Volume 8 Issue 3 - Australasian Society for Ultrasound in Medicine

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POLICIES and STATEMENTSFetal structureThe following list of gestational agesat which various fetal structures maybe visualised is not intended to providea complete list of what shouldbe examined. However, using highresolution equipment (often only witha vaginal transducer) the followingstructures can commonly be seen:9 weeks Head, trunk and limbs10 weeks Some ossification oflong bones, jaw and skull11 weeks Stomach, spine, ossifiedcranium, four chamber heart12 weeks Mid gut herniation nolonger present, kidneys, bladder.Nuchal translucencyThe nuchal translucency measurementis a test to assess the risk of chromosomalabnormality, in particular of trisomy21. The measurement may alsobe abnormal in other fetal anomalies(e.g. some congenital heart disease). Ithas been estimated that first trimesterscreening by a combination of sonographyand material serum testing ofPAPP-A and free βhCG can potentiallyidentify 94% of trisomy 21 fetuseswith a false positive rate of 5% 2 .This study should be performedby adequately trained staff accordingto strict protocol. The outcomesof the test should be audited regularly.The recommendations of theFetal Medicine Foundation/ RoyalAustralian and New Zealand Collegeof Obstetricians and Gynaecologistsshould be noted.It may be performed between thegestational ages of eleven (11) weeksand thirteen (13) weeks plus six (6)days (CRL 45–84 mm). A measurementgreater than 2.5–3 mm is usuallyconsidered to be abnormal but mustbe correlated with gestational age.Reference values have been providedby Nicolaides 3 .The nuchal translucency measurementmay be performed at the requestof the referring Medical Practitioner.Due consideration should be given asto how and who is going to counselthe patient prior to the performance ofa nuchal translucency scan.Each practice should develop awritten protocol on the procedure tobe followed when the measurementis abnormal. This protocol shouldinclude guidelines for the immediatecare of the patient and how the referringdoctor will be informed. Usuallythe referring doctor should be notifiedso that appropriate counseling may begiven and the patient can be referredto a specialised unit where formal riskassessment and counseling processcan be undertaken.Method of measurement1 The nuchal translucency shouldbe measured on a sagittal midlinescan through the fetus.2 The fetus should be in neutral positionand occupy at least 75% of theimage.3 The amnion should be seen separateto the fetal skin line.4 Calipers should be positioned tomeasure the maximum diameter ofthe fluid at the back of the neck.Ovaries, uterus and adnexaEach ovary should be examined.The corpus luteum can vary greatlyin appearance during the first (andearly second) trimesters of pregnancy.Sonographic appearances includea solid, rounded target like lesionor a predominately cystic structure.Peripheral vascularity is usuallydetectable.The size of a corpus luteum is alsovariable, commonly measuring up to3 cm.Larger or unusual masses shouldassessed as in the non pregnantwoman.The uterus should be examined forevidence of a fibroids or uterine developmentaldefects. The uterine positionshould also be noted (anteverted,axial, retroverted).The adnexa should be examinedfor coexistent ectopics and free fluid.References1 Hately, Case and Campbell. Establishingthe death of an embryo by ultrasound.Ultrasound Obstet. Gynecol 1995; 5:353–357.2 Nicolaides KH Am J Obstet Gynecol 2004;191: 45–47.3 From Nicolaides group: Snijders et al..Assessmant of risk of Trisomy 21 bymaternal age and fetal nuchal-translucencythickness.34 ASUM Ultrasound Bulletin 2005 August; 8 (3)
POLICIES and STATEMENTSInterim Statement on the Appropriate Useof Diagnostic Ultrasound Equipment forNon-Medical Entertainment UltrasoundIssued July 2005Background/PreambleSince its introduction to medical practice and the biologicalsciences in the l950s, ultrasound has grown from being asubject of minor curiosity to probably the most widely usedimaging modality throughout the world across dozens ofclinical disciplines.A major initial clinical application was in the disciplineof obstetrics and this has continued through to the currentday where modern diagnostic ultrasound plays a major rolein the clinical management of pregnancy. The use of diagnosticultrasound in pregnancy has been underpinned by alarge volume of research into issues concerning bioeffectsand safety in human tissue. For many years, most of thelearned bodies, worldwide, concerned with imaging andobstetrics, have encouraged the appropriate and safe use ofdiagnostic medical ultrasound equipment.The recent widespread availability of good quality realtime three-dimensional diagnostic ultrasound equipmenthas seen the proliferation of businesses offering ultrasoundexaminations during pregnancy for the purpose of producing‘keep sake’ images of fetuses. This has been most prevalentin the United States where much effort is currently beingdirected toward regulating this phenomenon and restoringthe use of diagnostic medical ultrasound equipment to thearea of medical diagnosis as opposed to entertainment (seewebsites of United States Food and Drug Administration,American Medical Association).Confining the use of diagnostic medical ultrasoundequipment in pregnancy to examinations for the purpose ofproviding medical information useful to the management ofpregnancy is based on the following principles:1 Bioeffects and safetyIt is widely accepted that diagnostic ultrasound, whenused as per guidelines promoted by bodies such as theWorld Federation for Ultrasound in Medical and Biology,the American Institute of Ultrasound in Medicine andthe Australasian Society for Ultrasound in Medicine hasnot been demonstrated to be associated with deleteriouseffects in human tissue. Such statements do not guaranteethe absolute safety of diagnostic ultrasound but ratheremphasise that the long-term effects and the possibilityof subtle effects are not completely known. Prudent use istherefore recommended in order to minimise the chance ofsignificant bioeffects. It should be noted that recommendedpower output levels have been significantly increased inrecent years and much of the safety data relating to the useof diagnostic ultrasound precedes the increased permittedpower outputs for different ultrasound imaging modalities.In terms of exposure to diagnostic ultrasound, all learnedbodies emphasise the ALARA (as low as reasonablyachievable) principle. This principle emphasises that diagnosticmedical ultrasound equipment be used by trainedindividuals to seek relevant diagnostic information with theminimum of exposure, thereby minimising the potential forbioeffects and tissue damage.2 The trivialisation of diagnostic medicaltechnologyTrivialising diagnostic medical technology and the role oftrained technical and medical professional will inevitablyerode the significant relationship between health care providersand patients that currently exists. This will ultimatelybe to the significant detriment of the maintenance of thehigh standard of practice upon which optimum medicaloutcomes are based.3 Potential for misdiagnosisThe potential clearly exists for not detecting significantdiagnoses. Pregnant women may believe that this formof examination is an adequate substitute for a properlyconducted examination involving appropriately trainedsonographers and medical practitioners. A potential problemis also created where the abnormalities are incorrectlydiagnosed or doubt regarding normality is created, therebyproducing significant patient anxiety.4 General noteThere needs to be community discussion regarding theentitlement of a fetus to particular rights, including the rightnot to be exposed to a source of potential harm where nohealth benefit exists.ASUM Ultrasound Bulletin 2005 August; 8 (3)35
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Page 3 and 4: PresidentDr David RogersImmediate P
Page 5 and 6: ientific Meeting of ASUMe r 2005 Ad
Page 7 and 8: ASM 2005 PROFFERED PAPERSFriday 30t
Page 9 and 10: THE EXECUTIVEPresident’s messageD
Page 11 and 12: THE EXECUTIVEAdelaide ASMLooking ah
Page 13 and 14: The DMU (Asia) will deliver high te
Page 15 and 16: THE EXECUTIVEMember ServicesSonogra
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Page 30 and 31: CASE REPORTASUM Ultrasound Bulletin
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Page 34 and 35: Justin O’learyFigure 3 Figure 4co
Page 38 and 39: SOCIAL SCREENINGDraft of a letter s
Page 40 and 41: SOCIAL SCREENINGSonographerMelbourn
Page 42 and 43: THE SOCIETYSUMCertified ISO 9001:20
Page 44 and 45: THE SOCIETYDiploma of Medical Ultra
Page 46 and 47: EDUCATIONExamination dates for 2005
Page 48 and 49: THE SOCIETYThe 2004 Beresford Butte
Page 50 and 51: OBITUARYJames Robert Syme MD, FRACP
Page 52 and 53: THE SOCIETYCorporate Members 2005Au
Page 54 and 55: CALENDARContact Byung Ihn Choi MDCo
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Volume 8 Issue 3 - Australasian Society for Ultrasound in Medicine

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