Diagnosing MS

How do I know if I have MS?

MS can affect people in different ways, and no one knows which symptoms someone will have or for how long. Before you can understand the tools and approaches healthcare professionals use to make a diagnosis, it is important to recognize the symptoms of MS and understand their impacts.

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Charlie’s story

MS causes a wide range of symptoms

The signs and symptoms of MS vary depending on the specific areas of the central nervous system (CNS) being affected.

Some of the early symptoms are often so mild or unclear that they are hard to recognize, even for a physician. However, in some situations, they can be more severe and more abrupt.

Heat and fatigue can exacerbate other MS symptoms.

Types of symptoms

Some of the more common symptoms of MS are outlined below.

Relapses and remissions

Most people with MS experience relapses.

In MS, a relapse – also called an exacerbation, attack, or flare-up – causes new symptoms or the aggravation of old ones. Relapses range from very mild to severe enough to affect a person’s daily life, and they vary greatly. 

To qualify as a true relapse:

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Lasts at least 24 hours

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Happens at least 30 days after the last relapse

Let a doctor know if you have new or worsening symptoms.

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Relapse terms and facts

Most relapses last from several days to a few weeks or months.

When symptoms get less severe or briefly disappear, this is called a remission.

While some relapses cause only one symptom, others may cause two or more symptoms.

 pseudo-relapse is a temporary increase in MS symptoms due to outside stressors, (like the flu) that disappear when the stressors are gone.

Rick's story

Assessing the impact of MS on mobility

Mobility means different things to different people.

For some, it means being able to go on long runs or hikes, while for others it means being able to walk and perform their daily activities just like they always have. No matter what mobility means to you, the ability to get from A to B is something that is important to all of us.

The primary tools used for evaluating functional mobility are known as the Timed 25-Foot Walk (T25-FW) test, the Timed Up and Go (TUG) test and the 9-Hole Peg Test (9-HPT).


The T25-FW is a test based on a timed 25-foot walk used to measure walking ability in people with MS.

  1. Patients are asked to walk 25 feet on a clearly marked course as quickly and safely as they can.
  2. The time is calculated from when the patient is told to start and ends when they reach the 25-foot mark.
  3. They are then asked to repeat the task right away by walking the same distance back to the start.


The purpose of the TUG test (or Get Up and Go Test) is to identify those at risk of falling. It can also screen for balance and gait problems. 

The patient is observed as they: 

  1. Stand from a sitting position, without using their arms for support.
  2. Walk 10 feet, turn and return to the chair.
  3. Sit back in the chair, without using their arms for support.
Those patients who have trouble completing the test in less than 10 seconds or are unsteady need to be further assessed.

In the follow-up, the patient is asked to: 
  1. Stand from a sitting position, without using their arms for support.
  2. Close their eyes for a few seconds, while standing still.
  3. Stand with their eyes closed while somebody gently pushes on their sternum.
  4. Walk a short distance and stop.
  5. Turn around and return to the chair.
  6. Sit, without using their arms for support. 


The 9-HPT is an arm and hand function test in which both the dominant and non-dominant hands are tested twice.

  1. A block with 9 holes is placed on the table in front of the seated patient along with a small container with 9 pegs.
  2. While being timed, the patient has to pick up one peg at a time, using only the hand being tested, and put it into the holes as quickly as possible.
  3. Once all pegs are placed into the holes, the patient has to then remove them, one peg at a time, and return them to the container as quickly as possible.
The total time to complete the task – placing and then removing the pegs – gets recorded. The routine is repeated twice for each hand. 

Timely and accurate diagnosis

Prompt and correct diagnosis of MS is important for many reasons:

  1. Clarity:
    If someone is living with unfamiliar and distressing symptoms, knowing the reason for their discomfort can be reassuring. A diagnosis also allows a person to begin the adjustment process and helps relieve worries about other diseases, such as cancer.

  2. Proper testing and treatment:
    In an MS diagnosis, taking a patient’s medical history and giving them a neurological exam are essential. And, since permanent neurological damage can happen even in the earliest stages of MS, it is critical to establish a diagnosis, so that the proper treatment options can initiated as early on as possible. 

  3. Documentation:
    A diagnosis of MS needs to include proof of disease activity separated in time and to document the location of lesions in the CNS.
It may take some time for an MS diagnosis to be confirmed. It is also important to keep in mind that there is not necessarily one single test that can be used to diagnose MS and that a diagnosis can only be made after any other potential causes for symptoms have been excluded. 

MS rating scales

The Expanded Disability Status Scale (EDSS) is a tool used to assess mental and physical ability. A trained examiner, such as a doctor or neurologist, will carry out an examination looking at general ability. The Functional Symptom Score (FSS) may also be used, which looks at specific functional areas such as visual, sensory, and bowel and bladder functions. 

The EDSS is a clinical rating scale based on the judgement of the examiner, and scores range from 0 to 10 in half-point increments.

The score increases the more the patient’s ability is affected. 


Any changes in symptoms should be discussed with a doctor.


Doctors may use several different tests to diagnose MS because there is not one unique test for MS. The tests help doctors rule out other conditions.

The main tests are:

Neurological exam

This is one of the first tests a doctor will perform. The exam looks at a person’s cognition, coordination and strength, vision and hearing, and other senses. 

Magnetic resonance imaging (MRI)

Currently, MRI offers the most accurate and non-invasive way to get images of the brain, spinal cord or other areas of the body. MRI makes it possible to evaluate the underlying progression MS and is the tool of choice for diagnosing MS and tracking the progression of the disease. 

Evoked potentials (EP)

EP tests measure the electrical activity of the brain and are used to find out if sensory nerve pathways are working properly. This helps detect any damage done to the nerves, especially when the change is subtle or may not have been noticed by the patient or shown up on neurological examination. 


EP tests are very useful when MRI findings are surprisingly normal or borderline. No needles or injections are used and there is no radiation – making it safe to undertake even during pregnancy.

Cerebrospinal fluid (CSF) examination

CSF is a clear, colourless liquid that surrounds the brain and spinal cord.


While the primary role of CSF is to protect the brain within the skull (like a shock absorber), it also distributes nutrients and chemicals filtered from the blood and eliminates waste products from the brain. 


In people with MS, this fluid shows specific changes that match up with the presence of inflammation. 

The important role of MRI

MRI can enable people to plan their next steps.


Magnetic resonance techniques have had a major impact over the last two decades in understanding MS. The imaging guidelines for MS are broadly divided into approaches for imaging patients with suspected MS or for monitoring patients with established MS.


MRI uses a huge magnet, radio waves, and computer software to take two-dimensional pictures of the inside of the body. During the test, a person will lie in the MRI machine for 15 to 30 minutes.

The MRI machine produces a unique sound (like loud, fast knocking) that might surprise people if they do not know it is coming. A technician will be on hand to notify individuals of what they can expect and help answer any questions. 

It may seem a little cramped in the MRI machine. Those who have a difficult time being in confined spaces may wish to consult with their doctor.



An MRI may sometimes include contrast materials, which are substances used to improve the images of body organs and tissues. They are often used to visualize certain types of MS disease activity on the MRI.



MRI has enhanced our ability to diagnose the disease, which in turn allows for earlier treatment exploration.

Because MRI is also a tool that helps track the progression of the disease, assessing progression can help individuals make informed decisions on treatment options. 


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