Radiology is the branch of medicine that looks inside you without surgery. X-ray, ultrasound, CT, MRI and nuclear medicine each have their own strengths, and a radiologist reads every image. This guide explains each scan, why your doctor chooses one over another, and how to understand your imaging report.
5modalities
X-ray, ultrasound, CT, MRI and nuclear medicine1specialist
a radiologist interprets every image0radiation
ultrasound and MRI use none at all24hwindow
most routine reports reach your doctor within daysA scan is a question, and the radiologist's report is the answer.
Tricorian LifeEach imaging method answers a different kind of question. Your doctor chooses the modality, and a radiologist interprets what it shows.
The original imaging test. A tiny dose of radiation photographs dense structures like bone. Fast, widely available, and the first choice for fractures, chest problems and many injuries.
High-frequency sound waves, no radiation. Excellent for soft tissues, blood flow, pregnancy, and guiding biopsiesBiopsyTaking a small sample of tissue so a pathologist can examine it. Imaging often guides the needle. in real time.
Computed tomography. An X-ray machine rotates around you and a computer rebuilds detailed cross-sections. Fast and thorough, so it is the workhorse for trauma, bleeding and deep structures.
Magnetic resonance imaging. Uses strong magnetic fields, not radiation, to build extraordinarily detailed pictures of soft tissue: brain, spine, joints, ligaments and organs.
A tiny amount of a radioactive tracer shows how organs and tissues are working, not just how they look. PET scans are central to cancer staging and treatment monitoring.
X-ray and CT use ionising radiation. Doses are kept as low as reasonably achievable, and the benefit of answering the clinical question outweighs the small risk. Ultrasound and MRI use no ionising radiation at all. ARPANSA explains doses in plain terms.
A scan passes through several hands before your doctor talks to you about it. Here is the route.
Your GP or specialist writes a referralReferralA letter from your doctor explaining why the scan is needed. Medicare rebates for imaging usually require one. stating the clinical question the scan must answer.
You book at a radiology practice. Some scans need fasting, drinking contrast, or metal removed. The practice tells you beforehand.
A radiographer performs the scan. Many scans take minutes; MRI can take 20 to 60 minutes, lying still.
A radiologistRadiologistA specialist doctor trained to interpret medical images and perform image-guided procedures. They write the report your doctor acts on. studies the images and writes the report, usually within days. Urgent results are called through faster.
Your referring doctor combines the report with everything else they know about you, and explains what it means for your care.
Imaging is a team sport. Each professional has a distinct role and their own years of training.
A medical specialist who interprets images, writes the report, and performs image-guided procedures. This is the doctor your images ultimately belong to.
The trained professional who performs your scan, positions you correctly and makes sure the images are high quality. Sonographers specialise in ultrasound.
A doctor who works with radioactive tracers to image function. Often works closely with oncologists for PET staging and treatment monitoring.
The GP or specialist who ordered the scan. They own the clinical question, receive the report, and are the right person to explain results in the context of your whole health.
Imaging reports have a structure. Knowing the structure makes them far less intimidating.
Most reports open with the clinical question, describe the technique used, then set out the findings in plain terms, and finish with an impressionImpressionThe radiologist's summary at the end of a report, condensing the findings into the key answer to the clinical question., the summary that answers the question your doctor asked.
ContrastContrastA dye, given by drink or injection, that makes structures stand out more clearly on CT and MRI. Most people tolerate it well; kidney function is checked first. highlights blood vessels, organs and abnormalities that would otherwise hide. It is given by mouth or injection, and your kidney function is checked before some types.
Most imaging ordered by a doctor attracts a Medicare rebate, but gaps vary between practices. Ask the practice for a quote before booking if cost matters to you.
Most routine reports reach your referring doctor within a few days. Urgent findings are phoned through quickly. Your referring doctor is the right person to ask about your specific result.
Doses are kept as low as reasonably achievable, and the information a scan provides usually outweighs the small risk. Ultrasound and MRI use no ionising radiation at all. If you have questions about a particular scan, ask your doctor or the practice.
For Medicare-rebated imaging, yes, a doctor's referral is required for most scans. Without a referral you may pay the full fee, and your images would not be interpreted in a clinical context.
Always tell the practice if you are or may be pregnant. Ultrasound is used routinely in pregnancy. X-rays and CT are avoided where possible or their benefit weighed carefully. MRI is sometimes used with caution.
The radiographer performs the scan and captures the images. The radiologist is the specialist doctor who interprets the images and writes your report. Both are essential.
Each modality answers different questions. MRI shows soft tissue detail, like ligaments, spinal discs and brain tissue, without radiation. CT is faster and better for bone, bleeding and emergencies. Your doctor chooses the test that best answers the question.
Reports normally go to your referring doctor, who explains them in the context of your whole health. Some practices give patients access to their images. The radiology report alone is rarely the full picture.
If you need guidance on understanding a scan, an imaging report, or the diagnostic pathway your doctor has suggested, reach out and our team will help. We respond within 24 hours.
Talk to our team or email [email protected]