Multiple sclerosis (MS) causes damage and scarring to nerve tissue. This damage can result in lesions in the brain that can affect balance, vision, and other functions. Doctors can identify MS brain lesions with different imaging techniques.
In addition to monitoring the state of MS, doctors can use MRI scans to chart the disease’s progression and a person’s response to treatment.
Below, learn how these scans detect MS lesions, what these lesions are, and what treatments are available.
We also discuss how a person can prepare for an MRI scan.
MRI scans use a strong magnetic field and radio waves to produce two- or three-dimensional images.
The scans provide a significant amount of information that doctors use to diagnose MS and assess the status of people with the condition.
These scans can detect damage in the central nervous system, which comprises the brain and spinal cord. MS-related lesions appear on MRI images as either bright or dark spots, depending on the type of MRI scan.
This imaging technique is useful because it shows active inflammation and helps doctors determine the age of the lesions. Also, some specific types of lesions can indicate a flare-up of MS or damage in the brain.
It can be a good idea for anyone with MS to have periodic scans so that a doctor can assess the progression of the disease.
The frequency of scans will depend on a person’s disease course. For example, if a person’s MS is stable, they may only need periodic assessments, whereas someone with active MS needs more frequent scans.
There are two common types of MRI scans for the diagnosis of MS.
T1-weighted MRI scan
This provides information about the current status of MS. T1 scans
In a T1-weighted MRI scan, permanently damaged areas of the brain appear as dark spots or “black holes.”
The appearance of new or expanding lesions captured by a T1-weighted scan
T2-weighted MRI scan
This shows the number of old and new lesions in a specific part of the brain or spinal cord. It helps doctors determine the long-term impact of MS.
MS lesions appear as bright spots in a T2-weighted MRI scan. The appearance of more lesions on this type of scan may indicate higher levels of disability and a less favorable long-term outcome.
FLAIR sequencing
Fluid-attenuated inversion recovery (FLAIR) sequences are an advanced form of magnetic resonance imaging that can
FLAIR sequences suppress cerebral fluid from scan outputs, allowing for clearer imaging.
Gadolinium contrast
Doctors may inject a gadolinium contrast agent into a person’s blood before an imaging scan. These agents show up on imaging scans and can help to highlight MS lesions.
Brain atrophy and volume
MRI scans can also assess brain volume and brain atrophy
The way a lesion looks depends on the type of MRI scan. Lesions may look like bright spots or dark spots, and some brain lesions have darker outer edges that appear to expand.
Research has revealed certain lesions that are characteristic of MS.
Periventricular lesions are white matter lesions in direct contact with the brain’s lateral ventricles. The lateral ventricles are two large cavities that contain cerebrospinal fluid.
Doctors may refer to white matter lesions occurring perpendicular to the corpus callosum as Dawson’s finger lesions. The corpus callosum is a bundle of nerve fibers that connects the left and right brain hemispheres.
Juxtacortical lesions are in direct contact with the brain’s cortex. This is the outermost layer of the brain.
Doctors can also use MRI scans to assess central vein signs in specific lesions. Recent research shows MS lesions have an identifiable central vein, while other non-MS lesions do not.
The pictures below show what brain lesions may look like on an MRI scan.
Below are imaging scans showing brain lesions.
MS symptoms
| Area | Lesion symptoms |
|---|---|
| Cerebellum | impairment to balance and coordination |
| Optic nerve | vision problems |
| Spinal cord | muscle stiffness, numbness, tingling, pain, motor weakness, sensory deficits, bowel and bladder disruption |
Myelin sheaths cover the nerve fibers in the brain. Chronic inflammation from MS damages the myelin sheaths, which can result in brain lesions.
Currently, there is no cure for MS. Treatments can prevent or slow the progression of some types of MS and help manage symptoms. We explore some treatment options below.
Disease-modifying therapies
Disease-modifying therapies (DMTs) are an emerging type of medication that can help people with relapsing-remitting MS. They can reduce the number of relapses and help prevent or delay progression.
Current DMTs include:
- interferon beta-1a (Avonex, Rebif)
- interferon beta-1b (Betaseron, Extavia)
- glatiramer acetate (Copaxone, Glatopa)
- peginterferon beta-1a (Plegridy)
- teriflunomide (Aubagio)
- fingolimod (Gilenya)
- dimethyl fumarate (Tecfidera)
- cladribine (Mavenclad)
- siponimod (Mayzent)
- alemtuzumab (Lemtrada)
- ocrelizumab (Ocrevus)
- natalizumab (Tysabri)
Doctors must administer some of these drugs as injections or infusions, while people can take others by mouth. A person takes them whether or not their symptoms are flaring up.
Treatments for flares
Other approaches can help with pain and other symptoms.
- Corticosteroids: These reduce nerve inflammation. They are not a long-term solution, but they can relieve symptoms of severe relapses, including vision loss and severe weakness. Long-term use can cause side effects, including raised blood pressure, weight gain, and sleeping problems.
- Physical and other therapies: These can help a person stay mobile and active. In time, some people need help with daily tasks or benefit from using an assistive device, such as a wheelchair.
- Targeted symptom treatment: Various treatments can manage a range of issues, including urinary problems, sexual health problems, itchiness, and fatigue.
Plasma exchange
A plasma exchange, or plasmapheresis, involves removing and separating the liquid part of blood, known as plasma, from the blood cells.
A machine then mixes the blood cells with a protein solution and returns this to the body.
A doctor may recommend a plasma exchange when symptoms worsen or do not improve after treatment with corticosteroids.
Before an MRI scan, a person should eat and take their usual medications unless their doctor says otherwise. Inside the exam room, the person may need to change into a hospital gown.
It is important to remove any items that may affect the MRI machine, such as:
- eyeglasses
- hairpins
- watches
- jewelry
- dentures
- hearing aids
- wigs
- bras with underwires
MRI scans are not suitable in all cases. Doctors will not recommend MRI scans for anyone with the
- implantable cardiac devices, such as pacemakers
- implantable neurostimulation devices
- metallic fragments in their body
- metallic catheters
- cochlear and other ear implants
- magnetic dental implants
- drug infusion pumps
Before the scan, a healthcare professional may inject a chemical contrast dye, known as gadolinium, through an intravenous line into a vein in the person’s hand or arm. This improves the quality and accuracy of the images.
An MRI machine is a long, narrow tube. The person lies on a table that slides into the tube. A technician will monitor the examination process from a separate room.
During the scan, the inside of the machine makes loud, repetitive noises, such as tapping and thumping. The technician may provide earplugs or music to help block out the noise.
There is no cure for MS. On average, people with MS have a decreased life expectancy of around 7 years.
The severity and symptoms of MS vary from person to person, and symptoms can be unpredictable. A person can help manage their symptoms with stretching, light aerobic exercise, and dietary changes.
It is crucial to have a support network that understands what life with MS is like. Various organizations offer support groups and other resources.
In addition, MS Healthline is a free app that provides support through one-on-one conversations and live group discussions. A person can download the app for iPhone or Android.
Chronic inflammation from MS damages the myelin sheathes that cover nerves, causing lesions. These lesions can occur throughout the central nervous system, including the brain.
MS brain lesions can cause coordination problems, dizziness, slurred speech, muscular weakness, and sensation loss. The location of these lesions dictates which symptoms a person experiences.
There is no cure for MS, but several treatment modes can help people to manage the condition.