Is the EOS Scan Safe? Radiation Dose Explained
Yes, the EOS scan is safe for adults. It uses about 90% less radiation than a standard X-ray, around ten times less. This makes it one of the lowest-dose imaging options available for checking bones, joints and full-body alignment while you stand in a natural, weight-bearing position.
Key points
- The EOS scan gives about 90% less radiation than a standard X-ray, around ten times less.
- There are no known side effects from a single EOS scan at this low dose level.
- You stand upright during the scan, so gravity and your muscles are at work, just as in daily life.
- EOS shows bones, joints and alignment. For soft tissue, discs or nerves, MRI is usually the better tool.
- No referral is needed. ScanAlign is a private, self-pay clinic at 19 Harley Street, London.
You may have been told you need an EOS scan. Or you may be thinking about one for a long-standing back, hip or knee problem. Either way, your first question is probably about safety. That is a sensible thing to ask about any scan that uses radiation. This page explains exactly how much radiation the EOS system uses, how that compares with other scans, and why the dose is so low.
What is radiation dose and why does it matter?
Radiation dose is the amount of energy your body absorbs during a scan. A lower dose means less exposure and a smaller theoretical risk. All medical imaging that uses X-rays carries some radiation. But modern systems are designed to keep the dose as low as reasonably achievable. This principle is called ALARA, and it guides every scan at ScanAlign.
In everyday terms, we are all exposed to low levels of natural background radiation from the ground, the air and even the food we eat. A single EOS scan adds a fraction of what you would receive from background radiation over a few days.
How does EOS radiation compare with a standard X-ray?
The EOS system uses about 90% less radiation than a standard X-ray, around ten times less. This is possible because of the technology behind it. The EOS detector was developed from Nobel Prize-winning particle physics research by Georges Charpak. It is extremely sensitive to X-ray photons, so it needs far less radiation to produce a clear, detailed image.
A standard set of spine X-rays may need several separate exposures, each at a higher dose. The EOS system captures your whole body in one standing pass, so the total exposure stays very low.
Does an EOS scan have any side effects?
No. There are no known side effects from a single EOS scan. The radiation dose is so low that it falls well within the levels the UK Health Security Agency and international radiation protection bodies consider safe for diagnostic imaging. You will not feel anything during the scan, and there is no recovery time afterwards.
The scan does not use contrast dye or injections, so there is no risk of an allergic reaction. You simply stand still inside the scanner for a few seconds while it takes your images.
Want to know what happens during the scan, including how to prepare and what to wear? Visit our frequently asked questions page for full details.
Why does standing up during the scan make a difference?
Standing up during the scan is just as important as the low radiation dose. When you lie down for a standard X-ray, CT or MRI, gravity no longer pulls on your skeleton in the usual way. Your muscles relax, your spine settles, and alignment problems can flatten out or disappear completely. This means lying-down images may miss the very issue causing your pain.
The EOS system images you upright, weight-bearing and in your natural posture. Your body is a connected chain from your feet to your head. If your pelvis tilts slightly, your spine adjusts above it, and your knees compensate below. A problem in one area can cause symptoms somewhere else entirely. Standing, whole-body imaging shows these compensations in a way that single-area, lying-down scans cannot.
This is why a scan at ScanAlign captures your whole body while you stand. You get an accurate picture of how your skeleton really behaves under load, with a radiation dose that is about 90% less than a standard X-ray.
When is MRI better than an EOS scan?
MRI is usually the better choice when your clinician needs to see soft tissue. EOS shows bones, joints and alignment with outstanding clarity. But it does not show discs, nerves, ligaments or cartilage in the same detail as MRI.
Good to know: EOS and MRI work together. They are not competitors. EOS is excellent at showing your skeletal alignment in real-world, standing conditions. MRI is excellent at showing soft-tissue problems such as disc herniations or nerve compression. Many patients benefit from both, depending on their symptoms and what their clinician is looking for.
Before you start treatment, or change the treatment you are on, it is worth getting a detailed diagnosis. Knowing whether the cause sits in the pelvis, the legs or the spine changes what will actually help.
Frequently asked questions about EOS scan safety
Yes. The EOS scan uses about 90% less radiation than a standard X-ray, around ten times less. This is well within the safety levels set by UK and international radiation protection guidelines.
The EOS system gives about 90% less radiation than a standard X-ray, around ten times less. The exact dose depends on the area scanned and your body size. Even so, it is one of the lowest-dose X-ray systems available.
No. There are no known side effects from a single EOS scan. You will not feel anything during the procedure. No contrast dye or injections are used.
Any X-ray-based imaging is generally avoided during pregnancy as a precaution. If you are or might be pregnant, please tell us before booking. Your clinician can advise on the most suitable imaging option for your situation.
The EOS detector technology was developed from Nobel Prize-winning particle physics research. Its sensors are extremely sensitive to X-ray photons. This means a clear image can be taken with far less radiation than conventional systems need.
No referral is needed. ScanAlign is a private, self-pay clinic. You can book directly through a free video consultation, where we discuss whether the scan is right for your situation.
The scan itself takes around 15 to 20 seconds. Your full appointment, including positioning and any questions, usually lasts a bit longer. There is no recovery time, and you can carry on with your day straight afterwards.
EOS is designed to show bones, joints and skeletal alignment. For soft tissue detail such as discs, nerves or ligaments, MRI is usually the better tool. The two scans complement each other well.
When you lie down, gravity stops pulling on your skeleton and your muscles relax. Alignment problems can flatten out and disappear. Standing imaging shows how your body really works under load. It reveals compensations and misalignments that lying-down scans may miss.
Have a question about EOS scan safety?
Speak to our specialist radiographer in a free video consultation, with no obligation. We will explain what the scan involves and whether it is right for you.
Book a free video consultationWritten by Abbas Dhami (Specialist Diagnostic Radiographer)
Sources
- Deschênes S, Charron G, Beaudoin G, et al. "Diagnostic imaging of spinal deformities: reducing patients' radiation dose with a new slot-scanning X-ray imager." Spine, 2010; 35(9): 989-994.
- UK Health Security Agency (formerly Public Health England). "Guidance on diagnostic radiology: patient doses." GOV.UK.
- Melhem E, Assi A, El Rachkidi R, Ghanem I. "EOS biplanar X-ray imaging: concept, developments, benefits, and limitations." Journal of Children's Orthopaedics, 2016; 10(1): 1-14.
This page is general information and not a diagnosis.
ScanAlign is the trading name of CoreMed Solutions Ltd and operates under The Harley Street Hospital's CQC licence.