18-20 Week Screening Pregnancy Ultrasound
What are the generally accepted indications for 18-20 week screening pregnancy ultrasound? Ultrasound at 18–20 weeks of gestation has become a routine screening procedure in pregnancy, and is ideal for assessing gestational age, foetal number, foetal viability and placental location, and if medically required, foetal gender. It is also valuable in detecting abnormalities in amniotic... View ArticleAmniocentesis
What are the prerequisites for having an amniocentesis done? The following women can be referred for amniocentesis: over 36 years of age, past history of a child with an abnormality, those who have had an abnormality in their foetus or unborn baby identified on an ultrasound scan, personal or family history of a chromosomal abnormality... View ArticleAngiography
What are the common indications for angiography? This InsideRadiology item deals with the large number of treatment procedures that use catheter angiography requiring the ‘direct’ injection of contrast into a diseased artery or vein. This is in contrast to diagnostic angiography (which is obtained by ‘indirect’ imaging techniques) such as CT, MRI and duplex ultrasound.... View ArticleArthrogram
What is an arthrogram? An arthrogram is an image of the inside of the joint obtained by arthrography. This is a procedure carried out by inserting a needle into a joint and injecting contrast medium into the joint cavity using imaging to guide the needle into its correct anatomical position. Guidance may be obtained using... View ArticleBone Mineral Density Scan (Bone Densitometry or DXA Scan)
What are the generally accepted indications for a BMD scan? The following indicate an increased risk for bone loss (osteoporosis) and might require BMD assessment to confirm osteoporosis. Although BMD scanning can be carried out for any of these risk factors, only some satisfy Medicare re batable indications, as specified in the MBS handbook. These... View ArticleBreast MRI
What are the prerequisites for having a breast MRI done? Ideally MRI should be scheduled for days 6-12 of the menstrual cycle unless there is a clinical urgency to have the procedure performed as soon as possible (e.g. known breast cancer awaiting treatment). Ideally, breast MRI should not be performed in women who are taking... View ArticleChorionic Villous Sampling
What are the generally accepted indications for chorionic villous sampling? Chorionic villous sampling (CVS) is usually carried out between 11 and 14 weeks of gestation (but can be carried out up until full term in selected cases), and involves either transabdominal or transcervical aspiration or biopsy of placental villi. Previously, only amniocentesis was available for... View ArticleComputed Tomography (CT)
What is computed tomography? Computed Tomography (CT) is a high resolution technique using X-ray technology to generate images of any area of the body. Patients are placed on a moveable X-ray table which then enters the CT gantry. Depending on the equipment used, one or sometimes two Xray tubes rotate around the patient at high... View ArticleCoronary Artery Calcium Scoring
What is a coronary artery calcium scoring? Coronary artery scoring is a CT scanning technique for identifying and quantifying calcium deposits in the coronary arteries reflecting underlying atherosclerosis. It relies on the ability of the CT scanner to detect small areas of calcium within atheromatous plaques. As there is no intravenous contrast medium given to... View ArticleCT Colonography
What are the generally accepted indications for a CT colonography? Screening for bowel cancer in people who are considered to have no increased risk of developing bowel cancer, failed or incomplete conventional colonoscopy and, when colonoscopy is relatively contraindicated because of significant medical conditions. Note: Individuals at higher risk of colon cancer because of positive... View ArticleCT Coronary Angiography (CTCA)
What is a computer tomography coronary angiography (CTCA)? Angiography is the X-ray imaging of blood vessels using X-ray contrast agents injected into the bloodstream. CTCA uses computed tomography (CT) scanning to take images (angiograms) of the coronary arteries. It requires the use of rapid CT scanning techniques, and can only be carried out in centers... View ArticleDiagnostic Mammography
What are the prerequisites for having diagnostic mammography done? Diagnostic mammography is performed in symptomatic patients, that is patients who have signs or symptoms of breast cancer such as a palpable lump, nipple discharge, skin changes etc. What are the absolute contraindications for diagnostic mammography? There are no absolute contraindications for diagnostic mammography. What are... View ArticleDual Energy CT Scan
What is a dual energy CT? Dual energy CT scans are a newer form of CT scanning that use separate X-ray energies to make images. Images can be generated: by the simultaneous use of two X-ray tubes (‘dual source’); by using an X-ray detector with separate layers to detect two different energy ranges (‘dual layer’);... View ArticleFoetal MRI
What is a breast MRI? What are the prerequisites for having a foetal MRI done? Foetal MRI may complement ultrasound examination when detailed evaluation is required of intracranial and intrathoracic structures. It is also valuable when planning ante- or early postnatal surgical foetal intervention (e.g. in spina bifida, congenital diaphragmatic hernias, neck masses obstructing the... View ArticleMagnetic Resonance Imaging (MRI)
What are the generally accepted indications for magnetic resonance imaging (MRI)? Magnetic resonance imaging is increasingly being used for diagnosis and follow up. The wide range of indications can be grouped under: Brain – indications include stroke, temporal lobe epilepsy, infection, inflammation, tumour, multiple sclerosis (MS), dementia, post-trauma, metabolic disorders, congenital malformations, internal auditory canal... View ArticleMRI Heart (Cardiac MRI)
What is cardiac MRI? Cardiovascular magnetic resonance (CMR) is an advanced form of magnetic resonance imaging utilising electrocardiogram gating to avoid cardiac motion blurring. Its main use is in assessment of anatomy, function and viability of the heart, but it is also useful in detecting ischaemia and infarction, and in assessing congenital heart disease, the... View ArticleMyelogram
What are the generally accepted indications for a myelogram? Myelography is becoming less common with the introduction of high quality magnetic resonance imaging (MRI). However, two indications remain for a myelogram – In patients who require imaging as a result of a clinical diagnosis of nerve root, thecal sac or spinal cord compression from disc,... View ArticleNuchal Translucency Scan
What are the generally accepted indications for first trimester screening (nuchal translucency scan)? All women who are pregnant are recommended to have a screening ultrasound at around 11 weeks gestation. In addition to screening for foetal genetic abnormalities (e.g. Down syndrome), other indications include: confirming viability; dating and confirming due date; assessing early foetal anatomy;... View ArticlePlain Radiograph/X-ray
What is a plain radiograph/X-ray? This is the most simple, cost-effective and readily accessible imaging technique available. It provides excellent imaging details of bones, joints and areas of the body where there is substantial soft tissue differences in X-ray absorption; for example, in the thorax where there is marked X-ray differences between bone, lungs and soft tissues.... View ArticleRadiation Risk of Medical Imaging During Pregnancy
Which radiology tests are absolutely contraindicated during pregnancy? No radiological examination is absolutely contraindicated during pregnancy. As there are no dose limits in the medical use of ionising radiation, the risk of the procedure must be weighed against the risk to the patient and her foetus if she does not have the procedure. Which radiology... View ArticleRadiation Risk of Medical Imaging for Adults and Children
What are the generally accepted indications for a medical imaging procedure? An appropriate imaging procedure is justified if it changes patient management or treatment, or confirms or excludes the presence of disease. The type of imaging procedure, as to whether ionising radiation is involved, will be determined by the presenting clinical problem. For further information... View ArticleSaline Infusion Sonohysterography (SIS)
What are the prerequisites for having a SIS done? There are no prerequisites. It is a good test to assess the endometrium for those patients who have persistent endometrial thickening, suspicion of polyps, and assessment of post menopausal endometrium, patients taking tamoxifen, or those with possible Asherman’s Syndrome. What are the absolute contraindications for a... View ArticleScreening Mammography
What are the benefits of screening mammography? Eight randomized controlled trials dating from the 1970s have shown that mammographic screening for breast cancer reduces the mortality from breast cancer by over 20%. Participation in BreastScreen Australia has been shown by case–controlled studies to be associated with a reduction in mortality from breast cancer of over... View ArticleTransvaginal Ultrasound
What is a transvaginal ultrasound? A transvaginal ultrasound examination involves an ultrasound undertaken through the use of an intravaginal probe. It allows detailed assessment of the uterus (including endometrium), cervix, fallopian tubes and ovaries. It is of particular value when a transabdominal pelvic scan is suboptimal due to an undistended bladder, excess pelvic bowel gas... View ArticleTraumatic Vascular Injury – Head & Neck
What is the incidence of traumatic vascular injury of the head & neck? The incidence of blunt cerebrovascular injury (BCVI) varies depending on the criteria used and the sensitivity of the diagnostic test applied. Those using catheter angiography with fairly liberal criteria such as Biffl et al.1 described an alarming incidence of 1.07% for blunt... View ArticleUltrasound
What is an ultrasound? Ultrasound (US) uses high-frequency sound waves to image soft tissues of the body. The frequency of the sound is less than that used in other clinical areas (e.g. physiotherapy), so it is not associated with local heating effects and is completely safe. US is relatively inexpensive, readily available in all imaging... View ArticleUrethrogram
What are the generally accepted indications for a urethrogram? A urethrogram is a procedure used to show the location and characteristics of a clinically suspected urethral stricture, which is most often a result of trauma, surgery, prolonged catheterisation or radiation therapy. Those men with poor urinary stream, not thought to be a result of prostatomegaly,... View ArticlePage last modified on 16/3/2018.
