Magnetic resonance imaging (MRI) is a scan that uses strong magnetic fields and radio waves to produce detailed images of the inside of the body. They can be used to examine many parts of the body. Results of an MRI scan can be used to help diagnose conditions, plan treatments and assess how effective previous treatment has been.
During the examination, you lie on a flat bed that's moved into the scanner.
Depending on the part of your body being scanned, you'll be moved into the scanner either head first or feet first.
The scanner is controlled by a radiographer, using a computer, which is in a different room, to keep it away from the magnetic field generated by the scanner.
You'll be able to talk to the radiographer through an intercom and they'll be able to see you on a television monitor throughout the scan. There is sometimes a mirror so that you can see the radiographer too.
At times during the scan, the scanner will make loud banging noises. This is the electric current in the scanner coils being turned on and off. Often earplugs or headphones are provided to reduce this noise. Some people find the MRI scanner uncomfortable if they are claustrophobic, a light sedative can be prescribed by your GP to make this more comfortable and some hospitals have “open scanners” that are less restrictive.
It's very important to keep as still as possible during your MRI scan.
Scans can last between 15 to 90 minutes, depending on the size of the area being scanned and how many images are taken.
MRI scans painless and safe, with no evidence to suggest there's a risk to the human body. Because MRI uses magnetic fields, if you have a metal implant such as a pacemaker, metal implants, clips, you may not be able to have an MRI scan. If you have any tattoos, there may be some warmth around the area.
My experience of an MRI Scan
By Susan, Make 2nds Count Community Member:
Some people get anxious about having scans but the way I see it and in an ideal world I’d want to take advantage of all the very best diagnostics available to keep track of what my cancer is doing and so that if necessary treatment can be modified. I had a very difficult period prior to diagnosis where I knew that I had doctors diagnosing and treating me by guesswork and that ultimately led to being diagnosed with Stage 4 Breast Cancer only after I had massive spinal damage. I’m certain that it’s really important to understand what the best diagnostics are and make sure that’s what you’re getting and because it can be confusing particularly when first diagnosed. So you hear people talking about having a scan but “what sort? Where? What in particular is it able to see and potentially diagnose?”
In some circumstances the CT is not quite as good at detecting detail whereby an MRI can be used to generate an image of almost any part of the body from the brain or spinal cord to bones. So particularly when there may be symptoms or known spread to the brain and certain areas of the liver or as for me there’s widespread bone spread including to the skull and so concern it might go to the brain and the spinal column and with a history of spinal cord compression which required extensive neuro spinal surgery. Then it shows up more detail so better on an MRI. I have those if there’s anything happening symptomatically that suggests an MRI is required or in any case annually.
An MRI takes much longer than a CT scan and you have to lie still in enclosed space in the machine from 20 minutes up to an hour. I’ve always been in for an hour.
When I’ve gone for the appointment there’s been no particular preparation so I can eat and drink as normal. Exception to this is if your abdomen is of particular concern and then you may be asked not to eat anything for a few hours prior. This helps to get a clear picture.
I always wear clothes with no metal so I don’t have to take anything off at all. Gone are the days of designer high heeled shoes and fancy outfits. Now I’ve bought pull on trousers and a crop top bra with no wiring or fastening especially for scan days. You can’t wear anything that is metal so I leave all jewellery (including watch & earrings) at home on scan days.
The radiologists are always very patient and considerate and take time to explain that for MRI, some people who have trouble with claustrophobia or are unable to hold their breath, which may be required for certain abdominal imaging tests, may find the procedure difficult. Some MRI machines can be configured in ways that may reduce claustrophobia or if you’re concerned then you may be able to have a sedative to help you relax. I’ve never personally needed that.
I often hear that you can’t have an MRI if you’ve metal in your body. So let’s get that straight: having something metallic in your body doesn't mean you can't have an MRI scan. Indeed I have massive titanium structure to fix my spine as well as orthopaedic implants in my shoulder and knees. Seems odd when you can’t even wear little metal stud earrings but it is how it is.
Medical implants, such as a pacemaker, brain stimulator, or other devices, are another complicating factor. The radio waves used with MRI can heat up devices made of metal. This is potentially a concern for something inside the body. Newer medical devices are usually designed with this in mind, so they are safe inside an MRI.
It’s important for medical staff carrying out the scan to be aware of any implants at all. Indeed you’d ordinarily discuss all this with your Oncologist when he’s talking about how he intends to proceed with diagnostics. If you’re not sure what sort or even where or whether you have metal implants or fragments in your body then you may need to have an X-ray first.
You will be asked to lie very still on a bed inside a cylinder (tube) either head or feet first and the bed moves slowly through the middle of the scanner. You will feel nothing at all but if like me you have such as metastatic cells in your back and spinal surgery and fixative implants it may be very uncomfortable to lie still on your back for such extended time. So I make sure I take a couple of painkillers on the day of the scan. For me it’s just a couple of paracetamol before. The scanner is very noisy and you will be given earplugs or headphones. When I’ve had my scans I’ve been able to listen to music and even have a choice of playlist during the scan.
The radiographer will leave the room once you’re in the right position on the bed but can see you through a screen and you’re also able to talk via an intercom while having the scan and they let you know what’s happening and make sure you’re ok throughout the scan. I find it helpful to close my eyes, think of something nice and drift away listening to the music when in the tunnel.
You can usually just go straight home and I tend to go have a little walk about so I don’t get too stiff and then get a nice coffee and a bacon sandwich at the hospital before setting off back to the car park and then home. Last time I went because of Covid and the distance I have to travel to the hospital, my Oncologist very kindly arranged for me to have my MRI and a CT scan all on the same day. Turned out to be a very good day because I had both scans within 2 hours and also had my first COVID Vaccine on the way down to the hospital.
Your Oncologist will usually let you know how long it will take to get your results back (usually between 1 and 2 weeks) and will let you know what the scan has shown. Some get anxious waiting for results though I’ve got to say that’s not me. The way I see it the results just let me and the doctors know what is actually happening. The fact I might not have known had I not had the scan is not a good thing and as far as my Oncologist is concerned, well I think that ignorance is not bliss. I want my treatment to be the very best in consideration of my situation and if there’s any change I want to know as soon as possible and if necessary get a new treatment plan and crack on with it. If it’s no change or improvement then of course this is fantastic news and I breathe a huge sigh of relief assured that my treatment is doing what it should and carry on living well with cancer. In my case I was told that “scans show her disease remains under control which is excellent news”. Too right ☺
I do know that if there’s something I’m concerned about I can talk it through with your family or friends. Don’t forget that Make 2nds counts are also able to support you and your hospital may have a Maggies Centre or MacMillan Nurses available to talk things through and help with any understanding.