Fundamentals of ultrasound practice - StudentVIP · • 2000s - Introduction of 3D/4D ultrasound,...

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1. THEMEDICALIMAGINGDEPARTMENT 3

2. THEHISTORYOFULTRASOUND 4

3. ULTRASOUNDEDUCATION 4

4. THEAUSTRALIANHEALTHCARESYSTEM 6

5. MEDICALTERMINOLOGY 8

6. ULTRASOUNDSCANPLANES 10

7. PATIENTPOSITIONING 12

8. VITALSIGNSANDPATIENTMONITORING 12

9. INFECTIONCONTROL 14

10. COMMUNICATION 15

11. SAFEMOVINGANDHANDLING 16

12. ERGONOMICS 18

13. ULTRASOUNDPHYSICS–SOUNDWAVES 18

14. ULTRASOUNDPARAMETERS 20

15. ULTRASOUNDIMAGEGENERATION 20

16. DISPLAYMODES 21

17. ARTEFACTS 22

18. BIOEFFECTS 23

19. THEULTRASOUNDMACHINE 24

20. THEULTRASOUNDEXAMINATION 24

21. UPPERABDOMENULTRASOUNDEXAMINATION 26

22. RENALULTRASOUNDEXAMINATION 29

23. MUSCULOSKELETALULTRASOUNDEXAMINATION 32

24. THYROIDULTRASOUNDEXAMINATION 34

25. OBSTETRICULTRASOUNDEXAMINATION 35

26. GYNAECOLOGYULTRASOUNDEXAMINATION 39

27. BREASTULTRASOUNDEXAMINATION 43

28. SCROTALULTRASOUNDEXAMINATION 45

29. VASCULARULTRASOUNDEXAMINATION 47

30. MEDICOLEGALISSUESINMEDICALSONOGRAPHY 50

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1. THEMEDICALIMAGINGDEPARTMENT

Medicalimagingistheprocessofimagingthebodyinamedicalsettingtodiagnoseinjuryordisease.Itis

splitupintotwocategories:diagnosticortherapeutic.

Medicalimagingmodalitiescaneitherbeionisingornon-ionising.Ionisingradiationisenergyproducedfromanimagingtechniquethatalsointeractswithtissue.Itisradiationthathasenoughenergytocause

anatomtobecomechargedorionised(losesanelectron).

• ConventionalRadiography

- Thefirstmedicalimagingmodality

- WilhelmRoentgendiscoveredx-rayson8Nov1895

- Imageproducediscalledaradiograph

- Itusesx-raysasanenergysource

- X-raysareattenuatedwhentheyinteractwithtissue:canbescatteredorabsorbed

- Radiolucent:appearsdarker,lessattenuation

- Radiopaque:appearswhiter,moreattenuation

• Fluoroscopy

- Usesx-raysasenergysource

- Contrastmediahelpsimprovevisualisation

- Providesreal-timeimaging

• Mammography

- Radiographyofthebreast

- Useslowerx-rayenergy

• ComputedTomography(CT)

- Firstavailablein1970s

- X-rayspassthroughpatientusingrotatingx-raytube

- Tomographicimageproduced:“slice”ofpatient

- Highradiationdose

• NuclearMedicine

- Usesgammax-rays

- Functionalimaging

- Radioisotopeisgiveneitherorally,injectedorinhaledasaradio-pharmaceutical

- Radioisotopedistributesitselfaccordingtophysiologicalfunction

• MagneticResonanceImaging(MRI)

- Usesprotonsinatomstoproduceimages

- Usespowerfulmagneticfieldsandradio-waves

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- Non-ionising

- Tomographicimageproduced

• Ultrasound

- Useshighfrequencysoundwaves

- Soundgeneratedfromtransducer,reflectedsoundwavereturnstotransducer

- Pulseechoprinciple

2. THEHISTORYOFULTRASOUNDDiagnosticultrasounduseshighfrequencysoundwavestoviewandassessstructuresandorganswithin

thebody.

• 500BC-Pythagorasobservedarelationshipbetweensound,pitchandfrequency.Heinventedan

earlysonometer:adeviceusedfordemonstratingtherelationshipbetweensoundfrequency

producedbyapluckedstringandthetension,lengthandmassofthestring

• 400BC-Archytasstudiedpitchrelatedtomovementofvibratingair

• 350BC-Boethiuscomparedsoundwavestoripplesofwater

• 1500-LeonardoDaVincidiscoveredthatsoundtravelsinwavesandtheangleofincidenceisequal

totheangleofreflection

• 1638-GalileoGalileibeganstudyofmodernacousticsthroughthestudyofvibrations

• 1668-Isaacnewtonstudiedthespeedofsoundthroughair

• 1842-ChristianJohannDopplerproposedthe‘Doppler’effect

• 1880-Paul-JacquesCurieandPierreCuriediscoverpiezoelectricity

• 1914-1918-PaulLangevinandConstantinChilowskydiscoveredawaytousethepropertyof

echoingsoundwavestodetectunderwaterobjects(SONAR=SoundNavigationandRanging)

• 1940s-KarlDussikisapsychiatristandneurologistwhodetectedintracraniallesionsand

discoveredone-dimensionalA-modedisplay

- GeorgeLudwig,JohnWildandWilliamFry

• 1950s-DouglassHowryandJosephHolmesproducea2-Dcompoundscannerandthenthe

bistabledisplay(2-Dimagedisplayedinblackandwhite)

- In1959,theultrasonicinstitutebeganinSydneyAustralia,thankstoGeorgeKossoff,DrWilliam

GarrettandDavidRobinson

- DopplerUltrasoundresearchbeganinlate1950sbyDonaldBaker

• 1965-WalterKrauseandRichardSoldnerdevelopedthefirstreal-timescannerinGermany.Itwas

manufacturedas‘Vidoson’bySiemensandusedrotatingtransducers

• 1969-GreyscalingwasdevelopedattheultrasonicinstitutebyKossoffandhisteam

• 1975-“Octoson”wasdevelopedbytheUltrasonicInstituteinSydney.Itisarapidmulti-transducer

water-bathscannerthatproducedhigh-resolutioncompoundscansatarateof1scanpersecond

• 1980s-Transducerdesignimprovedwithresearch

• 1900s-Harmonicimagingimprovedvisualisationofdifferenttypesoftissue

• 2000s-Introductionof3D/4Dultrasound,contrastenhancedultrasound,molecularimaging,fusion

imagingandelastography

3. ULTRASOUNDEDUCATIONTheoriginsofformalultrasoundtraining:

• In1969,theAustralasianSocietyforUltrasoundinMedicine(ASUM)beganfromUltrasonic

Institute(UI)staffandclinicalcollaborators

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• ASUMintroduced–1976–theDiplomaofDiagnosticUltrasound(DDU)establishedfordoctorsand

in1979–theDiplomaofMedicalUltrasonography(DMU)establishedforpara-medicalpersons

(obstetric/vascular/cardiac/general,stillavailabletoday)

Postgraduateultrasoundeducation:

• 1980–RMITestablishedGraduateDiplomainUltrasonography(nolongerofferedhere)

• 1984–pressurefromwithinQLDtodevelopultrasoundcourse–QUTattemptstoaccreditcourse–

notaccomplisheduntil:

• 1989–QUTestablishesMastersofAppliedScience(MedicalUltrasound)withoptoutGraduate

Diploma

• 1992–AustralianSonographersAssociation(ASA)establishedinMelbourne

• 1994–AustralasianSonographersAccreditationRegistry(ASAR)establishedbyASUM,AIR,ASAand

theuniversitiesinvolvedinsonographereducationatthetime

• 1995–firstprivatepracticalultrasoundtraininginstitute,theAustralianInstituteofUltrasound

(AIU)setuponGoldCoast

• Today–thefollowinguniversitiesofferaccreditedpostgraduatequalificationsinAustralia:

CQUniversity,QueenslandUniversityofTechnology,UniversityofSouthAustralia,Monash

University,CurtinUniversityofTechnology,CharlesSturtUniversity,WesternSydneyUniversity.

Andotherorganisationstoofferaccreditedprograms:ASUM(general,cardiac,vascular,obstetric)

andAIHE(general)

InAustralia,thepracticeofsonographyrequires:

- Successfulcompletionofanaccreditedprogram

- RegistrationwithAustralianSonographerAccreditationRegistry(ASAR)- Recommendedmembershipwithoneofthefollowingprofessionsbodies:Australasian

SonographersAssociation(ASA)ORAustralasianSocietyforUltrasoundinMedicine(ASUM)

- ASARprovidesaccreditationofprogramsandsonographers.Overseasqualificationsassessedby

AIR

NationalRegistrationandRegulation

• Registration–ahealthpractitionersnameisonaregisterthatthegeneralpubliccanaccess

• Regulation–practitionersabidebynationallawsregardingtheirpractice

• InAustralia–AHPRA(AustralianHealthPractitionerRegulationAgency)assistsinregulationof

medicalimagingpractitionersexceptsonographers• TheAHPRAisgovernedbytheHealthPractitionerRegulationNationalLaw.Theprimaryaimisto

protectthehealthandsafetyofthegeneralpublic• MRPBA(MedicalRadiationPracticeBoardofAustralia)arepartofAHPRA–primarilyradiographers

andnuclearmedicinetechnologists

SonographerRegulation

- SonographersarenotpartoftheMRPBAorAHPRA

- Sonographyisaself-regulatingprofessionintermsofentrylevelrequirements,educationand

continuingprofessionaldevelopment

- ASARaccreditssonographersandeducationalinstitutions- TomaintainaccreditationsonographersmustundertakeCPD

- Thereisnomandatoryreportingofsonographers

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4. THEAUSTRALIANHEALTHCARESYSTEM

TheAustralianhealthsystemisworld-classinbothitseffectivenessandefficiency:Australiaconsistentlyranksinthebestperforminggroupofcountriesforhealthylifeexpectancyandhealthexpenditureperperson(WorldHealthOrganisation2003)

• Australia’spopulationasat11thMarch2017wasestimatedtobeover24millionpeople(24386

711)–increasingby1personevery1minand24seconds

• TheAustralianpopulationhasagenerallygoodhealthstatus,withanaveragelifeexpectancyat

birthof8.14years(79.2formenand83.7forwomen),oneofthehighestintheworld

• Therearesomegroupswithpoorhealthstatus,notablyAboriginalandTorresStraitIslander

people;otherwisethepatternofdiseaseislikethatofotherdevelopedcountries

• Australia’srobustprivatehealthsectoriscomplementedbyauniversalpublichealthsystemcalled

Medicare

• Wehavethreetiersofgovernment:

- FederalGovernment–Canberrabased

- StateGovernment–capitalcitybased

- LocalGovernment–centrallybasedintheirowncityorshire

FederalGovernmentResponsibilities

• Medicare–nationalschemeprovidingfreeorsubsidisedaccesstomedicalfacilities

• PharmaceuticalBenefitsScheme(PBS)–subsidisesuniversalaccesstothousandsofprescription

medicines

• Rebatesforprivatehealthinsurancepremiums

• Veteranshealthcare

• Researchfunding

• Collectingtaxestopayfortheseschemes

StateGovernmentResponsibilities

• Publichospitals,theirmanagementandadministration

• Breastscreenandimmunisation,deliverythereof

• Fundingandmanagementofcommunityhealthschemes,publicdentalclinics,ambulanceservices,

patienttransportsubsidyschemeetc.

LocalGovernmentResponsibilities

• Community-basedhealthandhomecareservicese.g.localwomen’shealthclinicsincludingpap

smearclinics,farmer’shealthclinics,vaccinationclinics,homecareforthehomebound

• Environmentalhealthe.g.sanitationservices

Issueswiththe3-tiergovernmentsystem

• Bickeringanddisputesoverfunding,alongwithcost-shiftingoccurregularly,especiallybetween

federalandstategovernmentsofdifferentpoliticalpersuasionse.g.LiberalFederalgovernmentvs

StateLabourgovernment

• Duplicationofservices/waste

Healthcaresystemtiers

• Primarycare:firstlevelofcontactwiththehealthsysteme.g.GP–noreferralisneeded.Dentists,

indigenoushealthworkers,pharmacists,physiotherapistsandchiropractorsfallunderthiscategory

• Secondarycare:referralfromprimarycaregivere.g.referralfromGPtoseeaspecialist.

Sonographers,echocardiographers,radiographers,radiologists,cardiologists,obstetricians,

urologistsandpaediatriciansfallunderthiscategory

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• Tertiarycare:typically,hospital–publicorprivate

Medicare

• Universalhealthcaresystemintroducedin1984

• Medicareisthefederalgovernmenthealthinsurancesystemmanagedbythe“departmentof

healthandaging”

• TheprincipalaimofMedicareistomakehealthcareaffordableandaccessibleforallAustralians

throughfreeofsubsidedhealthcare

• TheMedicareBenefitsSchedule(MBS)listsallservicesthatarecoveredunderMedicareinsurance

scheme

• ThePharmaceuticalBenefitsScheme(PBS)providessubsidisedfundingfornecessary

pharmaceuticals

• ReciprocalhealthcareagreementsenableAustralianstoreceivefreeessentialmedicaltreatment

whilstoverseasincertaincountries

• 3mainobjectives:fundmedicalservices,fundpharmaceuticalbenefitsandfundpublichospital

care

MedicareLevy

• Startedin1984

• Providesapproximately1/3ofMedicarefunding(remaindercomesfromgeneraltaxes)

• 2%oftaxableincomepaidbyindividualsearningaboveacertainthreshold

MedicareSurcharge

• AnadditionalsurchargeinadditiontotheMedicareLevythathighearningindividualspaythatdo

nothaveanappropriatelevelofprivatehealthcover

PharmaceuticalBenefitsScheme

• Startedin1948

• ThePBSisaschemethatsubsidisesthecostofmedicineforarangeofmedicalconditions

• ThePBSschedulelistsallthemedicinesavailabletopatientsatagovernmentsubsidisedprice

• AllindividualsthatholdacurrentMedicarecardareeligibleforPBS

• Co-paymentof$38.30formostPBSmedicines

• Patientsafetynetof$1,475.70perfamilyperannum

PrivateHealthInsurance

• StronglyencouragedbytheAustraliangovernment

• GovernmentoffersarebateforMedicarecardholderswhotakeoutprivatehealthinsurance

• Benefits:providesshorterwaitingtimes,morephysician/hospitalchoice,fundspartancillary

serviceslikedentistry,physiotherapy

MedicareandDiagnosticImaging

• Rebatesareprovidedforcertaindiagnosticimagingservices,butonlyto:practicesaccredited

undertheDiagnosticImagingAccreditationScheme(DIAS)

• DIASdevelopedtoensuresafetyandqualitystandardsfordiagnosticimagingpractices

• MRIunitsmustberegisteredforpatientstoreceiverebates

• UltrasoundinMBS:

- General:Group1Subgroup1Itemnumber55005-55855

- Echocardiography:Group1Subgroup2Itemnumber55113–

NHMRC

• NationalHealthandMedicalResearchCouncil

• Establishedin1926

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• Supportshealthandmedicalrelatedresearch

• Provideshealthadvicetohealthprofessionalsandgovernments,aswellasthegeneralcommunity

• Providesadviceonethicalbehaviour

5. MEDICALTERMINOLOGY

Themainsourcesofmedicalterminologyaredrawnfrommanylanguages.Greektermsareusedmainlyin

clinicalterminologyandLatintermsareusedmainlyinanatomicalterminology.

GreekoriginsofMedicalTerminology

• Greekswerefoundersofrationalmedicineinabout5thcenturyBC

• HippocraticSchool,andlaterGalenformulatedthetheorieswhichdominatedmedicineupuntil

beginning18thcentury

• Hippocraticsfirsttodescribediseasebasedonobservation

• DiagnosisandsurgerytermsaremainlyGreekinorigin

LatinOriginsofMedicalTerminology

• Latinwastheoriginaluniversallanguageofthewesternworld,andwasthelanguageofscienceup

tothebeginningofthe18thcentury.AllmedicaltextswerethereforewritteninLatin

• AndreasVesalius–Dehumanicorporisfabrica

• AnatomicaltermsarepredominantlyLatininorigin

ComponentsofMedicalWords

• Mostmedicalwordshavethreecomponents:prefix,rootandsuffix

• Root=oftenequalsanelementofanatomy

• Asuffixorprefixareaddedtomodifytherootwordandaddadditionalmeaning

• E.g.pericarditis:peri–around,card–heart,itis–inflammation

UltrasoundTerminology

• Echogenic–toproduceechoes.Structureswhicharemoreechogenicappear‘brighter’

• Hyperechoic(comparativeterm)–areawithincreasedechoes(appears‘brighter’onimage)

• Hypoechoic(comparativeterm)–areawithdecreasedechoes(appears‘darker’onimage)

• Isoechoic(comparativeterm)–areawithasimilarlevelofechoreturnonimage(similar

echogenicity)

• Anechoic/sonolucent–areawithnointernalechoes(appearsblackonimage)

• Homogenous–areawhichcontainsechoesofauniformcomposition

• Heterogeneous–areawhichcontainsechoesofvaryingcomposition

• Echotexture–descriptionoftheechopatternwithinastructuree.g.Homogeneous,echogenic

• Acousticwindow–anareaofthebodywhichisfreefromgasorbone,whichultrasoundcaneasily

passthrough.Theanatomicalstructuresdeeptothis‘window’canbemoreoptimallyevaluated.

Weusetheurinarybladderasanacousticwindowtoimagetheuterus.Weusetheliverasan

acousticwindowtoimagethekidney

• Attenuation–ultrasoundlosesenergyasittravelsthroughtissue.Fivemainprocessesof

attenuation:absorption,reflection,scattering,refractionanddivergence

• Artefacts–structureinanultrasoundimagewhichdoesnotcorrespondtoanactualstructure

withinthebody.Structureswhichareseeninanimagebutarenotactuallypresent,orstructures

whicharepresentandshouldbeseeninanimagebutarenot.Theyareanapparentechoforwhich

thedistance,directionoramplitudeoftheechodonotcorrespondtoarealtarget

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• Posteriorenhancement–anartefactduetoanover-amplificationofechoesdeeptoanareaoflow

attenuation,suchasafluid-filledarea

• Posteriorshadowing–anartefactcausedbyanareaoflowamplitudeofechoesdeeptoahighly

attenuatingstructure,suchasbone

• Adescriptionoftheouteredge/surfaceofananatomicalstructuremaybedescribedas:

encapsulated,welldefined/poorlydefined,lobulated/smooth/speculated,thickwalled/thinwalled

• PosteriorShadowing

• Cystic–usedtodescribeafluid-filledstructure.Doesnotcontaininternalechoesandexhibits

posteriorenhancement

Welldefined Poorlydefined Lobulated SpiculatedSmooth

Thick-walled Thin-walled Hyperechoic Hypoechoic Isoechoic

Anechoic Homogenous Heterogeneous AcousticWindow Posteriorenhancement

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• Loculated–fluidcollectionswhichareseparatedintocompartmentsbyseptations

• Septations–divisionswithinastructure.Variableappearancese.g.thick,thin,vascular

6. ULTRASOUNDSCANPLANES

TransducerOrientation

• Thinkabout:pathofinsonatingsoundandechoandnotchindicatorandtransducer

• Scanningplane:transducerorientationtoanatomicplaneoforgan

UltrasoundScanPlanes

• Longitudinal‘long’–thelongestlengthofthestructurebeingexamined(sagittalorcoronal)

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• Transverse/Axialplaneofstructurebeingexamined(90degreestoLong)

Longitudinal:Sagittalplanes–transducernotchalwaystowardspatientheadinsagittalplanes

Longitudinal:Coronalplanes–transducernotchalwaystowardspatientsheadincoronalplanes

Transverseplanesanteriorandposteriorsurfaces–transducernotchalwaystowardsyouintransverse

planes

Transverseplanesrightorleftsurfaces–transducernotchalwaystowardsyouintransverseplanes