cocir position on eu directive 2004/40/ec umeå, 7 october 2009 hans baartman, toshiba medical...

COCIR Position on EU directive 2004/40/EC

Umeå, 7 October 2009

Hans Baartman, Toshiba Medical Systems Europe and chair of COCIR EMF-TaskForce

of totalUmeå conference, 7 October 2009

What is COCIR?

COCIR is the European Trade Association representing European Leading companies and national trade associations

in the field of Radiology, Electromedical equipment &Healthcare IT solutions

« The European Committee for the Radiological, Electromedical and Healthcare IT Industry »


Range of products & services covered by the COCIR members

• Medical Imaging equipment such as– Computed Tomography– Magnetic Resonance Imaging – Diagnostic Ultrasound – Radiotherapy

• Electromedical equipment such as– Patient Monitoring– Intensive Care equipment– Electro Surgery

• Healthcare IT solutions such as – Electronic Archives, e.g. PACS– Hospital Information Systems– E-Health solutions


COCIR Members Today


Directive 2004/40/EC• Is developed to safeguard workers from adverse

effects from EMF radiation generated by the use of electric and electronic equipment.

• COCIR supports such initiative.• BUT: limits in present directive hamper the use

and further development of MR equipment and its application.


Exposure levels• Directive versus MRI exposure levels

Basics on MRI Technology


Basics of MRI• MR scanners belong to the group of Nuclear

Magnetic Resonance (NMR) equipment• Use the same principle: Tissue is seen as dipole

magnet that spins (rotate) around its axis and once such a dipole is energized it emits EMF radiation when returning to its stable state.

• With human tissue mainly containing water, MR imaging equipment concentrates itself to measure the response of hydrogen protons.

• Based on the difference in response throughout the body, tissue characterization can be performed.


• MRI uses 3 sections of EMF spectrum– Static field, to align all protons– Low frequency EMF, through switching gradients, to define

position and receive multiple signals from one energizing pulse

– High frequency EMF, RF, to energize protons

• Major difference between MR equipment and other equipment affected by the directive:

• MR equipment intentionally uses EMF radiation

Basics of MRI


Basics of MRI• Coil arrangements

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Static field coilStatic field coil ((Superconducting coil)Superconducting coil)

Gz coilGz coil

Gz coilGz coil

Gy coilGy coil

Gx coilGx coil Gx coilGx coil

Gy coilGy coil Transmit coilTransmit coil

Receive coilReceive coil

Static fieldStatic field

BB00


• MRI is located in a controlled environment– MRI is placed in Faraday cage to avoid disturbance from

external sources like Radio, TV & GSM signals

Basics of MRI



external sources like Radio, TV & GSM signals– MRI uses strong magnetic field, consequently steel objects

becomes projectiles– MRI magnet field has a stray field with restricted access to

public, because of metal implants.

Basics of MRI



external sources like Radio, TV & GSM signals– MRI uses strong magnetic field, consequently steel objects

becomes projectiles– MRI magnet field has a stray field with restricted access to

public, because of metal implants. – MRI magnet is a pressure vessel filled with about 1500

Litre liquid Helium

Basics of MRI

Regulatory Framework


Experience combined with regulatory framework

• Over a period of 30 years, the MR community has collected a vast experience with this technology imaging over 500 million patients without evidence of harm to workers due to EMF exposure.

• MR equipment is regulated in Europe by the Medical Devices Directive 93/42/EC.

• The international IEC/EN 60601-2-33 standard is addressing the protection of patients and workers by establishing limit values for time-varying electromagnetic fields.


Training & work instructions

• MR equipment in hospitals, medical clinics and research facilities is always installed in a controlled environment.

• Professionals operating these installations are highly educated and received dedicated training courses on the physics behind MR imaging.

• Most of these workers are subject to a Continuous Medical Education system and therefore up to date knowledge through training and work instructions is always in place.


Risk assessment• Within the various system development stages

appropriate risk assessment is vital.• Such process is monitored by notified bodies as

a part of the good manufacturing practice.

• Prior to every patient examination and/or system test a risk benefit analysis is performed.

Trends in MRversus

minimizing exposure by design


1990 2000 20091980

MRI innovations over 30 years

0.2 T 1.5 T 3 T 7 T


Static magnetic fieldstrength consideration

• signal to noise ratio of the image is proportional to the static magnet field strength: S/N ~ Bo

• or (for same S/N) scan time ~ 1 / (B0)2

Example:• S/N @ 3 T= 2*S/N @ 1.5T

(i.e. twice image quality, better diagnosis)

or• scan time @ 3T=1/4 @ 1.5T

(i.e. 4 x faster -> new applications)

or• 512x512 pixel @ 3T instead of 256x256 @ 1.5T

(i.e. better diagnosis)


1983 1986 1990 1994 1997 2000+

Imax [A] 150 160 300 300 300 > 500

Umax[v] 120 250 300 600 800 > 2000

kVApeak 18 40 90 180 240 > 1000

Grad. Strength [mT/m] 3 10 15 20 25 > 40

rise time [ms] 1.5 1.5 1 0.5 0.4 < 0.2

Slew rate [T/m/s] 2 6.6 15 40 62 > 200

Increase of gradient performance over time


Theoretical options to reduce EMF exposure to MR-workers

• Options to minimize exposure to MR-worker:– reduce stray field distribution – reduce field strength opposite trend– reduce system size opposite trend

improve openness

– increase distance to field source by design disables certain

applicationsintervention, therapy, fMRI…

opposite trendto improve patient comfort

of totalUmeå conference, 7 October 2009 23

NRI’s 7.0T Human In-vivo Ultra High Resolution Image

Cellebellum

4thVentricle

Substantia Nigra

Medial Lemniscus Nucleus

Solitary Tr.Corticospinal

Tracts

Cerebral Peduncle Optic

Chiasm

OlivaryNucleus

Red Nucleues Superior Cerebella Peduncle

AnteriorCommissure

SubthalamicNucleus

Ventral Tegmental

Area

Z. H. Cho, NRI – Neuroscience Research Institute, Gachon University of Medicine & Science, Korea, 2006

COCIR View on EMF Directive


Applications at risk

• 50.000 MRI examinations per year in the EU hampered by current limit values :– Emergency cases (e.g. coma patients…)– Special populations (e.g. babies…)– Interventional applications

• Research and innovation like molecular imaging at manufacturing sites in Europe penalised, compared to rest of the world.

• If currents induced by movement in the static field are inside the scope of the directive, operating MR in Europe will become illegal.


• MR technology (existing since 1979) is responding to clinicians needs and has compiled proven benefits to citizens and patients (no evidence-based data about incidents)

• EMF generated by an MRI device is intentional, it is not a side-effect

• MR equipment is used in a controlled environment• All MR workers are trained on the possible health effects of

the exposure to EMF and equipment is designed as per IEC standard

• IEC standard is considered the “state of art” regarding safety and performance of MR equipment for patients and workers (amendment on safety of workers published in JOCE in 2008)

Reasons why MRI workers need a conditionnal Exemption


COCIR Recommendation• Pre-requisite:

– It is essential that MR (major advance in health care technology) is not threatened by legislation when concerns can be addressed through appropriate guidance to medical and service personnel (Guidance docoments have been developed by radiologists together with other healthcare workers)

• In view of the scientific evidence available, • In view of the specificities of the MR sector,• In view of the existing safeguards specifically developed by

IEC and CENELEC for the safety of MR equipment,

COCIR calls for a conditional exemption of MR workers considering that appropriate

training and work instructions are in place.

Thank you for your attention

More information can be found on: www.cocir.org

cocir position on eu directive 2004/40/ec umeå, 7 october 2009 hans baartman, toshiba medical...

Documents

total ume conference

mri technology slide

electronic equipment

ec ume

industry slide

mr imaging equipment

basics of mri mr scanners

mri exposure levels