Living with MS
Lesion
What it is
A lesion is a patch of nerve damage in the brain or spinal cord that shows up on an MRI. In MS, lesions are spots where the protective coating around nerves has been inflamed or injured. Some lesions are active and some are older and stable.
Why it matters for you
You will see this word in MRI reports and hear it in appointments. Understanding that a lesion is a specific finding on a scan, not a verdict on your future, can make those reports easier to read.
Questions to ask your doctor
- How many new or enlarging lesions are there?
- Is there any enhancing (active) activity?
- How does this compare to my last scan?
- What areas of the brain or spine are affected?
- Does this change my treatment plan?
Frequently asked
Does a new lesion mean my MS is getting worse?
Not always. Some new lesions are silent and do not cause noticeable symptoms. Your neurologist weighs new lesions together with how you feel and whether you are on an effective DMT.
What is an "enhancing" lesion?
An enhancing lesion lights up on an MRI with gadolinium contrast, which usually means it is currently inflamed. Non-enhancing lesions are typically older and stable.
Find MS treatment centers near you
MS care is specialized — the center you choose shapes access to DMTs, infusions, and clinical trials. Pick your state to see centers in your area.
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Reviewed by the MS Buddy editorial team · Last updated April 16, 2026
Not medical advice. Always consult your care team.
Not medical advice. Always consult your care team.