What is Medical Imaging and Radiation Sciences?

Radiographers are health professionals responsible for creation of medical images using X-rays, Computed Tomography (CT) and Magnetic Resonance Imaging. They play a pivotal role in selecting and implementing the safest and most appropriate examination protocols to answer clinical questions. Radiographers are obliged to act in an ethical and professionally responsible manner and exhibit a high level of communication skills. Radiographers are responsible for the safe use of radiation, using radiation doses as low as practicable to generate quality images. Radiographers work in collaboration with radiologists and other specialist medical practitioners to provide patients with a range of diagnostic examinations.

Plain Radiography

The creation of the plain X-ray begins with the radiographer receiving a request form for a radiographic examination of a particular part of a patient's body. The radiographer assesses the request as well as the patient before conducting the most appropriate imaging methods that will best answer the clinical query. Radiographers must evaluate their images in terms of image quality, radiographic positioning and if it will answer the clinical question. This means radiographers need a high level of knowledge about the science of image formation, radiographic anatomy and pathophysiology. This aspect of radiographic practice is covered in the first three semesters of the course. However, due to the complexity of the human body, illness and disease and the range of patients requiring radiographic services students engage in general radiography throughout the course.


In basic terms, fluoroscopy is “live” imaging which can be performed for a variety of purposes. It can be used to image the digestive tract, the hepato-biliary system and genito-urinary system. In these cases radiographic contrast agents can be introduced into the patient in order to visualize organs that are normally only seen as shadows on a plain X-rays of the abdomen. Mobile fluoroscopic systems also exist, and are used extensively in the operating theatre to guide surgeons in a wide variety of operative procedures from vascular surgery to orthopaedic surgery. Students study the principles and practice of fluoroscopy including digital image processing in second year.

Computed Tomography

Computed tomography (CT) is an integral component of medical imaging. Unlike conventional radiography, in CT the patient lies on a CT bed that moves through into the imaging gantry housing an x-ray tube and an array of specially designed "detectors" which spine around the patient. CT gathers large quantities of data which can be manipulated to reconstruct images in a variety of cross sectional body planes. The image created displays CT numbers which mainly reflect the physical properties of the tissues being investigated. Because of the large range of the CT number scale and the fact that the image is digital, it is possible to manipulate the display to show the underlying soft tissues with enhanced contrast as well as the bony structures. Rapid technological innovation in CT means radiographers today need to be able to recognize and evaluate anatomical structures in a variety of body planes. Study of cross-sectional anatomy and pathology in CT are part of third and fourth year of the course.


Mammography uses dedicated, low-dose X-ray equipment, to obtain images of the breast to assist in the screening and diagnosis of breast cancer and other breast diseases. This is available to women through the Breast screen Program in both Public and Private Imaging Departments. Students in the third year of the course gain an understanding of the imaging process, the anatomy and pathology of the breast and an insight into the highly specialized communication and interpersonal skills required when dealing with patients and the diagnosis of breast disease.

Magnetic Resonance Imaging (MRI)

MRI is a specialised field of medical imaging. It has exceptional soft tissue detail and is not only used in the clinical setting, it is increasingly playing a role in many research investigations. MRI utilises the principle of Nuclear Magnetic Resonance (NMR) as a foundation to produce highly detailed images of the human body. The patient is placed within a powerful magnetic field. Hydrogen atoms in the body (humans are made up mostly of hydrogen and oxygen:) align themselves with a North and South orientation within this magnetic field. A radiofrequency (RF) pulse administered causes the hydrogen atoms to alter the direction of their orientation. The transmitting RF pulse is switched off and the hydrogen atoms begin to return to the alignment they acquired when they were first placed in the magnetic field. Powerful computers perform capture this information and advanced image reconstruction calculations produces an image that can be used for diagnosis.

Digital Subtraction Imaging (DSA)

This is an imaging modality that utilises the technology of digital fluoroscopy and additional equipment and computer systems to image the blood vessels (arteries and veins) of the human body. The images produced serve a diagnostic purpose; that is, diagnosing a pathology or condition. Also, treatment or therapeutic cases can be performed such as stenting (inserting a device into a blood vessel in order to keep it open and allow blood to flow through) or infusion of thrombolytic agents (administering a medication such as Urokinase to help breakdown a recently formed thromus or blood clot). The procedures are performed under sterile conditions and require that the patient be fasted (no food prior to procedure) and the radiologist or cardiologist (the specialist medical practitioner who performs the invasive procedure and subsequently interprets the images) be "gowned" as in an operating theatre. Specialised DVI suites are used to image the blood vessels supplying blood to the heart itself. This modality requires that the radiographer is part of a team approach working closely with other health professionals such as radiologists, cardiologists, nurses and cardiac technicians.

Dual energy X-ray absorptiometry (DEXA)

DEXA is a imaging technique widely used for non-invasive assessment of bone mineral density. This is particularly important in the diagnosis, management, and treatment of osteoporosis. Osteoporosis, within our community, continues to debilitate those with the condition and creates an increased risk of patient debilitation and fracture. DEXA allows for early detection of osteoporosis and acts as a baseline study for studying the effectiveness of preventative management and treatments.

Radiation Therapy


Radiation Therapy is a highly specialised area of medical radiation practice . It is a scientific and clinical profession dedicated to the management of patients with benign and malignant disease. The ionising radiation in its commonest form for treatment is photons (x-rays). The radiation can be used on its own, or in combination with other cancer management strategies such a surgery,  cytotoxic chemotherapy, hormone and immunotherapy treatment. This depends on many factors including the histological diagnosis, how advanced the disease is and the health of the patient.

The radiation can be delivered with one of two intentions radical and palliative. Radical intent is where high doses of radiation (depending on the histological diagnosis) are delivered with the intent to cure, and palliative intent is treatment in order to provide relief from cancer symptoms. One of the main considerations in managing cancer with radiation (as with any other treatment) is maintenance of quality of life for the patient.

The following steps constitute the radiation therapy process:


This is the initial step in the radiotherapy process. At this point the exact position of the tumour is located by utilising diagnostic image acquisition techniques such as plain radiographs, CT, MRI and PET. Simulation of the treatment area may also occur where the treatment ‘set up’ is reproduced and radiographic images of this are acquired and recorded. These images are then interpreted and used to configure individual treatment plans for each patient and also for comparison during treatment itself.

Integration of the above modalities in the localisation of the treatment ensures that even microscopic tumour cells and/or lymph nodes that are positively identified as having tumour present are included.


The tumour/site of original tumour and an area of tissue surrounding it are treated to the highest possible dose. This combined site of tumour and normal cells is known as the Tumour Volume.

Radiation therapy planning utilises sophisticated computer systems to maximise tumour dose and minimise the dose to healthy surrounding tissues. A computer is used to generate a pictorial arrangement of the distribution of the radiation dose that the tumour and surrounding organs will receive. This is imperative because organs such as the spinal cord or lungs can only tolerate minimal doses of radiation before irreparable damage occurs.

For any one particular treatment site the radiation beam can be directed towards the patient from a number of angles (fields) in order to reduce the dose to radiosensitive organs and ensure a high dose region around the tumour volume.


There are a variety of radiation modalities available for treatment. The choice of radiation/particle type (photon, electron, proton, neutron, beta and gamma) and energy depends on a number of factors such as how ‘deep seated’ the tumour is and the nearby radiosensitive structures.

Radiation can be administered externally with machines that work at either Kilovoltage energies (used for treating superficial tumours) or Megavoltage energies (Linear Accelerators which are used to treat deep seated tumours).
Internal radioactive sources are also used to treat tissues and organs such as the tongue, cervix or prostate gland.

Daily treatment has to be both accurate and reproducible. This means that the patient needs to be immobilised in exactly the same position every day. Precise measurements are used to align the radiation beam with the specific area of the body being treated. The treatment area itself can be verified on the treatment machine before, during or after the daily treatment is delivered. These images can then be matched with those from the original planning procedure using sophisticated computer equipment.

Prior to any patients being treated all equipment must go through rigorous quality assurance procedures in order to ensure it is operating safely.

The technology within the field of radiation therapy is constantly developing with the view of achieving optimal conformation of the radiation beam to the tumour volume. Utilisation of Intensity Modulated Radiation Therapy (IMRT) is the closest the technology has got to achieving this.


Ultrasound imaging is performed either by a medical physician or a sonographer. IN order for a sonographer to be registered on the Australian Sonographer Accreditation Registry (ASAR) they must obtain an accredited qualification. This qualification is available through our department though post graduate study in ultrasound. Because of the emphasis upon sonography in the undergraduate degree course, graduates may be eligible for exemption from several of the level one units in the ultrasound course.

Ultrasound imaging uses high frequency ultrasound to construct an image rather than the traditional x-ray. This means that it is a safe, non-invasive means of creating cross sectional images of the human body. It is also a relatively cost-effective means of imaging. Ultrasound is familiar to many because of its role in obstetrics, with many prospective parents experiencing the delight of seeing their developing foetus with this technology. An ultrasound examination is an important medical test which will assist the management of pregnancies, especially complicated pregnancies. Ultrasound however is used with great diversity beyond obstetrics. Ultrasound is used in abdominal, gynaecological and paediatric assessment. Vascular ultrasound, for instance, allows us to see the blood flow in real-time thus making it possible to discern blocked arteries and veins. Musculoskeletal ultrasound allows us to image tiny tendons and nerves for degeneration or tears.