Your GP hands you a referral slip, says the word “ultrasound”, and moves on to the next thing. You nod. Then you sit in the car park and start Googling.
Ultrasound is one of the most widely used imaging tests in Australian healthcare, and also one of the least explained. People turn up unsure whether to eat, what to wear or how much it will cost.
This guide clears that up. Here is how ultrasound works, how to prepare properly and what to expect once the gel comes out.
Key Takeaways
- Ultrasound uses sound waves instead of radiation, which makes it safe for children and during pregnancy
- Preparation depends entirely on the scan type: some need fasting, some need a full bladder, many need nothing
- Most appointments run for roughly 15 to 30 minutes and are painless
- A sonographer performs the scan, while a radiologist interprets the images and writes the report
- Medicare-eligible studies can be fully bulk billed, so many patients pay nothing
How Ultrasound Actually Works
An ultrasound machine sends high-frequency sound waves into the body through a handheld probe. Those waves bounce back off tissue, and the echoes are converted into a live picture on screen.
There is no radiation involved at any point. That is what makes it suitable for patients of all ages, including pregnant women and children, and why it can be repeated as often as your doctor needs.
The other advantage is that it happens in real time. A sonographer can watch a tendon move, track blood flow using Doppler imaging or guide a needle into position during a procedure.
The Scans People Get Referred For Most
Abdominal scans sit near the top of the list. They assess the gallbladder, liver, kidneys and spleen, usually when someone has persistent pain or digestive symptoms.
Women’s imaging is another big category, covering pelvic scans plus pregnancy dating, viability and morphology studies. Thyroid and neck lumps are common referrals too, as are testicular concerns and soft tissue lumps.
Musculoskeletal ultrasound is worth knowing about if you play sport. It can show a shoulder or tendon injury while the joint is actually moving, which a static image cannot do.
Vascular studies round out the list. Carotid Doppler scans and leg vein studies show how blood is moving, and abdominal aortic screening checks for aneurysms.
Preparation Is Where Most People Slip Up
Turning up unprepared is a common reason a scan has to be rebooked. The instructions can feel fussy, but each one exists to make the images clearer.
For an abdominal ultrasound, you fast for six hours. No food, no milk and no chewing gum, though small sips of water are fine. Fasting reduces bowel gas, which otherwise obscures the view of your organs.
Pelvic scans work in the opposite direction. You drink around a litre of water an hour beforehand and arrive with a full bladder, because that pushes the bowel out of the way.
Kidney scans also call for a full bladder, so avoid the bathroom for the hour before your appointment. Fasting is not required unless the kidney scan is being combined with an abdominal study.
Plenty of scans need no preparation at all. Thyroid, breast, testicular and musculoskeletal studies require neither fasting nor bladder prep, though it helps to wear clothing that gives easy access to the area being examined.
A few small things apply across the board. Take your regular medications unless told otherwise, let the clinic know if you are pregnant and arrive about five minutes early so check-in does not eat into your slot. If you have diabetes, ask about fasting rather than assuming.
Yes, it is a bit of admin for a routine test. The same logic applies to pre-employment medical checks, where a small amount of preparation up front saves everyone a wasted appointment later.
What the Appointment Itself Feels Like
You will be asked to lie on a bed and uncover the area being scanned. The sonographer applies gel to the skin, which helps the probe make proper contact.
The probe then glides over the area. You may feel mild pressure, particularly if the spot is already tender, but the scan itself is not painful.
Most examinations take 15 to 30 minutes. Simple studies are quicker, while detailed pregnancy or vascular scans can run a little longer.
For pelvic imaging, a transvaginal scan is sometimes offered when higher-detail views of the uterus and ovaries are needed. It is optional and always performed with consent, so ask questions if you feel uncertain.
Parents and carers can stay with their child throughout a paediatric scan. That single detail removes most of the stress for younger patients.
Who Performs Your Scan and Who Reads It
Two different professionals are involved, which catches people out. A sonographer runs the examination and captures the images, and a radiologist then interprets those images and writes the formal report.
The report goes back to whoever referred you. Your GP or specialist reads it alongside your symptoms and history, then explains what it means for you.
Sonographers generally will not offer a diagnosis during the scan, so try not to read anything into their expression. They are concentrating on capturing complete images, not withholding news.
You may notice long stretches of silence while they work. Capturing a usable image often means holding the probe at a very specific angle, and conversation makes that harder.
Occasionally a sonographer will step out to check something with the radiologist before you leave. It usually means they want an extra view while you are still on the bed, not that something alarming has appeared.
Ultrasound is also sometimes used alongside other imaging rather than instead of it. Your doctor may combine it with an X-ray or a scan of another type, depending on what the first set of images shows.
What It Costs and Where Bulk Billing Comes In
Cost worries people more than the scan does, and it is often the easiest part to resolve. Medicare covers a wide range of diagnostic ultrasound studies when you have a valid referral from a doctor.
Where a practice bulk bills, the Medicare rebate is accepted as full payment and you leave without a bill. Policies differ between providers, so it is worth confirming when you book rather than at the front desk afterwards.
Some clinics make this straightforward. Advicon Imaging Ultrasound in Sydney fully bulk bills all Medicare-eligible ultrasound examinations, with experienced sonographers performing scans using high-resolution equipment and radiologists reporting them.
Location is the other practical factor. Clinics spread across suburbs such as Gladesville, Hornsby and West Ryde mean a shorter trip, which matters when you are fasting or holding a full bladder in traffic.
Making the Most of Your Appointment
Bring your referral and any previous imaging you have of the same area. Comparison images give the radiologist far more to work with than a single scan on its own.
Wear something loose and easy to move. A shoulder scan is much simpler in a t-shirt than in a fitted jumper you have to wrestle off.
Finally, write your questions down beforehand. It is easy to forget them once you are on the bed, and the reception team can usually answer the practical ones before you go in.
The Bottom Line
Ultrasound is quick, safe and far less mysterious than the referral slip makes it feel. The two things worth getting right are preparation and expectations.
Follow the instructions your clinic gives you, ask questions when you are unsure and let the report reach your doctor before concluding. That really is all there is to it.
Frequently Asked Questions
Does an ultrasound hurt? No. The examination is painless, although you may feel mild pressure from the probe, particularly over an area that is already sore or inflamed.
How long does an ultrasound take? Most scans take about 15 to 30 minutes. Detailed studies, such as some pregnancy or vascular examinations, can take longer.
Do I need to fast before every ultrasound? No. Fasting is required for abdominal studies and abdominal aortic screening. Pelvic and kidney scans need a full bladder instead, and many other scans need no preparation at all.
Is ultrasound safe during pregnancy? Yes. Ultrasound uses sound waves rather than ionising radiation, which is why it is the standard imaging tool throughout pregnancy.
Do I need a referral? Ultrasound is a referred service, so your GP or specialist provides the request form. That referral is also what makes the Medicare rebate available for eligible studies.
When will I get my results? The radiologist’s report goes to your referring doctor rather than directly to you. Your GP or specialist will discuss the findings with you at a follow-up appointment.
