MRI scans are very noisy procedures; you will be provided with ear protection in the form of ear defenders / ear plugs, depending upon the type of scan you are having. The length of the scan can vary from 10 minutes to an hour, however, the average duration is around 20–30 minutes.
The scanner consists of a long tunnel with a room at either end. The body part you are having scanned will need to be placed into the middle of this tunnel. In some instances, we are able to perform the scan with your feet entering the scanner first. This is usually the case if we are scanning part of your body that is below waist level.
Upon arrival, please make yourself known to the mobile scanning unit by knocking on the door and waiting for attention. If we are not quite ready for you, you may be asked to wait in your car and complete some paperwork.
The radiographer will maintain verbal contact with you during the scan via an intercom system. Should you require their attention urgently, a buzzer will be provided.
Can I have an MRI scan?
As MRI scans involve the use of a large magnetic field, there are some instances where it may be unsafe for us to perform your scan. You will be asked to complete a safety questionnaire over the phone at the time of booking your appointment, we will also double-check these questions with you when you attend for your scan. It is important that we are made aware if you have / have ever had any of the following:
- Cardiac pacemaker / implanted cardiac defibrillator
- Heart surgery (including stents / valves)
- Intracranial aneurysm clips
- Surgical implants
- Metallic fragments in your eyes or skin
- Surgical procedure in the six weeks prior to your appointment
- Neurostimulator
- Cochlear Implant
- Weight of over 25 stone/150kg
- Claustrophobia (your GP may be able to prescribe a sedative to take before your scan)
- Possibility of pregnancy
For patients who are wheelchair users, we can scan patients who are able to walk the length of the scanner with assistance. However, due to the size of the unit and the fact that most wheelchairs are not MRI compatible, we are not able to scan patients who are physically unable to get out of a wheelchair.
Please also let us know of any mobility problems, we will be happy to arrange assistance for you should it be required.
It is also beneficial if you can remove jewellery/piercings before you attend your scan. Please try to limit the amount of metal on your clothing by wearing items such as jogging bottoms. You may be required to change into a gown if you are wearing clothing with zips/clips etc. Limited changing facilities are available.
Do I need a referral?
A contrast MRI scan requires a valid referral from either a GP or a specialist consultant prior to your appointment.
Contrast MRI scans involve the injection of a gadolinium-based contrast agent, which enhances the visibility of certain tissues and abnormalities on your scan. While generally safe, contrast agents carry a small risk of side effects — including allergic reactions and, in rare cases, complications for patients with reduced kidney function.
For your safety, a referring clinician must:
- Confirm that a contrast scan is clinically appropriate for your condition
- Review your medical history for any contraindications (such as kidney disease, previous allergic reactions to contrast, or pregnancy)
- Take clinical responsibility for the referral in line with UK medical and imaging guidelines
If you don’t currently have a GP or specialist referral, we can help. We offer a virtual GP consultation for £50, during which one of our clinicians will assess your symptoms and medical history. If a contrast MRI scan is clinically appropriate, they will issue a referral at the end of the consultation so you can proceed with your booking.
How does an MRI scanner work?
Magnetic Resonance Imaging (MRI) involves the use of a large magnetic field and radiofrequency waves to collect signal from the hydrogen protons within your body. The protons become magnetised as they enter the magnetic field, we then apply radiofrequency waves which manipulate their magnetisation.
As soon as the radiofrequency is turned off again, the protons relax back to their initial state, emitting energy / signal as they do so. Different tissues emit different amounts of signal, this allows an image with differing greyscales to be produced according to the amount of signal acquired. We use pieces of equipment called ‘coils’ to collect this energy / signal. Coils are usually placed on or around the body part we are scanning.
The signal is then converted to an image via a computer algorithm. The scan is split into 3-4 minute sections and we usually produce pictures showing different orientations. It is important to remain very still during the scan to avoid any blurring of the images.
To date, there are no known side effects of an MRI scan. Unlike CT scans and X-rays, MRI scans do not use ionising radiation.
Additional important information
Your MRI scan will be performed on one of our mobile scanning units. We therefore have limited facilities on board. We are unable to provide waiting facilities for family members / friends who may be accompanying you to your appointment. At some of our sites, there may be waiting rooms separate from the scanning facility, however, this can not be guaranteed.
We are unable to provide an area for children to be left, and they cannot enter the mobile unit with you, so you will need to make other arrangements for their supervision.
Toilets are not available on board the unit. If necessary, you may be asked to use the facilities on the site where we are scanning (this can include supermarkets and football clubs).
Please try not to bring any valuables with you. You will be required to empty your pockets before entering the scan room. Handbags will not be permitted into the scan room as they can contain multiple magnetic items. Limited locker space is available for you to leave your belongings if necessary. Patient gowns can be provided, and you will be able to get changed on the unit.
How do I get my results?
Following completion of the scan, your images are interpreted by a consultant radiologist (a doctor who specialises in medical imaging). The radiologist will issue a report on the images and return it to your referring clinician (GP, physiotherapist, specialist).
Upon request, we are able to send your images to the majority of NHS Trusts within the U.K. Please discuss with your referrer, as they will need to arrange with us for this to happen. This may be the case if you are referred for specialist treatment following your scan.
Further information is available at the following website: www.nhs.uk/conditions/mri-scan
