X-Ray, Ultrasound or MRI? Scans Explained

In 2022–23, Australians had 29.7 million Medicare-subsidised diagnostic imaging services — enough scans to outnumber the Australian population. And that does not even include every private, hospital or non-Medicare scan performed across the country. Diagnostic imaging has quietly become one of the most common ways doctors investigate pain, injuries, lumps, inflammation, pregnancy concerns, unexplained symptoms and ongoing health conditions.

Yet for something so common, scans can feel strangely confusing. Is an X-ray just for broken bones? Why would a doctor choose an ultrasound instead of an MRI? Does an MRI referral in Australia mean Medicare will cover it? Can you get a radiology referral online, and will an imaging clinic accept it?

If you have ever walked away from an appointment with a referral form and thought, “I’m not actually sure what this scan is looking for,” you are not alone.

This guide breaks down the everyday language of medical imaging in Australia. We will explain what common scans check, when doctors may recommend them, what happens during the appointment, what to ask before you book, and how online radiology referrals work when a telehealth consultation is clinically appropriate.

At NextClinic, we help Australians access telehealth consultations, prescriptions, medical certificates, specialist referrals and, when suitable, online radiology referrals. Our goal in this article is not to convince you that every symptom needs a scan — in fact, sometimes the safest and most evidence-based option is not to scan straight away. The goal is to help you understand what your doctor is weighing up, so you can feel more confident and less in the dark.

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First things first: what is diagnostic imaging?

Diagnostic imaging is the umbrella term for tests that create pictures of the inside of your body. These pictures help doctors describe, diagnose or monitor injury and disease. In Australia, diagnostic imaging includes X-rays, ultrasound, CT scans, MRI scans, nuclear medicine scans and other imaging tests.

Think of imaging like different camera modes on a phone — portrait, panorama, night mode, slow motion. They all “take a picture”, but they highlight different things.

An X-ray might be perfect for checking a possible fracture. An ultrasound might be better for looking at a tendon, gallbladder, pregnancy, testes or pelvic organs. An MRI might be useful when the question involves soft tissue, nerves, brain, spine or a joint injury that is not clearly answered by simpler imaging. CT, which we will touch on briefly, can be excellent for urgent internal injuries, kidney stones, some chest and abdominal problems, and many emergency settings.

The key point: the best scan is not always the most expensive or most detailed scan. It is the scan that answers the clinical question safely, accurately and efficiently.

“Referral” or “request”: why the wording matters in Australia

Most people say “radiology referral”, “x-ray referral”, “ultrasound referral” or “MRI referral Australia” when they mean the form a doctor gives them to take to an imaging clinic.

Technically, under Medicare language, diagnostic imaging commonly involves a request, while a referral usually refers to seeing a specialist or consultant physician. However, the terms are often used interchangeably by patients and imaging providers, and even many clinic forms use the word “referral”. MBS Online explains that diagnostic imaging requests apply to imaging services, while referrals apply to specialist and consultant physician consultations.

For practical purposes, when this article says radiology referral online, we mean the clinical request form for an imaging test — the document an imaging provider uses to understand what scan is being requested, why it is being requested, and who requested it.

A diagnostic imaging request generally needs to be in writing, whether manual or electronic, and contain enough information to clearly identify the service being requested. It must also be dated and include the requesting practitioner’s details, such as name and practice address or provider number. MBS Online notes there is no single standard request form and no specific timeframe in which a diagnostic imaging request is valid, although Medicare rules can apply when multiple services are ordered on one request.

That sounds administrative, but it matters because the imaging clinic needs the right information to perform the correct scan, apply any Medicare item rules, send the report back to the right clinician, and keep your care connected.

Why doctors order scans: the question behind the image

A good scan request is not just “sore shoulder” or “abdominal pain”. It usually starts with a specific clinical question.

For example:

• “Is there a fracture after a fall?”
• “Is this calf pain caused by a blood clot?”
• “Is there gallbladder inflammation?”
• “Is this knee injury likely to involve a meniscus or ligament?”
• “Is this pelvic pain related to ovarian cysts, fibroids or another gynaecological cause?”
• “Is this persistent cough associated with pneumonia?”
• “Is this lump solid, cystic, inflammatory or something that needs further assessment?”

This is why a doctor may ask detailed questions before issuing a referral. They are not just ticking a box — they are choosing the scan most likely to answer the question.

Sometimes imaging is urgent. Sometimes it is routine. Sometimes it is not the right first step at all.

For example, the Australian Commission on Safety and Quality in Health Care says that in most cases of low back pain, imaging such as X-ray, CT or MRI is not necessary, and scans are usually only needed when a clinician needs to rule out a serious cause. The same guidance notes that more than 95% of low back pain cases do not have serious underlying causes.

That can be surprising if you are in pain and desperate for answers. But it is an important reminder: more imaging does not always mean better care. A scan can sometimes reveal age-related or incidental findings that are not actually causing your symptoms, which can lead to anxiety, extra tests and confusion. The right scan at the right time is the goal.

X-ray referral: what X-rays are good for

An X-ray is usually the simplest, fastest and most widely available imaging test. It uses a small amount of ionising radiation to create images of body structures. Dense structures like bone show up differently from softer tissues, which is why X-rays are especially useful for bones and the chest. InsideRadiology, an Australasian radiology resource linked through RANZCR and healthdirect, explains that X-ray imaging is simple, quick and commonly used for the chest, arms, legs, spine, bones and joints.

When a doctor might recommend an X-ray

A doctor may consider an X-ray referral for:

• A suspected fracture after a fall, twist, impact or sports injury
• Persistent pain after trauma
• Joint alignment problems
• Chest symptoms where pneumonia, fluid, heart enlargement or lung collapse needs to be considered
• Some abdominal concerns, depending on the situation
• Checking arthritis or bone changes
• Follow-up of certain injuries or conditions

X-rays are particularly useful when the clinical question is about bone, alignment, air spaces or obvious structural change.

What happens during an X-ray?

Most plain X-rays are quick. You may be asked to stand, sit or lie in a certain position. A radiographer will position the area being imaged and ask you to stay still while the image is taken. Movement can blur the image, so holding still matters. InsideRadiology notes that plain X-rays often require no specific preparation, may take less than 15 minutes overall, and a simple chest X-ray can be very quick in an able and cooperative patient.

You usually do not feel anything during or after the X-ray. You may need to remove jewellery, watches or clothing with metal zips or clips, depending on the area being scanned.

If there is any chance you could be pregnant, tell your doctor and the radiology clinic before the scan. This does not automatically mean you cannot have imaging, but it helps the team choose the safest approach.

Are X-rays safe?

X-rays involve ionising radiation, so they should only be used when the expected benefit outweighs the risk. ARPANSA, the Australian Radiation Protection and Nuclear Safety Agency, explains that diagnostic X-ray imaging for patients should only be performed when it provides information that helps medical staff treat a patient’s condition appropriately, and that modern equipment can limit dose and the area irradiated.

In plain English: an X-ray is not something to fear when it is clinically justified, but it should not be used casually just because it is available.

Ultrasound referral: sound waves, movement and soft tissue

An ultrasound uses high-frequency sound waves to create moving images of the inside of the body. It does not use radiation and is commonly used in pregnancy, pelvic health, abdominal pain, gallbladder problems, kidney and bladder concerns, soft tissue lumps, tendons, muscles, blood flow and testicular concerns. Healthdirect notes that ultrasound is very safe, does not involve radiation and is safe to use during pregnancy.

Ultrasound is a bit like a live video rather than a still photo. That makes it useful when movement matters — for example, watching a tendon move, checking blood flow with Doppler ultrasound, or assessing a baby during pregnancy.

When a doctor might recommend an ultrasound

A doctor may consider an ultrasound referral for:

• Pelvic pain, heavy periods, suspected ovarian cysts, fibroids or other gynaecological concerns
• Pregnancy dating, growth or anatomy scans
• Gallbladder pain or suspected gallstones
• Kidney, bladder or urinary tract concerns
• Testicular pain, swelling or lumps
• Thyroid lumps or swelling
• Breast lumps, often alongside other breast imaging depending on age and clinical context
• Soft tissue lumps, hernias or fluid collections
• Tendon injuries, bursitis or some musculoskeletal problems
• Suspected blood clots or blood flow issues

For sexual and reproductive health, ultrasound can be part of the picture — for example, pelvic ultrasound for pelvic pain or irregular bleeding, or testicular ultrasound for pain, swelling or a lump. But it is important to know that ultrasound does not diagnose most STIs. STI testing usually involves urine, swabs and/or blood tests. If that is what you are worried about, our guide to STI window periods and test timing in Australia may be more relevant.

What happens during an ultrasound?

During most ultrasound scans, you lie on your back or side. Gel is placed on the skin, and a sonographer, radiologist or specially trained clinician moves a handheld probe called a transducer over the area. Healthdirect explains that you may feel gentle pressure, but it should not usually be painful, and many ultrasound scans take around 20 minutes.

Preparation depends heavily on the type of ultrasound.

You may be asked to:

• Drink water and arrive with a full bladder for some pelvic, kidney or bladder scans
• Fast for certain abdominal or vascular scans
• Wear clothing that allows easy access to the area
• Bring previous imaging for comparison
• Follow specific instructions from the radiology provider

For pelvic ultrasound, there may be an external scan over the lower abdomen, a transvaginal scan, or both. A transvaginal ultrasound involves placing a slim covered probe into the vagina and should only be done with your consent. If you are anxious, have pain, have a trauma history, have never had an internal examination, or simply do not feel comfortable, tell the sonographer. You can ask questions and discuss options.

MRI referral Australia: detailed imaging without X-ray radiation

MRI stands for magnetic resonance imaging. It uses strong magnetic fields and radio waves to create detailed images of the inside of the body. MRI does not use X-ray radiation and is particularly valuable for soft tissues, the brain, spine, joints, ligaments, tendons and some internal organs. Healthdirect explains that MRI can produce very detailed pictures, does not use X-ray radiation and is painless.

MRI often sounds like the “best” scan because it gives detailed images. But it is not automatically the right scan for every symptom. It can be more expensive, take longer, have stricter safety checks, and may not be Medicare-rebatable in every situation.

When a doctor might recommend an MRI

A doctor may consider an MRI referral for:

• Brain or spinal cord symptoms
• Certain headaches or neurological concerns after clinical assessment
• Persistent back or neck symptoms with red flags or nerve involvement
• Knee, shoulder, hip or ankle injuries where ligament, cartilage, tendon or soft tissue detail is needed
• Some tumours or cancer-related assessments
• Internal organ problems where MRI provides the best detail
• Follow-up of known conditions where MRI is the preferred imaging method

MRI can also be used after another scan. For example, an X-ray might rule out a fracture, while an MRI may later help assess ligament, cartilage or soft tissue injury if symptoms and examination suggest it is needed.

What happens during an MRI?

MRI takes longer than an X-ray or many ultrasounds. You usually lie on a table that slides into a tunnel-shaped scanner. The scanner can be loud, so you are usually given earplugs or headphones. You will need to lie still, and you may be given a buzzer so you can communicate with the radiographer. Healthdirect notes that MRI scans often take more than 10 minutes and can last up to 2 hours or more, depending on the scan.

Before an MRI, you will be asked detailed safety questions. Tell your doctor and the imaging clinic if you have:

• A pacemaker or defibrillator
• Cochlear implant
• Aneurysm clip
• Neurostimulator
• Metal fragments in the eye or body
• Certain heart valves or implants
• Infusion pumps
• Magnetic dental implants
• Medicine patches
• Kidney problems
• Allergies or asthma
• Claustrophobia
• Pregnancy or possible pregnancy

Some people with implants can still have MRI, but the device needs to be accurately identified and checked. Healthdirect warns that certain metal implants and objects can interact with the MRI magnet and cause serious harm, which is why the safety questionnaire is so important.

What about MRI contrast?

Some MRI scans involve an injection of contrast dye, often gadolinium-based contrast, to highlight certain tissues. Not every MRI needs contrast. The decision depends on the clinical question, the body part and the radiologist’s protocol.

If you have kidney disease, previous contrast reactions, allergies, asthma, pregnancy or breastfeeding concerns, raise this before the scan. The imaging clinic can explain whether contrast is needed and what precautions apply.

CT scans: where do they fit?

Although this article focuses on X-ray, ultrasound and MRI, you may also hear about CT scans. A CT scan uses X-rays and computer processing to create cross-sectional images — like slices through the body. Healthdirect describes CT as a 3D image of the body, while InsideRadiology explains that CT uses X-rays to obtain pictures for diagnosis.

CT is often used in emergency and urgent settings because it is fast and detailed. It can be useful for head injuries, internal bleeding, kidney stones, abdominal emergencies, chest problems and many cancer assessments. Because CT involves more radiation than a plain X-ray, the decision should be based on clinical need.

Which scan is “best”? The answer depends on the question

Here is a simple way to think about it.

An X-ray is often best when the question is: “Is there a fracture, chest infection, arthritis or obvious bone/chest problem?”

An ultrasound is often best when the question is: “What is happening with soft tissue, fluid, pregnancy, pelvic organs, testes, gallbladder, kidneys, bladder, tendons or blood flow?”

An MRI is often best when the question is: “Do we need detailed soft tissue, brain, spine, nerve, ligament, cartilage or internal organ information without X-ray radiation?”

A CT is often best when the question is: “Do we need fast, detailed cross-sectional imaging, often in an urgent or complex setting?”

But real life is messier. Two people can have similar symptoms and need different scans because of age, medical history, pregnancy status, injury mechanism, examination findings, red flags, previous imaging and Medicare rules.

That is why the consultation matters.

Medicare, bulk billing and imaging costs in Australia

Medicare covers many diagnostic imaging services through the Medicare Benefits Schedule, including MRI, ultrasound, CT scans and X-rays. However, Medicare coverage depends on the item number, clinical criteria, provider, equipment and request requirements.

The Australian Government notes that to be eligible for a Medicare rebate, MRI and PET scans must have MBS item numbers, be referred by a health practitioner, be provided by an accredited provider and be done on eligible equipment — and not all MRI machines are eligible. It also advises patients to check costs with the provider because not all imaging providers bulk bill.

This is one of the most common surprises for patients. You might have a valid MRI referral in Australia, but that does not always mean the scan will be bulk billed or fully covered by Medicare. Some MRI rebates have specific restrictions, including age, body part, clinical indication, frequency and who can request the scan. The Department of Health notes that MBS item restrictions can relate to gender, age, frequency of services and requestor requirements.

Before booking, ask the imaging clinic:

• Will this scan be bulk billed?
• If not, what is the out-of-pocket cost?
• Is this MRI being performed on Medicare-eligible equipment?
• Does my referral meet the MBS item requirements?
• Do I need to bring previous imaging?
• How long will results take?
• Will images and reports be sent to my referring doctor?
• Will results also appear in My Health Record?

It is much better to ask these questions before the scan than to be surprised by a bill afterwards.

Can you get a radiology referral online?

Yes, in many non-emergency situations, you can request a radiology referral online after a telehealth consultation with an Australian-registered doctor, if the doctor decides imaging is clinically appropriate.

At NextClinic, our online radiology referrals service is designed for adults in Australia who need a doctor to assess whether imaging is suitable. The scan might be an X-ray, ultrasound, CT, MRI, mammogram, DEXA or another imaging type depending on the clinical situation. The important part is that the doctor still makes the decision. An online form alone should not replace clinical judgement.

A radiology referral online may be suitable when:

• You have a non-emergency injury and need assessment for imaging
• A physio, specialist or another clinician has suggested imaging and you need a doctor to review the request
• You have a stable concern that can be safely assessed by telehealth
• You need follow-up imaging for a known issue
• You are trying to avoid delays because your usual GP is booked out

It may not be suitable when symptoms suggest you need urgent in-person care.

When online imaging referrals are not the right first step

Telehealth is convenient, but it has limits. If you have severe, sudden or dangerous symptoms, do not wait for an online referral.

Seek urgent medical care, call 000 or attend an emergency department if you have symptoms such as:

• Chest pain, severe shortness of breath or signs of a heart attack
• Face drooping, arm weakness, speech trouble or signs of stroke
• Sudden severe headache, confusion, seizure or loss of consciousness
• Major trauma, severe bleeding or suspected serious fracture
• New loss of bladder or bowel control with back pain
• Progressive leg weakness or numbness around the groin/saddle area
• Severe abdominal pain, especially with fever, fainting or pregnancy
• Sudden severe testicular pain
• Heavy bleeding in pregnancy
• A very unwell child
• Severe allergic reaction
• Thoughts of self-harm or a mental health crisis

In these situations, the priority is urgent clinical assessment, not simply obtaining a scan request.

How an online radiology referral usually works

The exact process varies between providers, but generally it looks like this.

1. You describe the problem

You provide details about your symptoms, injury, body part, timeline, medical history and what you are hoping the scan will answer. Be specific. “Left ankle rolled inward while playing netball yesterday, can’t bear weight, swelling over outer ankle” is much more useful than “ankle pain”.

2. A doctor reviews the request

The doctor considers whether imaging is needed, which scan is most appropriate, whether telehealth is safe, and whether you need in-person or urgent care instead.

3. If appropriate, a referral/request is issued

If imaging is clinically appropriate, the doctor issues the radiology request. You can take it to an imaging provider in Australia. Some imaging clinics require bookings for certain scans, while some X-rays may allow walk-ins, so always check.

4. You attend the imaging clinic

Bring the referral, Medicare card if you have one, previous imaging if relevant, and any instructions from the clinic. For MRI, bring implant/device information if applicable.

5. A radiologist reports the scan

The person taking the images is usually a radiographer or sonographer, depending on the scan. A radiologist — a specialist doctor trained in medical imaging — interprets the images and produces a report for the referring doctor. Healthdirect explains that MRI images are shown to a radiologist, who interprets the findings and provides a report to your doctor.

6. You follow up on the result

The report is only part of the story. Your symptoms, examination, history and goals matter too. A “minor” report finding can be important in the right context, while a dramatic-sounding finding may be old or unrelated.

At NextClinic, you can read more about how we manage imaging and test follow-up on our pathology and radiology results page.

What to tell your doctor before asking for a scan

A better referral starts with better information. Before a telehealth or in-person consultation, write down:

• Where the symptom is
• When it started
• Whether it followed an injury
• Whether it is getting better, worse or changing
• What makes it better or worse
• Any swelling, bruising, fever, weakness, numbness or weight loss
• Any pregnancy possibility
• Your medications, allergies and major medical conditions
• Previous surgeries or implants
• Previous scans and results
• What another clinician, such as a physio or specialist, has suggested
• What you are worried about

For musculoskeletal pain, our article on why we shouldn’t ignore “little” aches may help you think through patterns, triggers and when symptoms deserve attention.

If your scan is part of a bigger journey toward specialist care, you may also find our guides on navigating specialist referrals and how to fast-track your specialist referral useful.

How to read your radiology report without panicking

Radiology reports are written for clinicians, not for bedtime reading at 11:43 pm while you are already anxious. They can include technical language, uncertainty and incidental findings.

Common sections include:

• Clinical history: the reason for the scan
• Technique: how the scan was performed
• Findings: what the radiologist saw
• Impression or conclusion: the key summary
• Recommendation: any suggested follow-up, if needed

You might see phrases like:

• “No acute abnormality”
• “Clinical correlation recommended”
• “Mild degenerative change”
• “Incidental finding”
• “Further imaging may be considered if clinically indicated”

These phrases do not always mean something serious. “Clinical correlation” simply means the result should be interpreted alongside your symptoms and examination. “Degenerative change” can refer to wear-and-tear findings that are common with age and may or may not be causing pain.

If you are worried about a result, book a follow-up consultation. Do not try to diagnose yourself from a report alone.

Questions to ask before any scan

Choosing Wisely Australia, now hosted by the Australian Commission on Safety and Quality in Health Care, encourages patients to ask questions before tests, treatments or procedures to make sure they receive the right amount of care — not too much and not too little.

Before a scan, consider asking:

• What question are we trying to answer?
• Is this scan likely to change my management?
• Are there simpler or safer options?
• What are the risks, including radiation, contrast or incidental findings?
• What happens if we wait and reassess?
• How much will it cost?
• How will I receive the result?
• Who will explain the result to me?
• What should I do if symptoms worsen while waiting?

These questions are not “difficult” or disrespectful. They are part of good healthcare.

Common myths about X-ray, ultrasound and MRI

Myth 1: “MRI is always better.”

MRI is detailed, but not always better. It may be unnecessary, unavailable, more costly or less useful for certain questions. For a suspected simple fracture, an X-ray may be the right first test. For gallstones, ultrasound may be more appropriate.

Myth 2: “If the scan is normal, nothing is wrong.”

A normal scan is reassuring, but it does not always explain symptoms. Pain, inflammation, nerve irritation, early disease, functional problems and some infections may not show clearly on a particular scan.

Myth 3: “If the scan shows something, that must be the cause.”

Not always. Many people have disc bulges, tendon changes, cysts or age-related findings that are not the main cause of symptoms. Your doctor needs to match the image to the person.

Myth 4: “Radiation from one X-ray is always dangerous.”

X-rays do involve radiation, but when used appropriately, the benefit can far outweigh the small risk. The key is justification: only scan when the result will help guide care. ARPANSA emphasises that diagnostic X-ray imaging should provide information that helps treatment and that modern equipment can limit dose.

Myth 5: “An online referral means no real doctor reviewed it.”

A legitimate online radiology referral should involve an appropriately registered doctor assessing your symptoms and deciding whether imaging is clinically appropriate. If a service promises scans without assessment, be cautious.

Final thoughts: the right scan, at the right time, for the right reason

X-rays, ultrasounds and MRIs are powerful tools — but they are not interchangeable, and they are not always necessary.

An X-ray referral is often used for bones, joints and chest questions. An ultrasound referral is useful for many soft tissue, pregnancy, pelvic, abdominal, testicular, tendon and blood flow concerns. An MRI referral in Australia can provide detailed soft tissue, brain, spine and joint information without X-ray radiation, but Medicare eligibility and costs depend on specific rules. A radiology referral online can be convenient when your concern is non-urgent and suitable for telehealth assessment, but urgent or severe symptoms still need in-person care.

The most important takeaway is this: a scan should answer a meaningful clinical question. The best imaging is not the fanciest scan — it is the scan that helps you and your doctor decide what to do next.

This week, choose one practical strategy from this guide. Maybe you will write down your symptoms more clearly before your appointment. Maybe you will ask the imaging clinic about out-of-pocket costs before booking. Maybe you will ask your doctor, “What question are we trying to answer with this scan?” Or maybe you will book a follow-up to properly understand a result instead of spiralling through search results alone.

If you try one of these strategies, share it in the comments: which one did you choose, and did it make the process clearer or less stressful?

References

• Pathology, imaging and other diagnostic services - Australian Institute of Health and Welfare
• Diagnostic services Overview - Australian Institute of Health and Welfare
• Low Back Pain Clinical Care Standard | Australian Commission on Safety and Quality in Health Care
• Plain Radiograph/X-ray - InsideRadiology
• X-rays | ARPANSA
• Ultrasound - types and preparation | healthdirect
• MRI scan | healthdirect
• CT scan - computed tomography | healthdirect
• What Medicare covers | Australian Government Department of Health, Disability and Ageing
• What we’re doing about diagnostic imaging | Australian Government Department of Health, Disability and Ageing
• 5 questions to ask your doctor or other healthcare provider before you get any test, treatment, or procedure | Australian Commission on Safety and Quality in Health Care

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