surge of public exposure to ionising radiation from medical imaging. The result was creation of the Image Wisely campaign, with the objective of lowering the amount of radiation used in medically necessary imaging studies and eliminating unnecessary procedures. To date, more than 19,000 health professionals, 30 medical organisations, and more than 300 medical facilities have taken the Image Wisely pledge to optimise the use of radiation in imaging patients. The Image Wisely campaign initially addressed issues involving dose optimisation in the field of CT by launching a website (http://www.imagewisely.org) that provided information for imaging professionals (including physicians, physicists, and technologists), referring physicians, and patients. In its second phase, Image Wisely collaborated with the American Society of Nuclear Cardiology, SNMMI, and SNMMI–Technologist Section to develop content with respect to dose optimisation in nuclear medicine. Information was generated in the fields of general nuclear medicine, nuclear cardiology, PET-CT, and nuclear medicine physics. As a result, Image Wisely launched its nuclear medicine page in 2012. Campaigns such as Image Wisely and its counterpart in paediatric imaging, Image Gently, not only provide valuable information to its readers regarding dose optimisation in medical imaging, but also raise awareness of its importance among the medical community (Brink and Amis, 2010).

6.4.3. Choosing Wisely

In 2012, the American Board of Internal Medicine (ABIM) Foundation launched the Choosing Wisely campaign with the goal of advancing a national dialogue on avoiding wasteful or unnecessary medical tests, treatments, and procedures. Choosing Wisely centres around conversations between providers and patients informed by the evidence-based recommendations of ‘Things Providers and Patients Should Question’. More than 70 specialty society partners have released recommendations with the intention of facilitating wise decisions about the most appropriate care based on a patient’s individual situation. This campaign helps providers and patients to engage in conversations to reduce overuse of tests and procedures including nuclear medicine.

On 21 February 2013, SNMMI released a list of ‘Five Things Physicians and Patients Should Question’ in nuclear medicine and molecular imaging as part of the Choosing Wisely campaign, led by the ABIM Foundation. SNMMI’s list identified the following five recommendations: (1) do not use PET-CT for cancer screening in healthy individuals; (2) do not perform routine annual stress testing after coronary artery revascularisation; (3) do not use nuclear medicine thyroid scans to evaluate thyroid nodules in patients with normal thyroid gland function; (4) avoid using a CT angiogram to diagnose pulmonary embolism in young women with a normal chest radiograph, and consider a radionuclide lung study ‘[(ventilation/perfusion) V/Q study]’ instead; and (5) do not use PET imaging in the evaluation of patients with dementia unless the patient has been assessed by a specialist in this field (SNMMI, 2013).

6.4.4. Image Green in Korea

There are many concerns about radiation exposure in Korea after the accident at the Fukushima nuclear power plant in 2011 in Japan. In addition, the mass media have created an air of anxiety that jumps on the population’s fear instead of taking a scientific approach. The Korean Alliance for Radiation Safety and Culture in Medicine (KARSM) was founded in September 2011 by eight medical-radiation-related societies (Korean Society of Radiology, KSNM, Korean Society for Radiation Oncology, Korean Association of Radiation Protection, Korean Society of Medical Physics, Korean Society of Radiological Science, Korean Academy of Oral and Maxillofacial Radiology, Korean Radiological Technologists Association) with the aim of promoting, educating, and campaigning about medical radiation safety, so called ‘Image Green’. The activities of KARSM focussed on spreading a culture of medical radiation safety from 2011 to 2012 (http://www.imagegreen.org) (Sung and Shin, 2013; Yoon et al., 2013).

6.5. International guidelines for paediatric radiopharmaceutical administered doses

Dose reduction in paediatric imaging has been a work in progress for nearly a decade. In 2006, the European Association of Nuclear Medicine (EANM) published a new version of their paediatric dosage card for 39 radiopharmaceuticals (Lassmann et al., 2007). In 2008, an amendment with respect to the use of F-18 fluorodeoxyglucose was introduced (Lassmann et al., 2008). Following four consensus workshops conducted in partnership with SNMMI, SPR, and ACR, the 2010 North American Consensus Guidelines for Pediatric Administered Radiopharmaceuticals were developed in 2011 (Gelfand et al., 2011). During the 2012 and 2013 EANM annual congresses, a working group including members of both EANM and SNMMI met to study the possibility of harmonising the guidelines published by the two societies. Although paediatric radiopharmaceutical doses in the North American consensus guidelines differ from those on the EANM paediatric dosage card in several important respects, these meetings have culminated in the development of a set of international guidelines, also referred to as ‘Paediatric Radiopharmaceutical Administration: Harmonization Guidelines’. Twelve radiopharmaceuticals are included in the new guidelines, and others will soon be incorporated. A modified version of the new EANM dosage card incorporating the suggested changes was released in 2014 (Lassmann et al., 2014).

The Nuclear Medicine Global Initiative (NMGI) was formed at an EANM meeting in Milan, Italy in October 2012, and consists of 13 international organisations with direct involvement in nuclear medicine. The underlying objectives of NMGI are to promote human health by advancing the field of nuclear medicine and molecular imaging, encourage global collaboration in education, and harmonise procedure guidelines and other policies that ultimately lead to improvements in quality and safety in the field throughout the world. For its first project, NMGI decided to consider the issues involved in the standardisation of administered activities in paediatric nuclear medicine. A report published in early 2015 provides a review of the value of paediatric nuclear medicine, current understanding of the carcinogenic risk of radiation as it pertains to the administration of radiopharmaceuticals in children, and the application of dosimetric models in children. A forthcoming (Part 2) report will discuss current standards for administered activities in children and adolescents that have been developed by various organisations, and an evaluation of the current practice of paediatric nuclear medicine specifically with regard to administered activities, as determined by an international survey of nuclear medicine clinics and centres. Lastly, the Part 2 report will recommend a path forwards towards global standardisation of the administration of radiopharmaceuticals in children (Fahey et al., 2015).

7. CONCLUSIONS

This paper has here reviewed chronological changes in medical radiation exposure, including nuclear medicine; the implementation status of new international standards for radiological protection (ICRP, 2007a; IAEA, 2014) in the EU and Korea; the principles of justification and optimisation; and international activities on radiological protection of patients from ionising radiation. This includes the work of ICRP Committee 3 on preparing ‘DRLs in medical imaging’; IAEA engagement in several activities including the International Action Plan for the Radiological Protection of Patients; the RPOP website; the Bonn Call for Action; the WHO Global Initiative on Radiation Safety in Health Care Settings; multi-society campaigns including Image Gently, Image Wisely, and Choosing Wisely; and various ongoing activities that provide international guidelines for paediatric radiopharmaceutical administered doses such as the EANM paediatric dosage card and the Nuclear Medicine Global Initiative. In conclusion, in the coming years, numerous efforts will have to be made in these areas to justify and optimise medical procedures using radiation. A greater effort should be made to educate and assure patients, their families, and colleagues that the risks of overexposure of ionising radiation have been taken into account and are well balanced by the benefits in order to avoid deterring patients from life-saving procedures.