MRI scan for multiple sclerosis and clinically isolated syndrome

Multiple sclerosis (MS) and clinically isolated syndrome (CIS) can be diagnosed by an MRI scan.

Normal MRI scans effectively rule out MS as a patient’s symptoms, although it doesn’t mean that they cannot develop MS in the future.

Positive MRI scans show white dots (lesions) that have the characteristic appearance of inflammation.

It's normal for an adult patient to have a few age-related white dots on their scans and are often described as microvascular lesions. An expert (neuroradiologist or trained neurologist) will be able to differentiate between inflammatory lesions and microvascular lesions based on where they are in the white matter.

MRI scans of the cervical cord can be helpful as you do not get microvascular lesions in the spine.

Patients with MS or CIS (which has a high risk of becoming MS), will have something called dissemination in time and space, which means new inflammatory lesions appearing on a second scan or some that enhance (take up dye) and some that don’t.

Repeat scans will often be done to look for new lesions. Having no change doesn’t mean that the patient will never have MS, but it does show that the condition is currently quiet and the patient doesn’t need active treatment.