Measurements, phantoms, and standardization

Abstract The last 25 years has seen a number of significant developments in the establishment of a measurement infrastructure supporting medical applications of ultrasound. This has allowed manufacturers and users of medical ultrasonic equipment to undertake and compare measurements of key parameters describing the magnitude or strength of the applied ultrasonic field in a meaningful and traceable way: for equipment development, standards compliance, and quality assurance purposes. This paper describes the current state of the art for measurement techniques used to determine the key properties of an ultrasonic field, principally acoustic pressure and acoustic power. Measurement tools and methodologies are described in detail, alongside considerations of how these are likely to develop, shaped by user need. The way that these measurement methods underpin a range of international and national specification standards enabling equipment manufacturers to demonstrate that their equipment is safe and fit for purpose is covered.

[1]  Alastair McKinlay.  The ultrasonic boom—Focus on health and safety , 2007 .

[2]  R. C. Preston,et al.  Development, validation and publication of a complete model for hydrophone/amplifier transfer characteristics. , 2001 .

[3]  Johan M. Thijssen,et al.  P2D-3 Objective Performance Testing and Quality Assurance of Medical Ultrasound Equipment , 2006 .

[4]  T. A. Whittingham,et al.  A survey of the acoustic outputs of diagnostic ultrasound equipment in current clinical use , 1997 .

[5]  Dc Teasdale.  Standards for measurement of wool colour. , 1984 .

[6]  R. C. Preston.  Hydrophone-Based Measurements on a Specific Acoustic Pulse Part 1: Field Characterisation , 1991 .

[7]  Ladislav Dolezal,et al.  An automated system for ultrasound scanner evaluation using PSF analysis of received signal , 2004 .

[8]  Adam Shaw,et al.  A buoyancy method for the measurement of total ultrasound power generated by HIFU transducers. , 2008, Ultrasound in medicine & biology.

[9]  Peter A. Lewin,et al.  Practical Implementations And Technology Of Measurement Devices* , 1993 .

[10]  P. Lewin,et al.  A computerized system for measuring the acoustic output from diagnostic ultrasound equipment , 1988, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[11]  E. G. Radulescu,et al.  Hydrophone spatial averaging corrections from 1 to 40 MHz , 2001, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[12]  D. R. Bacon,et al.  A multiple-frequency hydrophone calibration technique. , 1990, The Journal of the Acoustical Society of America.

[13]  M. McNay,et al.  “forthee....towhom% nosoundisdissonantwhichtellsoflife”% —coleridge , 1999 .

[14]  M. McNay,et al.  Forty years of obstetric ultrasound 1957-1997: from A-scope to three dimensions. , 1999, Ultrasound in medicine & biology.

[15]  D. R. Bacon,et al.  Calibration of medical ultrasonic equipment-procedures and accuracy assessment , 1988, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[16]  Reindert Graaff,et al.  Flat ended steel wires, backscattering targets for calibrating over a large dynamic range. , 2006, Ultrasound in medicine & biology.

[17]  Ch. Koch,et al.  Phase calibration of hydrophones: heterodyne time-delay spectrometry and broadband pulse technique using an optical reference hydrophone , 2004 .

[18]  I. G. Mikhailov.  Methods of measuring the absolute intensity of ultrasonic waves in liquids and solids , 1964 .

[19]  Gail ter Haar,et al.  Therapeutic applications of ultrasound. , 2007 .

[20]  Jacinta E Browne,et al.  Objective measurements of image quality. , 2004, Ultrasound in medicine & biology.

[21]  Ernest L Madsen,et al.  An exposimetry system using tissue-mimicking liquid. , 2008, Ultrasound in medicine & biology.

[22]  D. R. Bacon,et al.  Primary calibration of ultrasonic hydrophone using optical interferometry , 1988, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[23]  S. Robinson,et al.  Extending the frequency range of the National Physical Laboratory primary standard laser interferometer for hydrophone calibrations to 80 MHz , 1999, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[24]  R C Preston,et al.  Standards and measurement. , 2000, Ultrasound in medicine & biology.

[25]  C. Church,et al.  Spontaneous homogeneous nucleation, inertial cavitation and the safety of diagnostic ultrasound. , 2002, Ultrasound in medicine & biology.

[26]  T. Kikuchi,et al.  Quantitative estimation of acoustic streaming effects on ultrasonic power measurement , 2004, IEEE Ultrasonics Symposium, 2004.

[27]  F. Davidson,et al.  Ultrasonic Power Balances , 1991 .

[28]  J M Thijssen,et al.  Performance testing of medical echo/Doppler equipment. , 2002, European journal of ultrasound : official journal of the European Federation of Societies for Ultrasound in Medicine and Biology.

[29]  Bogdan PIWAKOWSKI,et al.  Ultrasound , 1964 .

[30]  D. R. Bacon.  Measurements on a Specific Acoustic Pulse Part 2: Measurements , 1991 .

[31]  Gerald R. Harris,et al.  Output measurements for medical ultrasound , 1993 .

[32]  F A Duck.  Estimating in situ exposure in the presence of acoustic nonlinearity. , 1999, Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine.

[33]  M Hodnett,et al.  Validated ultrasonic power measurements up to 20 W. , 2001, Ultrasound in medicine & biology.

[34]  S P Robinson,et al.  Extending the frequency range of the NPL primary standard laser interferometer for hydrophone calibrations to 60MHz. , 1999 .

[35]  J. Thijssen,et al.  Performance testing of medical ultrasound equipment: fundamental vs. harmonic mode. , 2002, Ultrasonics.

[36]  B Zeqiri,et al.  Development of standard measurement methods for essential properties of ultrasound therapy equipment. , 1994, Ultrasound in medicine & biology.

[37]  R. C. Preston,et al.  PVDF membrane hydrophone performance properties and their relevance to the measurement of the acoustic output of medical ultrasonic equipment , 1983 .

[38]  Robert A Smith.  The importance of the frequency response of a hydrophone when characterising medical ultrasonic fields. , 1986 .

[39]  Mark Hodnett,et al.  Calibration and measurement issues for therapeutic ultrasound. , 2008, Ultrasonics.

[40]  Adam Shaw,et al.  Requirements for measurement standards in high intensity focused ultrasound (HIFU) fields. , 2006 .

[41]  C. Millar,et al.  PVDF reference hydrophone development in the UK-from fabrication and lamination to use as secondary standards , 2000, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[42]  A Shaw,et al.  Standards to support performance evaluation for diagnostic ultrasound imaging equipment. , 2007 .

[43]  A. D. Bond,et al.  The influence of waveform distortion on hydrophone spatial‐averaging corrections—Theory and measurement , 1992 .

[44]  R. Apfel,et al.  Gauging the likelihood of cavitation from short-pulse, low-duty cycle diagnostic ultrasound. , 1991, Ultrasound in medicine & biology.

[45]  Bajram Zeqiri.  Metrology for ultrasonic applications. , 2007, Progress in biophysics and molecular biology.

[46]  R C Preston,et al.  Proposed standard thermal test object for medical ultrasound. , 1999, Ultrasound in medicine & biology.

[47]  B Zeqiri,et al.  A new anechoic material for medical ultrasonic applications. , 2000, Ultrasound in medicine & biology.

[48]  K. Beissner.  On the plane‐wave approximation of acoustic intensity , 1982 .

[49]  G.R. Harris,et al.  The impact of piezoelectric PVDF on medical ultrasound exposure measurements, standards, and regulations , 2000, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[50]  B. Zeqiri,et al.  A Novel Pyroelectric Method of Determining Ultrasonic Transducer Output Power: Device Concept, Modeling, and Preliminary Studies , 2007, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[51]  Tom MacGillivray,et al.  Medical ultrasound: a new metric of performance for grey-scale imaging , 2004 .

[52]  Michael Rinker,et al.  The thermoacoustic effect and its use in ultrasonic power determination , 1996 .

[53]  Francis A Duck,et al.  Medical and non-medical protection standards for ultrasound and infrasound. , 2007, Progress in biophysics and molecular biology.

[54]  Bajram Zeqiri,et al.  Evaluation of a novel solid-state method for determining the acoustic power generated by physiotherapy ultrasound transducers. , 2008, Ultrasound in medicine & biology.

[55]  J. S. Lameris.  Routine quality assurance of ultrasound imaging systems. Report 71 , 1996 .

[56]  M Hodnett,et al.  A new method for measuring the effective radiating area of physiotherapy treatment heads. , 1998, Ultrasound in medicine & biology.