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The MIA Victoria Imaging Update

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					The MIA Victoria Imaging Update
                                                                                                                                           UPDATE
                                                                                                                                           The MIA Victoria Imaging Update • Feb 2008




                                 detect CAD aids in the                have coronary artery disease as a potential cause of their
                                                                                                                                           Keeping “Abreast” of the Triple Test
                                 management of risk factor             symptoms. After an individual has undergone coronary
                                 modification, medical therapy         stenting or coronary artery by-pass graft, further symptoms                                                                             Breast imaging
                                 or intervention.                      may occur, and the cardiac CT may be able to pin point                                    Darren Lockie is an MIA Victoria              There are two distinct groups of patients:
                                                                       whether there is recurrent narrowing within the stent or                                  radiologist with a strong interest in
                                 Who benefits from                     by-pass graft. It has been estimated that up to 50% of bypass                             breast imaging, and has had a long            1. The “screening” group (i.e. normal population without
                                 Cardiac CT Scanning?                  grafts are occluded (often silently) within 10 years of bypass                            association with Breastscreen                    symptoms or signs).
                                                                       surgery. Patients, who are unable to have a stress test,                                  Victoria. Darren is currently consultant      2. The “diagnostic” group (i.e. there are signs and/or
                                 Individuals at high risk for
                                                                       or have an equivocal result, may undergo cardiac CT to                                    to Regional Imaging on digital                   symptoms. For example: pain, tenderness, nipple
Marked narrowing of mid-RCA      premature heart disease,
                                                                       clarify their heart status.                                                               mammography, chief radiologist                   discharge, thickening or palpable lump).
detected on MSCT                 people who experienced chest
                                                                                                                                                                 of Maroondah and Gippsland
                                 pains or shortness of breath                                                                                                                                                                                         The radiological approach
                                 of indeterminate cause, or
                                                                       What are the contraindications                                      Darren Lockie         Breastscreen services and consultant           A.
                                                                       to the procedure?                                                   radiologist to Breastscreen Victoria on their digital                                                      is usually different for both
                                 people who experience                                                                                                                                                                                                groups, in that if the
                                                                       People with irregular heart beats (like atrial fibrillation or      mammography implementation and appraisal project.
                                 recurrent chest pains after
                                                                       frequent ectopic beats), who are unable to hold their breath                                                                                                                   “screening” mammogram
                                 prior coronary stents or
                                                                       for 15 seconds or more, cannot stay still or have kidney                                                                                                                       is normal, ultrasound would
                                 by-pass surgery are the                                                                                   Breast screening programs utilize the “triple test” in
                                                                       impairment (contraindication to contrast), morbid obesity                                                                                                                      not be performed. However,
                                 common indications for this                                                                               assessing the significance of screening detected
                                                                       (poor quality pictures) or allergy to contrast are not likely                                                                                                                  in the “diagnostic” situation
                                 procedure. Premature heart                                                                                abnormalities. The triple test approach is equally helpful in
                                 disease occurs in individuals         to benefit from the procedure. Additionally, individuals                                                                                                                       (particularly if there is
                                                                                                                                           the diagnostic context where a patient, (either male or
                                 with two or more risk factors         with known extensive coronary calcification (due to prior           female) has a breast related symptom or sign.                       A. Mammogram of simple cyst.
                                                                                                                                                                                                                                                      localised pain or palpable
Marked narrowing of mid-RCA      of diabetes, hypertension,            evaluations or previous coronary angiography) are also not                                                                                                                     lump) even if the mammo-
detected on MSCT                                                                                                                                                                                                                                      gram is normal, ultrasound
                                 hypercholesterolaemia,                suitable, as the calcium will obstruct visualisation of the         Triple test                                                          B.
                                 smoking and those with a              coronary lumen.                                                     The triple test is a combination of:                                                                       would be used as a
                                 family history of premature                                                                                                                                                                                          complementary modality.
                                                                       Summary                                                             1. Clinical history and examination.
                                 heart disease.                                                                                                                                                                                                       Ultrasound is especially
                                                                       Multi-slice computer tomography is emerging as a very               2. Imaging results:                                                                                        helpful in young women
                                 How long does the                     accurate imaging tool to diagnose symptomatic heart disease            – most commonly mammography and ultrasound.                                                             who usually have
                                 procedure take?                       in the community. Expect this revolutionary test to play a             – occasionally MRI and PET.                                                                             mammographically dense
                                 Patients typically take beta          more important role in assessing the health of individuals
                                                                                                                                           3. Pathology:                                                                                              breast tissue, and older
                                 blockers to slow the heart rate       particularly with respect to heart disease in the future.                                                                               B. Ultrasound of simple cyst.
                                                                                                                                              – fine needle aspiration for cytology (FNAC).                                                           women with dense tissue,
                                 and come in a calm and                MIA Victoria at Peninsula Private Hospital, Frankston,                 – needle core biopsy for histology.                                                                     often secondary to HRT,
                                 relaxed manner. After an                                                                                                                                                       C.
Marked narrowing of mid-RCA on                                         in collaboration with a Cardiologist and Radiologist, has              – open surgical excision biopsy.                                                                        as the detectability of
coronary angiogram               intravenous drip is inserted,         successfully implemented cardiac CT scanning, and since                                                                                                                        lesions (even large lesions)
                                 GTN spray is given, the patients      February 2007, have examined over 350 patients.                     Why the triple test                                                                                        with mammography is made
                                 are asked to hold their breath                                                                            The triple test has a sensitivity of 99.6% compared with:
                                                                       Dr Andrew Watson, MBBS, FRANZCR, Member ANZAPNM                                                                                                                                more difficult by the dense
                                 for 15 seconds while contrast                                                                             – clinical only, sensitivity 50-85%.
                                                                       Clinical Director – Peninsula Private Hospital Radiology                                                                                                                       breast tissue.
                                 is injected and scanning                                                                                  – imaging only, sensitivity 90%.
                                 occurs. The whole procedure           525 McClelland Drive, Frankston, Vic 3199                                                                                                                                      Breast implants are usually
                                                                                                                                           – pathology only, sensitivity 91%.
                                 takes 30-60 minutes and               Dr Gregory Szto, MBBS (Hons), FRACP, FCSANZ, FSCAI, SCCT (Member)                                                                                                              difficult to assess with
                                 patients usually return to their                                                                          The triple test is positive in 99.6% of breast cancers, and is      C. Ultrasound guided cyst aspiration   mammography due to the
                                                                       Director of Cardiology – Peninsula Private Hospital
                                 usual activities fairly soon after.                                                                       defined as positive if any of the components are positive.          (needle tip in centre of cyst).
                                                                                                                                                                                                                                                      overlap of glandular tissue
                                                                       525 McClelland Drive, Frankston, Vic 3199
                                 The scan is then processed and                                                                            If the triple test is negative (i.e. all components are negative)                                          by the implant. Ultrasound
                                                                                                                                                                                                                D.
                                 the results sent to the patient’s                                                                         then the risk of missing cancer is less than 1%.                                                           is very helpful in assessing
RCA post stent insertion         referring doctor.                                                                                                                                                                                                    both glandular tissue and
                                                                                                                                                           ACCURACY OF TRIPLE TEST                                                                    the implant. Digital
What are the indications for the procedure?                                                                                                                                Sensitivity                                                                mammography is less
Individuals may want to check whether they are at risk of                                                                                    Triple Test                      99.6%                                                                   effected in these situations
silent heart disease, either because of multiple risk factors                                                                                Clinical                          85%                                                                    and may have a specific
or there is a family history of premature heart disease.                                                                                                                                                                                              role in the future in imaging
                                                                                                                                             Imaging                           90%
People who are experiencing chest pains or shortness of                       Level 1, 1355 High Street, Malvern, Victoria 3144                                                                                D. Image showing complete drainage
                                                                                                                                                                                                                                                      implants and women with
breath or undue tiredness may want to check whether they                         Tel: (03) 9804 6100 Fax: (03) 9821 0787                     Pathology                         91%                             of cyst.                               dense breast tissue.


MIA Victoria is a member of the I-MED Network                                                                    www.miavictoria.com.au    MIA Victoria is a member of the I-MED Network                                                                   www.miavictoria.com.au
The MIA Victoria Imaging Update                                                                                                                                                                                                              Medical Imaging Updates


Accurate, detailed clinical notes on the referral are very                                                              A breast specialist is
important in alerting the radiologist and technologist to the
                                                                                H.
                                                                                                                        also the best person to       Detection of Coronary Artery Disease With Multi-Slice
possible need to do further work-up views and ultrasound.
Using the “clock face” is an easy, quick way of localising the
                                                                                                                        correlate the components
                                                                                                                        of the triple test,
                                                                                                                                                      Cardiac CT Scanner By Dr Andrew Watson (Radiologist, MIA Victoria) & Dr Gregory Szto
problem. An example of a referral could be – 2cm cyst at left                                                           especially if there is
2 o’clock position, 5cm from nipple. This allows a tailored                                                             discordance.
approach and can usually answer the clinical question.
                                                                                                                        With discordant results,
Imaging guided breast procedures                                                                                        it is important to evaluate
Breast lesions are amenable to percutaneous sampling,                          H. Coned mammogram of typical            the relative significance
                                                                               invasive carcinoma.
either using fine needle aspiration for cytology, or core                                                               of each component,
biopsy for histology, as long as they are visible on either the                  I.                                     discounting results that
mammogram or ultrasound.                                                                                                do not fit the overall
                                                                                                                        impression.
Like most procedures, breast sampling is operator dependent
and its contribution towards providing a meaningful                                                                     For example, where
pathological diagnosis depends on accurate lesion targeting                                                             clinical and imaging
and sampling. Small lesions can be difficult to localise, and                                                           investigation suggest a
adequate samples of the “lesion” are very dependant on the                                                              cancer, but fine needle
expertise of the operator.                                                                                              aspiration shows no
The other important aspect is the correlation of clinical,                     I. Ultrasound of same lesion as above.   malignancy, then a
imaging and pathological results, especially if there is discord                 J.                                     core biopsy should be         Coronary artery disease (CAD) is a major cause of death in                                            coronary arteries and cardiac
between the clinical/imaging appearance, and pathology.                                                                 performed as the FNA is       Western societies. Each day, 140 Australians die from the                                             chambers. This is accomp-
A breast specialist is the most appropriate person to assess                                                            likely to have been wrong.    effects of heart disease. Coronary artery disease results                                             lished with ECG gating. Data
the significance and implications of discordant results.                                                                                              from the restriction of coronary artery blood flow. Acute                                             acquired requires processing
Who should request imaging guided biopsy?                                                                                                             occlusion results in myocardial infarction, sometimes with                                            with dedicated computer
                                                                                                                                                      fatal consequences.                                                                                   workstations. This allows
  E.                                         Apart from simple cyst                                                                                                                                                                                         assessment of the coronary
                                             aspiration which is                                                                                      CAD often progresses in a silent and gradual manner. As
                                                                                                                                                                                                                                                            artery luminal diameter with
                                             performed using a fine                                                                                   plaques progress, patients may remain asymptomatic until
                                                                               J. Ultrasound guided core biopsy                                                                                                                                             objective measurements of
                                             needle, the choice                                                                                       plaque burden is severe. When critical narrowing is achieved,
                                                                               showing satisfactory needle position.                                                                                                                                        any coronary artery
                                             between using FNA                                                                                        patients will present with typical exertional angina.
                                                                                                                                                                                                                                                            narrowing. Plaque assessment
                                             cytology or core biopsy           A suggested clinical flow chart could be:                              However, symptoms can be subtle and atypical, making
                                                                                                                                                                                                                       CT image of Right Coronary Artery.   is also possible. Plaques can
                                             histology for solid lesions                                                                              assessment difficult. Symptoms may include tiredness,
                                                                                                                                                                                                                                                            be assessed as non-calcified,
                                             is not an easy one and                            General practitioner assessment                        lethargy and dyspnoea on exertion. Plaques can become
                                                                                                                                                                                                                                                            calcified or mixed. Cine
                                             is influenced by clinical                                                                                unstable, exacerbating CAD with reduced coronary blood
E. Ultrasound of typical fibroadenoma.                                                                                                                                                                                                                      images allow assessment of
                                             factors including age,                                                                                   supply leading to myocardial dysfunction and death. When
                                                                                                                                                                                                                                                            left ventricular contraction,
                                             history, examination,                                                                                    chronic, this progresses to chronic heart failure.
  F.                                                                                             Initial imaging ordered by GP:                                                                                                                             regional wall motion and
                                             satisfactory samples,                                                                                    Acute occlusion of unstable plaques can be hastened by                                                thickening.
                                                                                                 mammography and ultrasound
                                             (more difficult with FNA)                                                                                factors such as smoking, diabetes, high blood pressure, and
                                             and pathologist expertise,                                                                                                                                                                                  A coronary artery calcium
                                                                                                                                                      high cholesterol. Sudden death may be the first presentation                                       score is routinely performed.
                                             especially with cytology.                                                                                of CAD. If acute occlusion is survived, the occlusion can be
                                                                                 Specialist assessment of clinical and imaging findings                                                                                                                  The higher the calcium score
                                             Fine needle aspiration                                                                                   treated with fibrinolysis or urgent percutaneous intervention                                      the more likely the individual
                          E.                 cytology can be performed    I.                                                                          with angioplasty and/or stents.                                  Tree Volume Rendered (VR) view of is likely to have CAD. Coronary
                                             without a prior clinical                                                                                                                                                  Coronary Arteries from MSCT
                                                                                                                                                      High-risk individuals with atypical symptoms are usually                                           artery calcium score is one of
 G.                                          examination by a breast                 Imaging guided biopsy ordered by specialist:                                                                                      the most accurate predictors of future cardiovascular events.
                                                                                                                                                      investigated with ECG stress test, thallium/sestamibi
                                             specialist, as there is little        mammographic (stereotactic) or ultrasound guided                   nuclear stress test or stress echocardiography.
                                             risk of haematoma, but                                                                                                                                                    Why Cardiac CT?
                                             this is not ideal.                                                                                       Recently a new imaging technique has become available
                                                                                                                                                                                                                       MSCT allows visualisation of the coronary arteries down to
                                                                                                                                                      with multi-slice computer tomography (MSCT).
                                             However, core biopsy                              Specialist’s correlation of results                                                                                     1.5mm in diameter. It can provide information on coronary
                                             requires prior breast                                                                                    MIA Victoria has recently introduced 64-slice CT scanners        artery narrowing and plaque composition in a relatively
                                             examination by a breast                                                                                  into practices. This allows for a relatively non-invasive        non-invasive test. The true strength of cardiac CT is the high
                                             specialist, as there is a         Summary                                                                investigation involving an IV contrast injection via an ante-    negative predictive value of 99%. This means that if a MSCT
F. & G. Image guided core biopsy showing     fair chance the biopsy            By utilising the triple test approach to breast lesions,               cubital fossa vein with rapid thin multi-slice scanning. These   reports no coronary artery disease, 99% of the time there is
needle within lesion in sagittal and         procedure will alter the
transverse scans (needle position confirms
                                                                               in conjunction with specialist correlation, we are able to             new MSCT scanners have the advantage of high temporal            no disease at all (it is highly accurate in excluding coronary
proof of accurate and adequate sampling).    clinical findings.                provide our patients with “best practice”.                             and spatial resolution allowing the imaging of small, moving     artery disease). The ability of cardiac CT to non-invasively


MIA Victoria is a member of the I-MED Network                                                                                www.miavictoria.com.au   MIA Victoria is a member of the I-MED Network                                                                 www.miavictoria.com.au

				
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