Causes of ON

Hello, after having a series of symptoms starting in September including left eyeball pain and a series of MS symptoms I went to see a neuro. The first MRI of the head came back negative for mS but showed some sinusitis, and the second one of teh optic nerve area shows optic neuritis. I was under the assumption that ON is a precursor for MS or a sympotoms but the neuro's office has told me that it's not Ms and to just follow up with my GP and perhaps an eye doctor. I saw my eye doctor when this all began, and I did post about the vision test and the tests they did. At that time I was told no ON, but the MRI that I had a month later shown ON. Can you explain that to me please and in your opinion as a eye specialist, what could be causing this ON if not MS?? And should I expect to have this ON again??  I just feel liek I've been left in the dark here. First told clinical MS and now told no need to come back, just ON. I had three episodes of this ON, each coming at the same time of my mensus. is that common?? Thank you for your time.

[Forum-OD-MP]

okay MS is *one* of the many things that can cause ON.  lots of systemic diseases/problems can cause optic neuritis.  ON is really just inflammation of the optic nerve or optic nerve head.  it could be caused by anything.  just b/c you have ON certainly does not automatically mean you have MS.  some people get ON and have NO systemic problems.  they just get it b/c they're unlucky (we call this "idiopathic").  or maybe its a precursor to something sometimes.

BUT!  many people with MS develop ON.  thats why when we see ON, we think possible MS.  but the neurologists see MS *all the time*.  if they looked at your MRI and said you did NOT have MS, then you most likely do not.

optic neuritis usually manefests itself as pain and/or POOR VISION.  if you have *good* vision, and NO pain, ON is pretty unlikely IMO, no matter what the mri showed.  (i said unlikely not impossible...just to cover myself)  especially if you went & had an eye exam and the eye doc said you are fine.  ON has a certain pretty unmistakable appearance.

so what are you seeing on the mri?  who knows?  could be something like optic nerve astrocytis hamartoma (a benign tumor of the optic nerve) or something weird.

if you continue to have good vision and no eye pain, and your eye doctors and neurologists keep saying you are fine, then dont worry too much about what the mri shows.

as for ON being related to your menstral cycle...dont know.  havent heard of that one.

[Ag-i-doc]

just looked up ON in some of my books, and the #1 cause of ON is "idiopathic", meaning no one knows.

#2 cause is MS