ultrasound beam fromation 2009

8/12/2019 Ultrasound Beam Fromation 2009

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G.WayneMoore,B.Sc.,MA,FASE

UltrasoundBeamformationandImageReconstructionAAPM2009Conference

WhatwewillcoverWhatwewillcoverWhatwewillcoverWhatwewillcover

HistoricalPerspectiveofUltrasoundTechnology

UltrasoundandTissueWater

PartitionofUltrasonicImagingEvents

ImageQualityAdvances

UltrasoundSystemArchitectureChanges

BeamformationAnalysisandTestDevice

ModernApproachestoSolvingOldImagingProblems

NewerApproachestoImageReconstruction 2DMatrixArrays

TestFixtureand3DVolumetricImageReconstructionAnalysis

WhatsComingintheFutureforUltrasound

WeWeWeWereJustreJustreJustreJustBagsofWaterBagsofWaterBagsofWaterBagsofWater!!!!

Anarchetypalpersonhasabout40Lof

bodyfluid

25Lareinside75trillioncells

15Lareoutsidethecells(interstitialspaces)

5Linbloodvolume

2LofRBCs

3Lofplasma

UltrasoundandTissueWaterUltrasoundandTissueWaterUltrasoundandTissueWaterUltrasoundandTissueWater

1540m/sec1540m/sec1540m/sec1540m/sec6.56.56.56.5BBBBsec/cmsec/cmsec/cmsec/cm

Stillthelaw!Stillthelaw!Stillthelaw!Stillthelaw!


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PartitionofUltrasonicImagingEventsPartitionofUltrasonicImagingEventsPartitionofUltrasonicImagingEventsPartitionofUltrasonicImagingEvents

TissueTissueTissueTissue----

ultrasoundultrasoundultrasoundultrasound

11

22

DopplerDopplerDopplerDopplerDopplerDopplerDopplerDoppler

ImageImageImageImageImageImageImageImage

ProcessingProcessingProcessingProcessingProcessingProcessingProcessingProcessing

GrayScaleGrayScaleGrayScaleGrayScaleGrayScaleGrayScaleGrayScaleGrayScale

ImageImageImageImageImageImageImageImage

ProcessingProcessingProcessingProcessingProcessingProcessingProcessingProcessing33

ThescanheadorThescanheadorThescanheadorThescanheador

TransducerTransducerTransducerTransducer

SpecializedSignalSpecializedSignalSpecializedSignalSpecializedSignal

ProcessingProcessingProcessingProcessing

44

Color/GrayscaleColor/GrayscaleColor/GrayscaleColor/Grayscale

displaydisplaydisplaydisplayMassStorage:MassStorage:MassStorage:MassStorage:

VCRVCRVCRVCR

CDCDCDCD

PACSPACSPACSPACS

LANLANLANLAN

55

TransmitsignaloutTransmitsignaloutTransmitsignaloutTransmitsignalout

EchosignalreturnEchosignalreturnEchosignalreturnEchosignalreturn

History of Modern Diagnostic Ultrasound

A-ModeM-ModeB-ScanMechanically Steered Real-timeLinear Array Real-timeZero-crossing DopplerSpectral Doppler (FFT)Phased Array Real-timeCW Doppler in Probe Bernoulli EquationColor Flow DopplerTriplex modes of OperationPseudo-ColorColor Angio & Power DopplerHarmonic Imaging & VariantsContrast Media ImagingSpatial Compounding3D Imaging Volumetric4D Imaging Steered Curved ArrayPhase Aberration Correction

t6Incomplexity

1979

1985 1997

2009

3DVolumetriccardiacimage

derivedfrom2DMatrixArray

with2,500elements

pseudoColordisplayidentifies

proximalanddistalechoes

Some3DClinicalAdvantagesSome3DClinicalAdvantagesSome3DClinicalAdvantagesSome3DClinicalAdvantages:

Nogeometricassumptions

Nomentalinterpolations

(cognitivereconstruction)

Providespre-surgicalperspective

Providespost-surgicalperspective

PyramidalvolumeofultrasonicdataPyramidalvolumeofultrasonicdataPyramidalvolumeofultrasonicdataPyramidalvolumeofultrasonicdata


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EvolutionofUltrasoundSystemArchitecture + =

Proprietary

Hardware

CentricDesign

ProprietarySoftwareCentricDesign

SpecializedFrontEnd

GeneralizedBackEnd

SinglePlatform

MicrosoftXPEmbedded

SoftwarePlatform

ChangeofSystemTechnologiesSince1990ChangeofSystemTechnologiesSince1990ChangeofSystemTechnologiesSince1990ChangeofSystemTechnologiesSince1990

ProprietaryHardwareCentric

HybridCentric

ProprietarySoftwareCentric

Software+GeneralizedBackendCentric

Shiftfromanalogtodigitalbeamformers

PA=PreamplifierPA=PreamplifierPA=PreamplifierPA=Preamplifier

ADC=AnalogtodigitalconverterADC=AnalogtodigitalconverterADC=AnalogtodigitalconverterADC=Analogtodigitalconverter

TGCApplication

PAPA

PAPA

PAPA

PAPA

PAPA

PAPA

PAPA

PAPA

PAPA

ADCADC

ADCADC

ADCADC

ADCADC

ADCADC

ADCADC

ADCADC

ADCADC

ADCADC

DynamicT

imeD

elays

128ElementTransducer

10bits36MHz10bits36MHz10bits36MHz10bits36MHz

1024Values1024Values1024Values1024Values

60dBDynamicRange60dBDynamicRange60dBDynamicRange60dBDynamicRange

ThedigitalbeamformerThedigitalbeamformerThedigitalbeamformerThedigitalbeamformer

functionhashistoricallyfunctionhashistoricallyfunctionhashistoricallyfunctionhashistorically

residedinthemainconsoleresidedinthemainconsoleresidedinthemainconsoleresidedinthemainconsole

oftheultrasoundsystemoftheultrasoundsystemoftheultrasoundsystemoftheultrasoundsystem


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Digitalbeamforming2009Digitalbeamforming2009Digitalbeamforming2009Digitalbeamforming2009

Higher element counts were once

restricted by the need to have a

single wire in the probe cable for each

element in the array. Multiplexing the

elements allowed for transducers with

higher element counts and a lower

number of transmit channels in the

beamformer. Current 2D matrix

arrays with element counts of 2,500

necessitated a different approach to

beamforming, and where the

beamforming, or at least parts of it

would take place.

Sub-beamforming

performed in the

probe

100 Channels feeding

& receiving2,500 elements

Would be normally whata standardfront endwould expect to see

High speed serial interface that provides control signals for the sub-beamformere.g., defining delays for each unique element

x (f)x(f)

Time sampling is digital, all else is analog

x

x(f)

BeamformationAnalysisBeamformationAnalysisBeamformationAnalysisBeamformationAnalysisTextTextTextText----fixtureandsetfixtureandsetfixtureandsetfixtureandset----upupupup

Commerciallyavailable

ultrasoundprobeand

systemtestingdevice

usingasinglecrystalto

bothreceivesignalsfrom

theprobeandtransmit

signalsintothesystem

viatheprobe.


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+

-

ComparatorTransducer

Amplifier

Red LEDGreenLED

Threshold Level

Threshold timer

10 mSec

ON OFF

Power On Timer

200 mSec

Target Generator

3-5 cm 10 MHz

5-7 cm 5 MHz

7-9 cm 2.5 MHz

Target Transmitter

TestDevice BlockDiagram

26sec = 2cm 26sec = 2cm 26sec = 2cm

1 0M Hz 3 -5c m 5M Hz 5- 7c m 2. 5MH z 7- 9cm

FundamentalImaging

samplerategapsin

phasedarraysector

display

2nd HarmonicImaging

HarmonicImage

FundamentalImage

Anexampleofexpanding

aperturefocusingusedto

maintainspatialresolution

throughoutdepthoffield

Active aperture changes asa function of depth


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Oldimagingproblems,newimagingapproachesOldimagingproblems,newimagingapproachesOldimagingproblems,newimagingapproachesOldimagingproblems,newimagingapproaches

1540m/sec1540m/sec1540m/sec1540m/sec

6.56.56.56.5BBBBsec/cmsec/cmsec/cmsec/cmStillthelaw!Stillthelaw!Stillthelaw!Stillthelaw!

Transducer

Shadow

Scanning Field

ShadowingObject

ShadowinginPropagationEventsShadowinginPropagationEventsShadowinginPropagationEventsShadowinginPropagationEvents

Objectsthatareveryreflectiveor

veryattenuatingremove

ultrasoundfromtheimagearea

behindthemassproducing

shadows.Theseeventsmarkaspecificinteractionbetween

ultrasoundandtissues,anda

propertyoftheshadowing

tissues.

Transducer

Scanning Field

RefractiveShadow

RefractiveSurface

UltrasoundRefractionattheEdgeofaCircularObjectUltrasoundRefractionattheEdgeofaCircularObjectUltrasoundRefractionattheEdgeofaCircularObjectUltrasoundRefractionattheEdgeofaCircularObject

Circularorcysticstructurescanproducerefractionattheedgeof

thestructure,bendingthebeamintotheobject,producing

shadowsextendingfromtheedge

oftheobject.Thishappenswithachangeinpropagationvelocity,

butdoesnothappenifthereare

novelocitychanges.

Probe

Breast

Lesion

NormalScanLines

SonoCT

ScanLinesSpatialCompoundingSpatialCompoundingSpatialCompoundingSpatialCompounding


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SpatialSpatialSpatialSpatial

CompoundingCompoundingCompoundingCompounding

UsingMultipleUsingMultipleUsingMultipleUsingMultiple

AperturesandAperturesandAperturesandAperturesand

AnglesAnglesAnglesAngles

LimitedFieldsofViewLimitedFieldsofViewLimitedFieldsofViewLimitedFieldsofView

Withastructureidentifyingalgorithm,thesystemlocatesandpositionsmajorstructures,calculatingthe

structurelocationinthecontinuousslicingscanofthe

transducer.Thistechniqueisequivalenttocompound

B-scanningwithoutascanningarm.

SliceMotion

SieScapeSieScapeSieScapeSieScape bySiemensbySiemensbySiemensbySiemens


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ComplexBeamformingin4DSystemsComplexBeamformingin4DSystemsComplexBeamformingin4DSystemsComplexBeamformingin4DSystems

60 Degree Angle

20 Degree Angle TextTextTextText----fixtureandsetfixtureandsetfixtureandsetfixtureandset----upfor4DImageFormationAnalysisupfor4DImageFormationAnalysisupfor4DImageFormationAnalysisupfor4DImageFormationAnalysis

UsingaPhilipsiE33UltrasoundSystemandX7UsingaPhilipsiE33UltrasoundSystemandX7UsingaPhilipsiE33UltrasoundSystemandX7UsingaPhilipsiE33UltrasoundSystemandX7----2tprobe2tprobe2tprobe2tprobe

Inordertocreatereal-time 4Dultrasoundimages

(i.e.,threespatialdimensionsplusmotion),volume

datasetsmustbeacquired,processedand

displayedataratehigherthanthecapacityofthe

humaneyetoretainavisualimpression

2D Matrix Array 2,500 elements

Frame rate paces random access to the array

BenchSetBenchSetBenchSetBenchSet----upupupup

Nickel(PVDF)Nickel(PVDF)Nickel(PVDF)Nickel(PVDF)

TektronixScopeTektronixScopeTektronixScopeTektronixScope

RFPowerAmplifierRFPowerAmplifierRFPowerAmplifierRFPowerAmplifier

Probe/NickelFixtureProbe/NickelFixtureProbe/NickelFixtureProbe/NickelFixture


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TEE/NickelInterfaceTEE/NickelInterfaceTEE/NickelInterfaceTEE/NickelInterface

Position/PressurePosition/PressurePosition/PressurePosition/Pressure

ControlMechanismControlMechanismControlMechanismControlMechanism

1 2 33

2

2

2

3

3

X7-2t

5x5elementsub-aperture

PhilipsX7-2tprobe

2500elements

100channels

ArrayCarrierArrayCarrierArrayCarrierArrayCarrier

TipCollarTipCollarTipCollarTipCollar

TransducerTransducerTransducerTransducer

ArrayArrayArrayArray

CoaxtoCoaxtoCoaxtoCoaxto

FlexCircuitFlexCircuitFlexCircuitFlexCircuitInterfaceInterfaceInterfaceInterface

PottedPassivePottedPassivePottedPassivePottedPassiveComponentsComponentsComponentsComponents

InsidetheX7InsidetheX7InsidetheX7InsidetheX7----2t2t2t2t

FlextoArrayFlextoArrayFlextoArrayFlextoArray

InterfaceInterfaceInterfaceInterface FlexCircuitFlexCircuitFlexCircuitFlexCircuit

BackingBackingBackingBackingMaterialMaterialMaterialMaterial

GoldFoilGoldFoilGoldFoilGoldFoil

I/OconnectionforI/OconnectionforI/OconnectionforI/Oconnectionfor

IntegratedCircuitIntegratedCircuitIntegratedCircuitIntegratedCircuit

NonNonNonNon----insulatedinsulatedinsulatedinsulatedBBBBmmmm

thickbondingwires*thickbondingwires*thickbondingwires*thickbondingwires*

InsidetheX7InsidetheX7InsidetheX7InsidetheX7----2t2t2t2t CCD


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SystemInterfaceSystemInterfaceSystemInterfaceSystemInterface

BatterypoweredBatterypoweredBatterypoweredBatterypoweredDiffPreDiffPreDiffPreDiffPre----amplifieramplifieramplifieramplifier

goodhighfreqgoodhighfreqgoodhighfreqgoodhighfreqdetectionandCMRR*detectionandCMRR*detectionandCMRR*detectionandCMRR*

Detecting xmit, generatestarget, gets amplified by

the RF amp* common mode rejection ratio

InputsignalfromNickel4Bsecburst@5MHz

Noise feed throughfrom RF amp

Acoustic signal onlyReceive out of ultrasound system

Noise + Acoustic

Nickeltransmitpulsematcheseveryother

systemtransmitcreatingonelinegapsin

sectordisplayshownabove

NickelpulseNickelpulseNickelpulseNickelpulse

UltrasoundsystempulseUltrasoundsystempulseUltrasoundsystempulseUltrasoundsystempulse


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3DimageNickeltransmitpulsedisplayed

3Dimagerotated

Nickeltransmit

pulsedisplayedacrossallslices

sector switching

Mixedmode(ColorFlowDopplerandImaging)Reducedframerateapproximatelymatchesevery

Nickelpulsetherebyfillingin eachsectorline

NiSys NiSysSignalInFront


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SignalInMiddle SignalInBack

SoWhatisComingNext?SoWhatisComingNext?SoWhatisComingNext?SoWhatisComingNext? Majorinnovationinultrasoundwillwillwillwill slow,but


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(1) 2DMatrixArrayswillbedevelopedforbroaderclinicalapplication

(2) Designandoptimizationofcapacitivemicro-machinedultrasonic

transducers siliconsubstratesmaynotbetheavenue

(3) Extendedsub-beamformer+CMUTs

ultrasoundstillmustremaincompetitivewithotherultrasoundstillmustremaincompetitivewithotherultrasoundstillmustremaincompetitivewithotherultrasoundstillmustremaincompetitivewithother

advancedimagingmodalitiessuchasMR,soadvancedimagingmodalitiessuchasMR,soadvancedimagingmodalitiessuchasMR,soadvancedimagingmodalitiessuchasMR,soStandard Imaging

System Connector

Standard Ultrasound Cable

1. Wrist-MountedConnector

2. Flat Flex Cable

3. Small-profile,finger-mounted array

Forexample,extensionsofultrasoundForexample,extensionsofultrasoundForexample,extensionsofultrasoundForexample,extensionsofultrasoundapplicationsbasedonclinicalneedapplicationsbasedonclinicalneedapplicationsbasedonclinicalneedapplicationsbasedonclinicalneedandandandand

costeffectivenesscosteffectivenesscosteffectivenesscosteffectiveness

Nobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the BlackNobility of Soul Never Kept a Business in the Black

ENDPRESENTATIONENDPRESENTATIONENDPRESENTATIONENDPRESENTATION

ThankYouThankYouThankYouThankYou

ultrasound beam fromation 2009

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