Ongoing work within ICRP in the field of medicine Sören Mattsson Medical Radiation Physics, Lund University and Skåne University Hospital Malmö, Sweden Malmö
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Committee 3: Protection in Medicine C3 is concerned with protection of persons and unborn children when ionising radiation is used for medical diagnosis, therapy, or for biomedical research; also, assessment of the medical consequences of accidental exposures. New formulation (2011): includes protection of staff and public in medicine. 3
Recent work of Committee 1: Tissue reactions and other non-cancer effects of radiation Published in ICRP Publication 118, ICRP statement on tissue reactions / Early and late effects of radiation in normal tissues and organs Threshold doses for tissue reactions in a radiation protection context. Ann. ICRP 41(1/2), 2012. Update of ICRP Publication 41, Non-stochastic effects of ionising radiation (1984) Review tissue effects of ionising radiation implications for radiation protection assessing health risks after accidental or therapeutic exposure 4
Tissues and organs Haematopoietic and immune systems Digestive system Reproductive system Skin Eye Cardiovascular and cerebrovascular system Respiratory system Urinary tract Musculoskeletal system Endocrine system Nervous system 5
Lens of the eye - Cataract induction New evidence for development of lens opacities < 2 Sv Japanese A-bomb survivors Therapeutic RT (both non-malignant disease and cancer) Repeated CT scans Astronauts Residents of contaminated buildings Victims of Chernobyl Radiation technologists and interventional radiologists Interventional cardiologists Earlier: 1) detectable opacities after 5 Sv for chronic exposures and 0.5 2.0 Sv for acute exposures (ICRP, 2007). 2) threshold values for visually disabling cataracts of 2 10 Sv for single brief exposures and >8 Sv for 6 protracted exposures (NCRP, 1989; ICRP, 2007).
Lens of the eye Cataract induction Threshold for acute exposure: ~0.5 Sv with 95% CI including zero Threshold for protracted exposure: ~0.5 Sv with 95% CI excluding zero (but evidence for this pertains mainly to opacities rather than cataracts) posterior subcapsular cataract reflections from dilated iris 7
For occupational exposures: 20*
Circulatory diseases - cardiovascular and cerebrovascular For example, LSS cohort of Japanese atomic bomb survivors show an excess relative risk of mortality from circulatory disease: 0.14 per Sv (95% CI: 0.06 to 0.23) for heart disease 0.09 per Sv (95% CI: 0.01 to 0.17) for cerebrovascular disease Nominal threshold dose of 0.5 Sv proposed for cardiovascular and cerebrovascular disease There is considerable uncertainty about the shape of the dose response at doses below 0.5 Sv 9
Statement on tissue reactions (5) The Commission continues to recommend that optimisation of protection be applied in all exposure situations and for all categories of exposure. With the recent evidence, the Commission further emphasises that protection should be optimised not only for whole body exposures, but also for exposures to specific tissues, particularly the lens of the eye, and to the heart and the cerebrovascular system. 10
ICRP C3 (September 2012) Protection in medicine 16 members (MP=Med.Phys. RT=Radiotherapy NM=Nucl.Med. DR=Diag. Radiol.) Vano ELISEO Prof (Spain) MP Chairman Cosset JEAN-MARC Prof (France) RT Vice-Chairman Rehani MADAN M. Prof (IAEA) MP Secretary Åhlström Riklund KATRINE Prof DR, NM (Sweden) 2009 Baeza MARIO Prof RT (Chile) 2009 Dauer LAWRENCE Dr MP (USA) 2010 Gusev IGOR A. Dr Phys, Dr Biology (Russia) Hopewell JOHN W Prof Radiobiology (UK) Mattsson SÖREN Prof MP (Sweden) Miller DONALD Prof DR (USA) 2010 Ortiz Lopez PEDRO Dr MP Spain) Khong PEK-LAN Prof DR (Hong Kong) 2009 Ringertz HANS Prof DR (Sweden) Rosenstein MARVIN Dr Nucl Eng (USA) Yonekura YOSHIHARU Dr RT (Japan) Yue BAORONG Prof (China) 2009 11
ICRP C3 (September 2012) Protection in Medicine 9 observers (some of them starting in 2011) Georgi Simeonov. European Commission (EC), Luxembourg Dr Ausra Kesminiene. International Agency for Research on Cancer (IARC), France Prof Andre Wambersie. ICRU, Belgium Dr Norbert Bischof /Prof. Jim Malone. IEC Observers Dr Shengli Niu. International Labour Office (ILO), Switzerland Ms Renate Czarwinski IRPA, Germany Dr Alain Rannou. ISO, France Dr Ferid Shannoun UNSCEAR, Austria Dr Maria del Rosario Perez. World Health Organisation (WHO), Switzerland. 12
ICRP C3: 15 publications in 10 years 13
Documents already finished. Approved by Main Commission November 2012 1. Radiological protection in paediatric diagnostic and interventional radiology. Publ 121 To be released in January 2013. 2. Radiological protection in cardiology. Publ 120, 2013. To be released in December 2012. 14
Relevant ICRP C3 publications during the last years P117. Radiological protection in fluoroscopically guided procedures outside the imaging department. Ann. ICRP 40(6), 2010 (released on 13 July 2012) P113. Education and training in radiological protection for diagnostic and interventional procedures. Ann. ICRP 39 (5), 2009 (issued 2011). P112. Preventing accidental exposures from new external beam radiation therapy technologies. Ann. ICRP 39 (4), 2009. 15
Relevant ICRP C3 publications during the last years P106. Radiation dose to patients from radiopharmaceuticals: Addendum 3 to ICRP Publication 53, Ann. ICRP 38(1-2), 2008. P105. Radiological protection in medicine, Ann. ICRP 37(6), 2007. P102. Managing patient dose in multi-detector computed tomography (MDCT), Ann. ICRP 37(1), 2007. P98. Radiation safety aspects of brachytherapy for prostate cancer using permanently implanted 16 sources, Ann. ICRP 35(3), 2005.
P97. Prevention of high-dose-rate brachytherapy accidents, Ann. ICRP 35(2), 2005. P94. Release of patients after therapy with unsealed radionuclides, Ann. ICRP 34(2), 2004. P93. Managing patient dose in digital radiology, Ann. ICRP 34(1), 2004. 17
Relevant ICRP C3 publications during the last years SG2. Radiation and your patient: A guide for medical practitioners, Ann. ICRP 31(4), 2001. SG2b. Diagnostic reference levels in medical imaging review and additional advice, ICRP Supporting Guidance 2. Ann. ICRP 31(4). 2001. P87. Managing patient dose in computed tomography, Ann. ICRP 30(4), 2000. 18
Relevant ICRP C3 publications during the last years P86. Prevention of accidental exposures to patients undergoing radiation therapy, Ann. ICRP 30(3), 2000. P85. Avoidance of radiation injuries from medical interventional procedures, Ann. ICRP 30(2), 2000. P84. Pregnancy and medical radiation, Ann. ICRP 30(1), 2000. 19
Educational area at the ICRP website http://www.icrp.org/page.asp?id=35 Pregnancy Interventional radiology Accidents in radiotherapy CT dose management Digital radiology 20
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ICRP C3 priorities for the next years 22
Committee 3. Work in Progress (I) TASK GROUPS: TG 36: Dose to patients from radiopharmaceuticals TG: Secondary cancers after radiation therapy TG 87: Radiological protection in ion beam radiotherapy, TG 88: Radiological protection in conebeam CT. TG 89: Occupational radiological protection 23 in brachytherapy.
Committee 3. Work in Progress (II) WORKING PARTIES: WP: Justification: Framework for justification in medical uses of ionizing radiation. WP: Occupational protection issues in interventional procedures (fluoroscopy guided). WP: Radiological protection in therapy with radiopharmaceuticals. WP: Diagnostic reference levels for diagnostic and interventional imaging. 24
Effective dose. there is too much overuse and misuse of effective dose in recent years. The document should contribute to solve the problem of improper risk estimation and should include explicitly the appropriate use of effective dose, typical misuse and why it is a misuse. To achieve a real impact, consideration should be given to issue a short clarification statement or an editorial, in a similar way as the statement on tissue reactions and the eye lenses. The upcoming UNSCEAR report on uncertainties in risk estimation should be taken into account.
Future Topics a. Occupational protection in PET/CT and cyclotron use. b. Framework for optimization of individual patients. The original intent was to cover radiation protection based on cumulative dose to an individual for which this topic needs to be kept under review. c. Dose quantities for display in imaging equipment for guidance to IEC. Need for guidance to IEC on dose quantities for interventional, CT, CBCT etc. on a periodic basis. IEC should get good advice which can be converted into engineering design. d. Communication of benefits and radiation risks to medical professionals and public. changes in scenarios occurring with social media. e.? f.?
OBSERVERS UNSCEAR (Ferid Shannoun) IAEA (Madan Rehani) IEC (Jim Malone) WHO (Maria Perez) IARC (Ausra Kesminiene) European Commission (Georgi Simenov)
http://ec.europa.eu/energy/nuclear /radiation_protection/doc/2012_com_ 242.pdf
http://epi-ct.iarc.fr/ Dr. Ausrele Kesminiene Int Agency for Res on Cancer Lyon, France Email: rad@iarc.fr
International Basic Safety Standards The interim edition of the international Basic Safety Standards (BSS) will be adopted by the different organisations
Requirement 36: Responsibilities of registrants and licensees specific to medical exposure Registrants and licensees shall ensure that no person incurs a medical exposure unless there has been an appropriate referral, responsibility has been assumed for ensuring protection and safety, and the person subject to exposure has been informed as appropriate of the expected benefits and risks.
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