Can You Have an MRI With Metal Implants, a Pacemaker or Screws?

Usually, yes. Plates, screws, joint replacements and most modern implants are scanned in the UK every day, and so are many pacemakers. But nobody can tell you that from a web page. The clinic needs to know exactly what is inside you, and its radiographer makes the decision on the day.

This article is general information, not medical advice. If you have symptoms that worry you, speak to your GP or call 111.

Why the scanner cares about metal at all

An MRI scanner is a very strong magnet, and it is always on. It does not switch off between patients and it does not switch off overnight. That single fact explains most of the safety questions you will be asked.

Three things can go wrong with metal in a magnetic field. It can be pulled or twisted if it is ferromagnetic. It can heat up when the scanner's radiofrequency pulses induce currents in it. And an active electronic device, such as a pacemaker or a nerve stimulator, can be interfered with.

There is a fourth, less dramatic problem: metal distorts the image around it. A large hip replacement can blur the picture for several centimetres in every direction. That is not a safety issue, but it does affect whether the scan will answer the question, which is worth knowing before you pay for one.

MR Safe, MR Conditional and MR Unsafe: the three labels

Medical devices sold anywhere in the world are labelled using terms defined by ASTM International in standard F2503. The MHRA's Safety Guidelines for Magnetic Resonance Imaging Equipment in Clinical Use (fifth edition, 2026) uses the same three terms, and they are the vocabulary your clinic will use.

MR Safe means an item poses no known hazard in any MR environment. In practice this covers things with no metal and no conductivity at all: a cotton blanket, a plastic catheter. Very few implants are MR Safe in this strict sense.

MR Conditional means the item has been shown to be safe in the MR environment within defined conditions. Those conditions are specific: a maximum field strength, sometimes a maximum scan mode, sometimes limits on which part of the body can be imaged and for how long. This is the category most modern implants fall into, and it is why the make and model matter so much. Two similar-looking devices from different manufacturers can have completely different conditions.

MR Unsafe means the item poses an unacceptable risk in the MR environment. Ferromagnetic surgical instruments are the textbook example.

The MHRA guidance adds a fourth practical category, MR Unlabelled, for anything carrying none of the three marks. Older implants and implants fitted abroad often fall here, and they take longer to check.

What this means for you, in plain terms

MR Conditional is not the same as "fine". It is closer to "fine, provided the scanner is set up in a particular way". The clinic's job is to look up your specific device, read the manufacturer's instructions, and configure the scan accordingly, or to tell you it cannot be done there.

This is also why "I had an MRI before, so I am fine" is not quite a safe assumption. Field strengths differ. A scan done on a 1.5 tesla machine does not automatically mean a 3 tesla machine will be used the same way. Mention the previous scan anyway, because it is genuinely useful information, but let the clinic draw the conclusion.

Pacemakers, defibrillators and other active devices

Active implanted devices are the category people worry about most, and historically they were an absolute barrier. That has changed considerably. Many cardiac devices implanted in the last fifteen years or so are designed to be scanned under defined conditions, and MRI in people with pacemakers is now routine in UK hospitals with the right arrangements in place.

Those arrangements are the point. Scanning someone with a cardiac device usually involves the device clinic reprogramming it before and after, monitoring during the scan, and agreement between the referring clinician, the MR clinician and, where needed, an MR safety expert. The MHRA guidance describes exactly this kind of collaborative decision.

Not every independent imaging centre offers it. If you have a pacemaker, an implantable defibrillator, a neurostimulator, a cochlear implant, an insulin pump or a programmable shunt valve, say so at the point of booking rather than on the day. It changes which clinics can help you, and it is better to find that out before you have paid.

If you have a cardiac device and you are getting new symptoms, that is a matter for your device clinic or your GP now, not something to investigate with a self-referred scan.

Plates, screws, joint replacements, stents and clips

Orthopaedic metalwork is the most common thing people ask about, and it is generally the least troublesome. Modern plates, screws, rods, nails and joint replacements are typically made from titanium or non-ferromagnetic stainless steel alloys, and they are imaged constantly.

Coronary stents, heart valves, aneurysm clips, embolisation coils, spinal fusion cages and surgical mesh are all scanned as well, under the same principle: identify it, look up its conditions, scan accordingly. Aneurysm clips in the brain are one group where the clinic will be particularly careful about establishing exactly which clip was used, because older designs and newer designs behave differently.

None of that is a ruling on your own metalwork. It is a description of how the process works.

The metal you might not think to mention

The safety questionnaire asks some questions that sound strange until you know why.

• Metal fragments in the eye. If you have ever ground, welded or machined metal, or had an injury with metal splinters, say so. It is common for clinics to arrange a plain X-ray of the orbits to check before scanning.
• Shrapnel, bullets and old injuries. Anything embedded that was never removed.
• Tissue expanders, ports and implanted lines, including chemotherapy ports.
• Contraceptive coils, dental implants, braces and retainers.
• Hearing aids, wigs with metal clips, and prosthetic eyes or limbs.

The question about metalwork at work is not idle curiosity. It is one of the few things a radiographer will stop an appointment for.

What to bring to your appointment

This is the part you can control, and it is the difference between a scan that happens and one that gets rescheduled.

Previous imaging is worth a separate mention. It is not a safety document, but it makes the new scan more useful, because the radiologist can compare. If you are arranging your own scan, ask whoever holds your earlier images for a copy before the appointment rather than after.

If you genuinely do not know what is inside you

This happens often, particularly with operations from decades ago or surgery in another country. It is not a dead end.

Your GP practice may hold the operation note. The hospital that did the surgery holds the record and will release it to you. The implant manufacturer can often identify a device from an X-ray appearance. And where nothing can be established at all, a plain X-ray sometimes tells the clinic what it needs to know.

Start that process before you book, not the week of the scan. If you are still working out where to go, our MRI search shows which UK centres offer what, so you can ask about your device before you commit.

Who actually decides

Not the receptionist. Not the booking form. Not this page.

The MHRA guidance is clear that safety screening happens before anyone enters the controlled area, and that risk and benefit for a particular patient are judged by a medical practitioner who knows that patient's situation, with the MR safety expert involved where the case warrants it. In practice, at a private imaging centre, the radiographer working with the MR clinician makes the call on the day, having read your form, your implant card and your history.

That is a feature, not an obstacle. It means the person deciding has the full picture, which no online checker ever does.

What the appointment itself is like

Assuming everything is cleared, the scan is uneventful. You lie still, the machine is loud, and you are given hearing protection. The MHRA guidance notes that noise inside the bore can approach 120 to 140 dB, which is why ear protection is standard rather than optional, and why clinics must make it available whenever levels could exceed 80 dB(A).

If you have not had one before, our guide to what to expect from an MRI scan covers the practical side: how long it takes, what you wear, and what happens if you need to stop.

Frequently asked questions

Do I need to know the make and model of my implant? Ideally yes. Many implants are MR Conditional, which means they can be scanned only under specific settings, and those settings differ between models. Bring your implant card, your discharge letter or the operation note. If you have none of these, tell the clinic early so they can chase the details.

Will a metal plate or screws set off the scanner? MRI has no alarm to set off. The questions exist because the magnet can pull on ferromagnetic metal, because radiofrequency energy can heat some materials, and because metal distorts the picture near it. Orthopaedic metalwork is scanned routinely, but the clinic still needs to know it is there.

Can I have an MRI with a pacemaker or defibrillator? Many modern devices are designed to be scanned under defined conditions, and MRI in people with cardiac devices is now common in the UK. It is not a decision a website can make. Your cardiac device clinic and the MRI centre agree it between them before the appointment.

What happens if I forget to mention something? Tell the radiographer as soon as you remember, even if you are already changed and waiting. They would far rather reschedule than scan without the full picture. Nothing about disclosing an implant late is embarrassing or unusual.

Does a dental filling, crown or IUD matter? Mention all of them on the form. Most dental work and most contraceptive coils are scanned without difficulty, but the clinic decides that, not you, and some items are worth a second look depending on which part of the body is being imaged.

If you are ready to look at dates and locations, you can compare MRI scans across UK clinics and raise your implant with the centre before you book.