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The Story behind the MRI process in Multiple Sclerosis


By Therese Burke, MS Nurse

An international group of neurologists and radiologists have developed guidelines to be used to assist in both the diagnosis of Multiple Sclerosis (MS), and the ongoing follow-up of MS. These guidelines involve the use of magnetic resonance imaging (MRI). The MRI is not an x-ray and does not expose you to radiation, rather it uses magnetic fields, radio waves and a computer to produce images which show up areas where myelin has been damaged, often looking like a white patch on the scans. If you have been diagnosed with MS, it is highly likely you have been through the process of having an MRI scan.

There are two primary reasons why the MRI is so important in MS. Firstly, the MS MRI guidelines are vital to contribute to an accurate diagnosis of MS after you have your first symptoms (or “relapse” of MS), even at a time when you may have only had one episode of symptoms.  They take into account the differences between lesions from MS and lesions from other diseases that may mimic (or look like) MS. An accurate diagnosis in the beginning is obviously very important and an MRI can both rule out other possible diseases, as well as support the diagnosis of MS.  The lesions in MS have specific shapes and special locations where they tend to occur, often near blood vessels in the brain, as well as in the optic nerves and spinal cord. In addition to detecting lesions, the MRI can also indicate areas of atrophy, or shrinkage of the brain and spinal cord, an area of MS which is becoming increasingly significant and will be important in the future treatment and understanding of MS.

There is not one test to diagnose MS, and the MRI is part of several things that your neurologist will consider - you may also have electrical conduction tests, eye tests, blood tests and physical/neurological examinations to help track the cause of the problem/s. The exact location of the lesions in your brain, optic nerves and/or spinal cord on the MRI may also be helpful to the neurologist in making decisions about which treatment might be best for you in your particular situation, as well as when to start treatment. If you have ever only had one single episode of symptoms (called clinically isolated syndrome or CIS), the MRI is also an important way to monitor you in the future to see if new lesions develop, which may change your diagnosis to definite Multiple Sclerosis, if and when new lesions occur.

Following on from your diagnosis of MS, regular MRI’s are very important to track your progress. These days neurologists like to see a concept called NEDA in their RRMS patients - which means No Evidence of Disease Activity  - or put more simply, no new clinical relapses and no new signs of activity on the MRI. This involves checking to see if new lesions have developed since your last MRI. This brings up two key concepts in ongoing MS disease monitoring- new lesions since your last MRI that may have occurred a long time before now (perhaps even the week after your last MRI) and are inactive, or new lesions from your last MRI which are active either right now or within the last few weeks.

By using an injection (also called “contrast” and is usually a compound called gadolinium) with the MRI, the neurologist and radiologists are also able to differentiate, or tell the difference between, new lesions that have been there for a bit longer since your last MRI, or lesions that are fresh and causing new activity. Any fresh lesions light up brightly on a special view on the scan. This can also be important in deciding if you are currently undergoing a relapse and may need immediate treatment. It is also possible to have new lesions develop which produce no symptoms to you at all, and therefore detection on the MRI may alert the neurologist that you have MS activity that is going on beneath the radar. This is important in Relapsing Remitting MS in case you need a change to your MS treatment and escalation to a more potent, or different class, of therapy. Remember that, just like MS symptoms are different for everybody, the way you respond to an MS treatment is also different for everybody. Your neurologist will discuss the results of the MRI with you and whether they are happy for you to remain on your current treatment, or you whether you might require a change.

For people living with Secondary Progressive MS (SPMS) or Primary Progressive MS (PPMS) you may undergo MRIs less frequently than people with RRMS, but they are still an important part of your monitoring plan to check your progress and help the neurologist with decisions concerning your treatment. Hopefully as research into SPMS and PPMS escalates, there will be greater treatment options for you in the near future.

No discussion about MRIs would be complete without mentioning that for some people, MRIs can be terrifying! This can be difficult for others who have no bother with MRIs, or similar tests, to understand. For a variety of reasons, to some individuals MRIs can feel claustrophobic, being in the “tunnel” and feeling at a distance from the technicians sitting outside the room. The whirling noises from the machine can also be bothersome for some, leading to just mild anxiety or even outright terror. You must let the MRI staff know well in advance of your scan if you think you may have issues with the scan so that appropriate measures can be taken for the staff to help you, this can include things like sedation on the day. As MRIs are an important part of your MS management, finding a solution to lessen your worry in the future is very important, and the staff will understand.

Brain Health3 is an important new resource, which gives excellent guidance to both medical and allied health staff and to people living with MS, about the importance of MRI surveillance and is a great addition to your knowledge go-to portfolio. There are many sources of information about MRIs, none more important than your treating neurologist, MS Nurse, radiologist and MRI staff. If you have any questions or concerns, please let them know so that they can help you.


1Summary of MRI protocol and Guidelines prepared by The Consortium of MS Centres (CMSC), Hackensack, NJ, USA. Downloadable from

2Giovannoni G et al. Is it time to target no evident disease activity (NEDA) in Multiple Sclerosis?Mult Scler Relat Disord (2015); 4 (4): 329-333.