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TNO Quality of Life
>29.0°C
<19.0°C
20.0
22.0
24.0
26.0
28.0
HITU - Standardization - Metrology
WHY / WHAT ??
R.T. HekkenbergGuest at TNO, NL
A standard alone is not enough
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation
The reactions were:-You are schrunken a lot(obviously the cactus is normal sized)
-What a large cactus(obviously we were normal sized)
We clearly miss an agreement
of interpretation of sizes
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation• So products may work as expected (specifications)• To show compatibility with other equipment• To avoid inferior quality• Non-standardized products may be (more) dangerous
• Helps to understand and compare research results
• Essential for Governments, Regulators, Legal professions
• Enable multi-market access, important benefit to business
• Provides a solid foundation for new technologies
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation
• They contribute to the enhancement of our daily lives - often invisibly
• Usually Standards are “User confidence builders”
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HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisationApplication of Ultrasound in MedicineUltrasound in Medicine
• Diagnostic Ultrasound• Physio Therapeutic Ultrasound• Cancer treatments (HITU)• Thrombolysis• Lithotripsy• Histotripsy• Bone repair• Drug delivery (HITU)• Foetal monitoring• Fat removal• Cosmetic surgery• Ultrasonic cleaning
ISTU, New York, 2011-04-12 5
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation, Research
EN 45502‐1: 1997 Safety of implantable devices (pacemakers) Test: 30 minutes: ultrasound energy of 500Wm‐2
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation, Research
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Guidance on reporting ultrasound exposure conditions for bio-effect studies,
Gail ter Haar, Adam Shaw and others in the UFSUMB,UMB Vol 37, No 2,2011
This guidance is intended to encourage a better practice among researchers
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation, Research
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Recommendations for studies:
A: that attempts to demonstrate correlation or lack of correlation Must include (local) ultrasound field parameters
B: preliminary (non-quantitative) studiesReport output levels quoted in the user manual or on-screen
indicationsof ‘‘output’’ or of TI or MI is acceptable
C: for any study:The measured values of any acoustic quantity should always bereported, even when these are to derive MI and TI values.
D: whenever possiblethe temperature rise in the region of interest in tissue or in a physical phantom should be determined
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation, Research
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Recommendations for studies:
E: AlwaysExplain fully how estimated values of in situ acoustic pressure or intensity are derived.
F: AlwaysThe transmission loss of the propagation path should be used to estimatethe relevant in situ values used for the biological effects.
G: If a TI or MI is calculated for use as an exposure quantityThe index should refer to be the “Local index” and calculated as such. The method used should be explained including a worked example.
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Aspects related to Safety
Ultrasound system
Safety aspectsdue to
performance
Safety aspectsdue to
application
Know what ultrasound can cause
Quality & stability of performanceQA
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
International Standardisation (IEC)
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
International Standardisation (IEC)
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Device Safety StandardsIEC 60601-1-1General requirements
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ISO/IEC 14971Risk-Assessment
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Device Safety StandardsIEC 60601-1-1General requirements
IEC 60601-2-37Particular Diagnostic
IEC 60601-2-5 Particular Physiotherapy
IEC 60601-2-62Particular HITU
IEC 60601-2-36Particular Lithotripsy
IEC 60601-2-2Surgical Systems
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ISO/IEC 14971Risk-Assessment
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Device Specs StandardsIEC 60601-1-1General requirements
IEC 60601-2-37Particular Diagnostic
IEC 60601-2-5 Particular Physiotherapy
IEC 60601-2-62Particular HITU
IEC 60601-2-36Particular Lithotripsy
IEC 60601-2-261289-1 and -2
Surgical Systems
IEC 62359requirements &
methodsIEC 61689
requirements & methods
IEC 61846requirements &
methodsIEC 61847
requirements & methods
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
IEC 60601-1-1General requirements
IEC 60601-2-37Particular Diagnostic
IEC 60601-2-5 Particular Physiotherapy
IEC 60601-2-62Particular HITU
IEC 61161Ultrasonic power
IEC 62127-1Hydrophone use
IEC 62255Ultrasonic power
In HITU
IEC 62256Hydrophone use
In HITU
IEC 60601-2-36Particular Lithotripsy
IEC 62359requirements &
methodsIEC 61689
requirements & methods
IEC 61846requirements &
methodsIEC 61847
requirements & methods
IEC 60601-2-2Surgical Systems
Output Measurement Standards
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TS-IEC 61949Non-linear
IEC 62649 TRHITU Requirements
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Why do we need standardisation Application specific Safety Considerations
Application Safety consideration based on
Diagnostic
Physiotherapy
Thermal (TI) or Mechanical (MI) Indices
Acoustic info, Beam non uniformity andUnwanted radiation
Acoustic and beam dimensional infoTemperature measurements
Therapy (HITU)
All these need: Output & Beam characterisation
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Large variety of Transducers
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Large variety of Ultrasonic fields
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Different types of Hydrophones
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
“Standard” Labs: Hydrophone calibrationINMETRO
Reciprocity
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PTB
Interferometry
NMIJ
CSIC NPL
NIM
FORCE
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Output Measurement Standards
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IEC 60601-1-1General requirements
IEC 60601-2-37Particular Diagnostic
IEC 60601-2-5 Particular Physiotherapy
IEC 60601-2-62Particular HITU
IEC 61161Ultrasonic power
IEC 62127-1Hydrophone use
IEC 62255Ultrasonic power
In HITU
IEC 62256Hydrophone use
In HITU
IEC 60601-2-36Particular Lithotripsy
IEC 62359requirements &
methodsIEC 61689
requirements & methods
IEC 61846requirements &
methodsIEC 61847
requirements & methods
IEC 60601-2-2Surgical Systems
TS-IEC 61949Non-linear
IEC 62649 TRHITU Requirements
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Standards related to HITU
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IEC 60601-1-1General requirements
IEC 60601-2-62Particular HITU
IEC 61161Ultrasonic power
IEC 62127-1Hydrophone use
IEC 62255Ultrasonic power
In HITU
IEC 62256Hydrophone use
In HITU
TS-IEC 61949Non-linear
IEC 62649 TRHITU RequirementsTC87 WG 6
TC87 WG 6
TC87 WG 6
TC87 WG 8
TC87 WG 14
TC87 WG 8
SC62D PT 60601-2-62
TC62 SC62A
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Set-up of the IEC 60601-2-62 standard (1)
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- Scope- Definitions- Essential Performance- Instructions for use- Warnings and Safety notices- Protection against Electrical Hazards- Protection against unwanted and excessive radiation HAZARDS
Ultrasonic energyUnwanted ultrasound radiationUnintended heating of tissueUnintended cavitational effects on tissue
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Standards in the field of HITU
DEFINITION:EQUIPMENT for the generation and application of ultrasound to a patient for therapeutic purposes with the intention to destroy, disrupt or denature living tissues or non-tissue elements (liquids, bubbles, micro-caps…). The ME EQUIPMENT aims notably at making treatments through actions of ultrasound having mechanical, thermal and more generally physical, chemical or biochemical effects.
Are there major differences with other ultrasound modalities?
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Essential Performance requirements lists sources of unacceptable risk
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Free from the display of incorrect numerical values associated with the therapy to be performed.
Free from the production of unwanted ultrasound output.
Free from the production of excessive ultrasound output.
Free from the reflection of excessive ultrasonic power at the transducer-patient interface due to inadequate coupling
Free from the production of unwanted thermal or mechanical tissue damage in or distal to the REGION OF INTEREST.
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Effects on human tissue shall be given:
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Unintended heating of tissue
Unintended cavitational effects on tissue
• total entry power• entry effective intensity• the spatial peak temporal average intensity• the spatial peak pulse average intensity• the beam width at focus• the focal depth • the side-lobe peak temporal-average intensity
and its position relative to the position of the focus• the pre-focal peak temporal-average intensity
• total entry power• temporal-maximum output power• ratio peak to average pressure• entry effective intensity• the peak rarefactional acoustic pressure
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Calibration acoustic output power
BalanceBalance
Absorber
Power: P = m⋅ g⋅ c(T)
Radiation conductanceG = ∆Pavg / Ueff
2
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Calibration acoustic output power at HITU levels
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EU Joint Research Project:PTB, INRIM, UME, NPL
0,5-3 MHz5-150 Watt
Rel Exp. Uncertainty: 4,5-15,2%
Buoyancy method
NPL
Radiation ForcePTB
INRIM
UME
http://www.ptb.de/EURAMET-JRP7
See also contributions at ISTU from Haller, Jenderka, Shaw
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Power measurements up to 20 WUncertainties can rise
• Gas / dust in the water (cavitation)
• Temperature increase, esp. at high power
• Air movement and vibrations
• Streaming effects
• Absorption in the water path
• Unwanted reflections of ultrasound
• Diverging beam
• Misalignment of ultrasound to target
• Reproducibility of the power to be measured
Up to
• 20%
• 2%
• 0,5%
• 2%
• 1%
• 5%
• > 25%
• 2%
• 2%
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X
HITU
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Set-up of the IEC 60601-2-62 standard (2)
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- Accuracy of controls: Targeting accuracy
- Usability: Device type specific markingsOutput control Targeting accuracyUnintended output levels
- Hazardous situations and fault conditions (imaging equipment)- Electromagnetic compatibility
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Device type specific markings to be displayed
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(but not limited to) may be:
a) The expected temperature rise in the FOCUS during the treatment
b) The ENTRY POWER at the treatment setting
c) The ENTRY EFFECTIVE INTENSITY during the treatment
d) An indication in case cavitation occurs at the TARGET LOCATION
e) A display of the level of the reflected power
f) An indication of the THERMAL EQUIVALENT TIME
∫ °−='
0
)43)((43
tCtTk dtRt
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Determination of temperature rise in tissue mimics
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NPLAdam Shaw
ToshibaSatoshi Yamazaki
TNO
10 mm
80 mm
Puls-echo transducer
Therapy transducer26 mm
Region of interest
TNO
Lateral temp rise TMM 3 MHz
012
3456
78
-20 -10 0 10 20r (mm)
∆T
(deg
r. C
)
IR-measuredTheoreticalUS-measured
60 s heating; depth 11mm
Also:- MR systems- Modelling theories
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Relevant information to be displayed
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Targeting accuracy
An advice about the localization device to be used to localize the target shall be given.
The uncertainty of the positioning device to position the focus of the ultrasonic beam to the target location shall be given
Here the performance of the imaging equipment is important
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Ultrasound Device Performance Standards (IEC)
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IEC 61206 (TS)CW Doppler
IEC 61390 (TS)Performance Pulse Echo
IEC 62462 (TS)Maintenance
Physiotherapy
IEC 61391-1 Performance Pulse Echo
IEC 61689Performance Physiotherapy
IEC 61895 (TS)Performance
Pulsed Doppler
IEC 61391-2Performance Pulse Echo
IEC 61685Flow DopplerTest object
IEC 61266Hand held Doppler
IEC 61847Surgical Systems
IEC 61846Lithotripters
IEC 62649 (DTR)HITU
IEC 62558 (TS)Draft 3D Phantom
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Ultrasound Device Performance Standards (IEC)
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IEC 61390 (TS)Performance Pulse Echo
IEC 61391-1 Performance Pulse Echo
IEC 61391-2Performance Pulse Echo
IEC 62649 (DTR)HITU
IEC 62558 (TS)Draft 3D Phantom
IEC 60601-2-33Particular for MRI
ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Traceable measurements
are a must
Any value(Power, Pressure, Intensity,
Temperature, Image quantities)
Comparing (QA)With previous measurements
or colleagues
ConfirmationTo
Standards
Key comparisons(CIPM)
MetrologyPrimary standards
Proper uncertainty estimates
Effective trade between Nations
(MRA)
Traceability
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Measurement facilities with a lack of traceability?? Medical UltrasonicsMedical Ultrasonics
• Ultrasonic Output Measurements
• Calibration Acoustic Output Power
• Calibration of hydrophones
• Measurement of high power
• Measurement of temperature
• Measurement of high pressures
• Measurements without synchronisation
• Measurement of air coupled Tx
• Performance test objects (sensitivity & dimensions)
• Increasing market in home care and cosmetics
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ISTU, New York, 2011-04-12HITU - Standardization - Metrology: WHY - WHAT
Measurement of Medical UltrasoundMedical Ultrasound
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