The principle of justification in medical imaging Ola Holmberg, PhD Head, Radiation Protection of Patients Unit (RPOP) Division of Radiation, Transport and Waste Safety (NSRW) National Training Course on Justification and Optimization in Diagnostic X-ray Imaging and Interventional Radiology 18-20 October 2016 Riyadh, KSA
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18-20 October 2016 Riyadh, KSA€¦ · Nuclear medicine 33.5 million procedures annually* Radiotherapy 5.1 million radiotherapy treatment courses annually* * UNSCEAR 2008 Report Global
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The principle of justification in medical imaging
Ola Holmberg, PhD Head, Radiation Protection of Patients Unit (RPOP)
Division of Radiation, Transport and Waste Safety (NSRW)
National Training Course on Justification and Optimization in Diagnostic X-ray Imaging and Interventional Radiology
18-20 October 2016
Riyadh, KSA
Benefits of the use of radiation in medicine
0
1000
2000
3000
4000
5000
6000
7000
1988 2008
130 %
122 %
26 %
Number of diagnostic procedures, million
Collective dose, 1000 man Sv
World population, million
Global increase in the use of radiation
Diagnostic radiology
3.6 billion procedures annually* (incl. dental)
Nuclear medicine
33.5 million procedures annually*
Radiotherapy 5.1 million radiotherapy
treatment courses annually*
* UNSCEAR 2008 Report
Global increase in the use of radiation
More can be done with radiation in medicine
• More equipment • More complex equipment • New technologies and techniques
Single slice CT Multi-Detector CT Film Computed & Digital Radiography Hybrid imaging, PET-CT Image-guided interventional procedures Tomosynthesis PACS, RIS, IMRT, IGRT etc…
Access vary around the world Issues vary around the world Tailored approaches needed
The increasing medical exposure
UNSCEAR 1993
Global annual per caput effective dose
The increasing medical exposure
UNSCEAR 2008
Global annual per caput effective dose
The increasing medical exposure
NCRP160 2009
U.S. annual per caput effective dose
“Do more good than harm”
Radiation can cause harm Radiation saves lives
Short-term effects (deterministic)
Long-term effects (stochastic)
- Carcinogenesis - Hereditary effects - Effects in the
embryo/foetus
“Primum non nocere”
Patient dose and individual risk vary greatly
0.01mSv 0.1mSv 1mSv 10 mSv
Radiography
CT, NM, Image guided interventional
procedures Skin doses –
Image guided interventional
procedures Radiation therapy,
mainly to the target volume
Annual dose from natural background
Increased risk of cancer
Tissue reactions (skin, eye lens,..)
100 mSv
1 000 mSv
10 000 mSv
100 000 mSv
Lethal whole body dose
Radiological procedures
Radiation risk
Medical radiation can cause harm
• Over the last three decades, at least 3000 patients have been reported to be affected by radiotherapy incidents and accidents. This is likely grossly under-reported
• Radiation accidents involving medical uses have accounted for more deaths and early acute health effects than any other type of radiation accident, including accidents at nuclear facilities
• ICRP principles of radiation protection oDose limits don’t apply to medical exposures
oJustification - net benefit for the patient
oOptimization - achieve clinical purpose with appropriate dose management
Radiation risk
Achieve clinical purpose
A need for radiation protection in medicine
“Primum non nocere”
Justification and optimization in medicine
Medical exposure is overwhelmingly the most significant manmade source of exposure to the population from ionizing radiation
Issues around the optimization (e.g. wide variation in doses reported for the same type of CT-scan)
Issues around the justification (a substantial fraction of radiological examinations may be inappropriate)
Justification of medical exposure
• Evidence that many individual medical procedures are lacking in justification and optimization, giving rise to a very significant unnecessary exposure of the world’s population
• A substantial fraction (20% to 40%) of individual radiological examinations may be unnecessary
ICRP identifies three levels at which justification operates:
Level 1 deals with use of radiation in medicine in general
(In practice this is accepted as doing more good than harm, and its justification is taken for granted)
Level 2 deals with specified procedures with a specified objective
(The aim at this level is to judge whether the procedure will improve diagnosis or provide necessary information about those exposed)
Level 3 deals with the application of the procedure to an individual
(The particular application should be judged to do more good than harm for the individual patient)
Justification of medical exposure
• What are the factors behind these unnecessary exposures?
• Lack of knowledge about the patient from referring physician (non-adequate
examination of patient, duplicate examinations)
• Lack of knowledge about the procedure or alternatives (benefits and/or risks)
• Variations in local practice (not based on evidence but on “tradition”)
• Evidence not available to relevant healthcare providers
• Lack of certainty, confidence or experience (radiologist)
• Pressure and expectations from patient
• Referring physician is also the provider of the service (self-referral, economic interest)
• Referring as a safeguard against possible malpractice liability (defensive medicine)
• …
• End result: High and increasing “unnecessary radiation burden” experienced by the global population – arising from different basic “drivers”
“To establish or adopt … standards of safety for protection of health and minimization of danger to life … and to provide for the application of these standards”
IAEA statute
Safety Guides
Safety Requirements
Safety Fundamentals
All Safety Standards go through the IAEA Safety Standards Committees and Commission, and receive formal Member State comments
Fundamental safety objectives and principles for protecting people and environment moral obligation
Requirements that must be met to ensure protection of people and environment legal obligations, "shall"
Recommended ways of meeting the requirements, “should”
o Represent an international consensus on what must constitute a high level of protection and safety
o Mandatory for Member States receiving technical assistance from IAEA
o Used as a basis for many national regulations
o Jointly sponsored by other international organizations, allowing organizations to provide consistent advice and assistance to the various government agencies of their Member States
• Availability of relevant information from the patient’s
previous radiological procedures
International collaboration in developing guidelines - Shared review of the literature - Uniform methodology - Exploring joint approaches to improve their use
IAEA Smart Card/SmartRadTrack project - Developing methodologies to track radiation history
AAA-approach
• Audit
• Reviewing the effectiveness of the referral and related
processes
• New BSS – Radiological review
Critical review of the current practical application of justification (& optimization) for the radiological procedures being performed in the facility
AAA-approach
AAA-approach
International Workshop 2009
• Problem global and regional
• The 3 A’s. Mature enough to start.
• Clarification of Appropriateness
Criteria and Practitioner roles
• Communication of dose and risk
initiative
• Role of patient
There is significant and systemic practice of inappropriate examination in radiology. ------
IAEA meetings 2010
• Steering Panel
Explicitly endorsed
Justification and the 3As
formally for Action Plan
• TM on Justification
Also endorsed
Justification and the 3As
International Conference in Bonn 2012
• Organized by the IAEA, co-sponsored by the WHO
• 536 participants and observers in attendance
• 77 Member States and 16 organizations represented
• Bonn Call for Action issued
• Highlights ten main actions, and related sub-actions,
that were identified as being essential for the
strengthening of radiation protection in medicine
over the next decade.
• The actions are not listed in order of importance.
Action by all stakeholders is encouraged.
International Conference in Bonn 2012
Bonn Call for Action • Enhance implementation of justification;
Apply the 3A’s
• Develop evidence-based criteria
involving all stakeholders
• Implement guidelines globally, ~local
and regional variation
• Decision support tools available at
point-of-care
International Conference in Bonn 2012
Proceedings from Bonn • Including a number of papers on
justification
• Free to download (rpop.iaea.org)
IAEA meetings 2011-15
• Series of TM on development and application of guidelines
• International/Global perspective
• With WHO
IAEA meetings 2011-15
• Scientific papers defining an international approach to