How MRI's Show MS Lesions

[Quixotic1]

MY QUICK AND DIRTY EXPLANATION OF HOW MRI'S SHOW LESIONS IN MS

I am going to overexplain the MRI with contrast / without contrast thing again, so that you and your husband can have it as clear as possible in your minds.

MS does it's damage by causing the nerves in localized areas in the brain and spinal cord to lose their protective sheaths, called myelin.  At first, when the myelin is being attacked, the body brings a higher blood supply to the area to fight the attack and the area becomes inflamed.  These areas, now become lesions.  At this point they are called "active lesions."   At first the nerves haven't changed much and they appear (and have the same density) as the healthy areas around them.  At this point after some time, probably months, the body CAN repair the damage and remyelinate the nerve.  This repaired nerve still won't be as good as new, but the lesion "looks" like normal brain.  Sometimes later an old scarred lesion will "reactivate" and the adjacent areas will inflame and have increased blood flow.

If the attack on the myelin sheath is too strong for the immune system to repair, more and more myelin disappears and the area of nerves eventually dies.  Then it contracts and scars.  The blood flow is decreased to that area and the area becomes "less dense" then the surrounding normal nerve tissue.  After a longer time - probably years - the scar can reabsorb and the area becomes "empty."  It's called a black hole.

When you image these lesions with an MRI you can see different things, depending on the technique,the age (stage) of the lesion, the power of the MRI, and whether contrast is used.

The first image is done without contrast.  This technique will show old lesions that are big enough to be seen by the power of that MRI machine.  WE KNOW that many lesions in MS are too small to be seen.  If the newer, more powerful MRI with a 3 Tesla magnet is used many more lesions will be seen (by at least 25%) than on the older 1.5 Tesla machines.  The classic old, mature MS lesion is a little bit oval, will have well-defined borders and will be in the white matter.  Characteristic places are subcortical, peri-ventricular and in the corpus callosum.  The classic MS lesion will also have it's long axis perpendicular to the ventricles of the brain.  Also, important and very symptomatic lesions are found in the brainstem, the cervical and the thoracic spine.  The spinal cord ends at the bottom of the thoracic spine, so there is no such thing as a lumbar spinal cord lesion in the normal spine.

These scarred lesions will show up as light, bright areas.  These are the classic, MS lesions or "plaques."

Now the very old, scarred ones that have been reabsorbed will show up as a black (empty) space or black hole.  If there are many of these empty areas the brain will contract around them eventually and show up as a loss of brain volume.  This is also know as brain atrophy.  This is particularly seen in the progressive types of MS.

However, a newly active MS lesion may not show up on a regular MRI because the area of nerves, though inflamed, is still pretty much intact and has normal brain density.  On the MRI it will look like normal brain.  Without contrast it won't show up and will be missed.

When the next phase of MRI is done the contrast is in the blood vessels.  So the large blood vessels show up, too.   Anywhere the tiny blood blood vessels are more dilated than usual, as in inlfammation, the areas will "highlight"  or "enhance."  They show up as even brighter.  So new lesions will show up as enhancing, or active.  Also, older lesions, that have undergone new attack right around them will show an enhancing rim or ring.  When you compare the regular MRI to the Contrast MRI you can see this reactivated, old lesion.

That's how some reports can call active lesions or some report no newly enhancing lesions.  Also since some new ones heal they can be compared to old films and show they disappeared.  In addition, between different sets of MRI done after a time has passed, the radiologist can see an increase in old and in new activity.

Please ask question where I haven't been clear.

Quix

[COBOB]

MRI is only one part of an MS diagnosis.  Some docs insist on the MRI.  If you still have symptoms, forget about the old diagnosis or what was or wasn't on the MRI.  Goto a neurologist and have them check your symptoms and signs.  

Bob

[woozy16]

Hi all,

After 5yrs of all kinds of funky symptoms, a diognosis of Fibromyalgia and arthritis. As you can imagion i am fed up.

4yrs ago i was tested for MS and after an MRI was told the symptoms were in my head and that i was depressed (if only)
Last week i was told all previous diognosises are wrong and need to be seen by a nero specialist AGAIN!.. as i have lost all reflexes in my feet, ankles and knees. and have no sensation up to my thighs. I am confussed finding it harder and harder to walk and have been told i am drunk many times. I have developed a squint, blurred vision and been told my eye twitches what ever that means.

am wondering if 4yrs on am i wasting my time trying to get the right diognosis or just give up and try to get on with life the best i can?

[Sparkysarah]

Hi there Kymmemar

I would suggest that you copy and paste your post into a new one. Many people will fnd it difficult to read a block of text in capitals and willl be unable to respond as they can't read it all. I never even realised this myself until I read other people's comments and realised that it applied to myself.

If  you break your writing up into smaller shorter paragraphs this will help everyone to read it more easily, and especially Quix who gets a lot of posts to digest and respond to.

Best wishes

Sarah

[KYMMEMAR]

HI, I AM NEW TO THIS AND WOULD VALUE ANY INSIGHT.  I AM 45 YR, WHITE FEMALE, RN, WHO WAS DIAGNOSED WITH GRAVES DX 3 YRS AGO.  I HAVE HAD INTERMITTENT LEG WEAKNESS DURING AND AFTER GRAVES TX.  I HAVE BEEN ON PREDNISONE THERAPY THROUGHOUT THE LAST YEAR DUE TO ASTHMA EXACERBATIONS.  10 MOS AGO I FOUND I WAS UNABLE TO WALK UPSTAIRS WITHOUT LEANING AGAINST THE WALL, INSOMNIA, DIFFICULTY GETTING OUT OF A CHAIR, SOME FORGETFULLNESS AND FATIGUE.    I FOLLOWED UP WITH ENDOCRINOLOGIST WHO DID LABS AND THYROID WAS GOOD BUT ANA WAS 1:320 SPECKLED.  I NEXT WENT TO RHEUMATOLOGIST FOR LUPUS TESTING.  ALL LABS NORMAL EXCEPT ANA 1:160 SPECKLED AND HOMOGENOUS. NOW I HAD INCREASING LOWER BACK PAIN .  PCP DID XRAY AND SHOWED SIGNIFICANT COLLAPSED VERTEBRAE IN LUMBAR. FOLLOWUP WITH NEW  RHEUMATOLOGIST 2 DAYS LATER. RHEUMATOLOGIST SAID NO "COLLAGEN DISEASE" AND DID LUMBAR MRI - SHOWED NO COMPRESSION AND SHOWED NO REASON FOR MY INABILITY TO CLIMB STAIRS OR INCLINES.   REFERRED TO NEURO.  NEURO CHECKED FOR MYASTHENIA GRAVIS, ALL NORMAL LABS/TESTS.  I NOTICED AN AREA OF NUMBNESS ON MID BACK LEVEL - MRI OF THORACIC WAS DONE AND ESSENTIALLY NORMAL.  -- SOME MEDIASTINAL CYSTS FOUND OF UNKNOWN SIGNIFICANCE.  NEXT  NEURO APPT TO DISCUSS TESTS AND HE STATED THAT IT WASNT MYASTHENIA GRAVIS & NO NEED FOR MRI OF HEAD, AS I SUGGESTED,  BECAUSE HE DIDNT THINK IT IS MS. ---ALTHOUGH, MY LEG MUSCLES FEEL LOCKED UP AND VERY TIGHT AND MY RIGHT LEG DRAGS WHEN WALKING.   I CANNOT WALK NORMAL FROM LEFT AND THEN TO THE RIGHT LEG.  I HAVE HAD SOME TINGLING WHEN WALKING AND FEELINGS OF WARM WATER SPLASHING ONTO CALF.  TODAY DURING HIS LIMITED NEURO EXAM, 2ND VISIT,  MY ARMS/HANDS WERE SHAKING AND MY LEG COULD NOT MOVE ONTO SHIN OF OTHER LEG. NEURO DOC SAYS HE IS SENDING ME BACK TO PCP  BECAUSE HIS MYASTHENIA GRAVIS TESTS WERE NORMAL AND ASKED IF I FELT OVERLY STRESSED.      HE DID STATE THAT HE WOULD ORDER THE MRI OF HEAD IF I WANTED IT.   PLEASE HELP!  I FEEL LIKE THIS DOC JUST BASICALLY SHOVED ME AWAY.  DO I PROCEED WITH MRI AND PCP FOLLOW UP.   THANKS FOR LISTENING, KYMME

[ktbell]

I NEED SERIOUS HELP. I AM 41 YEARS OLD SUFFERING FROM EXTREME FATIGUE,FEELING LIKE SOMETHING CRAWLING OUT FROM UNDERNEATH MY SKIN ON BOTH ARMS AT DIFFERENT TIMES, ACHY BODY LIKE FLU, LOW GRADE TEMP MOSTLY AT NIGHT, JERKY EYE TWITCH,UNABLE TO REALLY TASTE OR SMELL ANYTHING, NO SEX DRIVE, ON AND ON. BEEN TO SEVERAL DOCTORS WITH MOST OF THEM SAYING THAT IT IS FIBROMYALGIA. TESTED NEGATIVE FOR LUPUS. CANNOT FIND ANYONE WHO WILL LISTEN TO ME. HELP!!!

[Quixotic1]

Hi!  Welcome to the Forum!  Have you been reading here long?  You landed on a very old version of the MRI and lesions discussion.  the one in the Health Pages (upper right hand corner) is better.  I looked at your profile and you have an amazing number of things going on.  Would you be willing to start a new discussion and tell us about yourself?

As you know we can't diagnosis anything online - there just isn't enough info.  But, I can talk about things in the context of MS and I will answer your question.  IF the neuro (whom you don't like) was considering MS when he did the spinal tap, then he was wrong to tell you that MS was ruled out because the fluid was normal.  A normal spinal tap (especially 2 years ago) does not mean that you don't have MS.  There is NO requirement for the tap to be positive in order to diagnose MS.  In fact, there is no requirement EVEN TO DO A TAP in order to diagnose MS.  In Europe they do not use the spinal tap routinely at all.

Now the lesions could be many things.  But you should have someone tell you what they likely mean before you can just dismiss them.  I would encourage you to seek out a new neurologist.  Why was the MRI done?  What problems and symptoms have you had?

But, we would like to know more about you.  From your profile I see that you must have a very complicated medical past and see that you are on oxygen.  If you would start a new thread - just go to the top of this page and click on "Post a Question."  Your post will be lost here and people won't see you.

Welcome again, quix