There are concerns within the UK's radiology community that new proposed safety measures could damage the provision of magnetic resonance imaging (MRI).
The majority of audience members (66.7%) of a debate at the British Institute of Radiology's UK Radiological Congress voted for the motion that current and future provision of MRI will be damaged by proposed future safety. A large proportion (76.8%) also agreed that the development of interventional treatments would be limited if rapid imaging sequences are forbidden by the European Directive.
Dr Stephen Keevil of King's College, London argued for the motion, criticising the absolute limits of the European Union's (EU) directive concerning protection of workers from electromagnetic fields (EMF), which include exposure limits for time-varying fields. The directive must be adopted into the law of all member states by 2008. Keevil told congress delegates that standing close to an MR scanner during imaging involves exposure to time-varying fields, due to the gradients, in excess of these new limits. He argued the directive would preclude many current and future interventional MR procedures and impact on imaging of children, anaesthetised patients and others needing constant care. Alternative X-ray guided procedures could in some cases, such as lengthy paediatric interventions, involve significant risk due to radiation exposure.
Keevil also said the EMF limits are based on ultraconservative interpretation of limited data, with some of the original work neither peer-reviewed or reproduced.
In response, Arwel Barrett of the Health and Safety Executive (HSE) Field Operation Directorate, Bootle, UK, said allegations that the EU directive would prohibit MRI were misleading, and demonstrated a lack of understanding by some clinical practitioners of health and safety at work regulations. Barrett argued that companies supplying MRI equipment have put insufficient thought into how they are to be operated - including servicing, cleaning and maintenance - to protect staff. He discussed how the use of MR compatible cleaning/disinfectant equipment with long handles and changes to custom and practice of patient management would remove the need for staff to enter the bore of the magnet where they may exceed the relevant limits.
Audience members, however, mostly sided with Keevil, with the majority voting either that exposure met by MRI staff was not a matter of concern (42.5%) or generally not a matter of concern (37%).
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