A few questions about active demylination and dilated pupils.

[Nickie72]

Although I've read the helpful links on MS and lesions, I was unable to find a few answers to my questions, and I went to Google as well. So, hopefully someone can help me learn a bit more? My latest MRI was on Friday, and it reads that I have abnormal enhancement associated with a small lesion in the subcortical medial left parietal lobe compatible with active demylination.

I know that the lesion is inflamed and blood engorged, but what happens after that? Was it due from my last flare-up, or does it mean that I'm gonna have another flare-up soon? Could I be having a flare-up now and that's why? I really don't think I am because my fatigue usually gets 10 times worse when I have a flare.

Another question: Does anyone have a pupil bigger than the other that HASN'T had ON? I've had this for the past year in a half and my daughter pointed it out to me and it's never gone away. In fact, it's a bit bigger than it used to be and very noticeable, and my Opthamologist mentioned something about glial cells, but didn't think I had ON or ever did. I made another appt to be on the safe side, although my evoked potentials came up fine a while back.

Thanks for any help and much love to all! :)

[illinwithoutacause]

hi,

i am as of yet undiagnosed, with a recent c-spine MRI revealing possible myelitis on the anterior cord.

my left pupil has been significantly smaller than the right for about 6 months, but i have not had an episode of ON.  i have had 2 thorough neuro-ophtho exams and my doc noted optic nerve vasculitis, but no actual inflammation of the optic nerves themselves.

i have also had both pupils dilate spontaneously which was incredibly painful.

just wanted to add my experience.

best wishes,
binx

[Deb61]

It sounds pretty suspicious for ON to me because of not only your eye symptoms, but from your other symptoms.  I didn't notice the color difference either until I had to cover one eye.  As you probably have found in research, optic neuritis is not always visible upon exam or even an MRI at times.  It is also possible to not have much blurriness with optic neuritis.  

I'm glad you fired this ophthalmologist.  Another one will give you a fresh new opinion.  

Deb

[Nickie72]

Hi roxthexl! I totally worded my beginning post wrong. My apologies. I wish we could edit our first post, because not always do I proofread and I should. My dilated pupil DOES go away but to only return, and I always wondered why. It could be in a few days or a week but it's HUGE when it happens. Today is another one of those days where it's dilated again and I think it's the strangest thing.

I never read the compete details about Optic Neuritis until last night, when I went to mayoclinic *******, and I never knew this: "Loss of color vision. Optic neuritis often affects the perception of colors. You may notice that the colors of objects, particularly red ones, temporarily appear "washed out" or less vivid than normal."

I went to my first MS Specialist on Friday and I mentioned my dilated pupil and he studied my eyes a bit. He also told me to cover one eye then the other, and put a bight red glossy notebook in front of my face. He asked me if I noticed any difference when I looked at the notebook and here are my exact words: "Maybe I'm studying too hard, but as I look at it out of my right eye, it doesn't look as bright and glossy as the left eye. It looks kinda pale colored." So, yeah, I fipped a little inside when I read the mayoclinic info, in fear it's on its way.

I ended up firing my Ophthalmologist because I received no phone call of cancellation on the day of my appt. We didn't even get 2 inches of snow, and all the people in the office got scared and left for the day. I lost a lot muscle mass in my legs and I'm walking with a cane and have excruciating pain, and it seemed to take hours to get myself out the door, including the lack motivation caused by depression... so the doc got a really nasty message from me and boy did it feel good! :)

[rothexl]

I just saw your question- what I can add is that I was found to have ON (via MRI and delayed pupil reaction) but did not have any symptoms at all. I had one day where I had some pain, but no visual loss at all. And a lot of the time my right pupil is larger than the left, then both will be normal again for a day, then it happens again etc.
However this started happening only now during a flareup-and changes constantly-, so if your pupil has been larger constantly for over a year I don't know if that can still be ON- definitely have this checked out-- and maybe have an MRI with a special protocol to image the optical nerves. All the best, Rike

[Nickie72]

Hi, Deb, and thanks for stopping by with the link. I was reading about this on many other sites as well, but wanted to see if anyone had one dilated pupil that have never been diagnosed with ON.

Apparently, from what I read late last night, many people can get a very light case of ON and not even know it, and because of this reason, some people get the dilated pupil in that effected eye. It does sound a bit strange.

[Deb61]

I had difference in pupil size when I had ON.  There's other causes like glaucoma, problems in the brainstem.  There's a Medhelp post that addresses this issue:

http://www.medhelp.org/posts/Neurology/Varying-Pupil-Size/show/896256

[Nickie72]

This is what I found and it's very interesting:

Demyelination is the major underlying factor responsible for the symptoms of multiple sclerosis (MS). Demyelination is the destructive removal of myelin, an insulating and protective fatty protein which sheaths nerve cells (neurons). More specifically, the myelin is wrapped around the long extensions of neurons called axons. During MS relapses, patches of white matter in the central nervous system that normally contain tracts of myelinated neurons become inflamed and lose their myelin. These patches of demyelination are known as lesions.

The cause and precise mechanism of demyelination is not clearly understood but there is good evidence that the body's own immune system is at least partially responsible. Acquired immune system cells called T-cells are known to be present at the site of lesions. Other immune system cells called macrophages (and possibly mast cells as well) also contribute to the damage.

Myelin is produced by special "glial cells" in the central nervous system called oligodendrocytes. Oligodendrocytes and axons have a many to many relationship - that is one oligodendrocyte produces myelin for several axons and one axon has several oligodendrocytes producing its myelin. In MS, it is not just the myelin that is destroyed but also these oligodendrocytes and occasionally even the axons themselves.

Axons use an electrochemical mechanism to transmit nerve impulses - the action potential. This requires sodium and potassium ions to pass through a semi-permeable membrane around the nerve. It is believed that the myelin not only insulates and encases this electrochemical process but also actively assists it. When axons become demyelinated, they transmit the nerve impulses 10 times slower than normal myelinated ones.

During periods of MS remission, the oligodendrocytes repair the damaged axons in a process called remyelination. However, very often the oligodendrocytes are also destroyed which delays or prevents remyelination from happening. Additionally, another kind of glial cell, called astrocytes, cause scar tissue to form in place of the myelin. Scar tissue does not perform the same function as the myelin. As the disease reaches its more advanced phases, the axons themselves are often destroyed as well.

http://www.mult-sclerosis.org/demyelination.html

So, what this tells me is that I was in the middle of a flare up at the time of the MRI. If I am mistaken, maybe someone else can clear this up for me.

[Wobbly]

Hi there.. sorry I can't give you any answers and I think your Neuro will have to answer these questions.. when to do you see your dr again?  You have good questions and I'd like to know the answers too

maybe someone else with more knowledge will jump in and answer for you.

take care
wobbly
dx

[cali1892]

Forgot to say I was not on any medication at the time.

[cali1892]

Hi,
I don't know the answers to your questions.  But, I'm interested in other's answers.  I have had both pupils dilate and stay dilated for days.  I don't recall feeling particularly bad at the time though.