Skip to main content Skip to navigation

Diagnosing MS

Getting a diagnosis of MS can be a long and difficult process, not least because the symptoms of MS are common to many other conditions. Many people with MS say that handling the uncertainty during and following diagnosis is harder than coping with any of the symptoms they ever experience. Knowing what to expect during the diagnosis procedure and understanding what the various tests are looking for can help to make the process easier to deal with.

There is no one test or procedure that can be used to accurately diagnose MS on its own. Diagnosis is usually based on a history of symptoms (perhaps an unexplained episode of blurred vision years before, or pins and needles in the hands or feet) and on the results from a series of tests. Doctors need to rule out other possible causes of symptoms before they can confirm a diagnosis of MS.

If you experience symptoms for the first time, and then they improve or disappear, neurologists often prefer to wait for a second relapse, or for symptoms to become more severe, before giving a definite diagnosis.

Medical (clinical) history

Your doctor will ask about your medical history and symptoms and may perform some simple physical examinations.

MRI scanning

Magnetic resonance imaging (MRI) scans are used to identify any areas of scarring in the brain or spinal cord.

More information on MRI

Evoked potentials

These are simple electrical tests, carried out on vision, which can detect a delay in messages between the eyes and the brain.

More information on evoked potentials

Lumbar puncture

This procedure involves drawing off a sample of fluid from around the spine and testing for abnormalities that can indicate MS.

More information on lumbar puncture

It is important to note that the above tests do not always give a definitive result. For most people with MS, an MRI scan will show some lesions or areas of inflammation, but there is a small proportion of people who have a 'silent' MRI. Similarly around 5% of people with definite MS will have a negative lumbar puncture result.