Am I right that optic neuritis is more common early in the m.s. process and less common later? That it "burns out" and ceases to be a problem for some?
The studies which I have read say that optic neuritis is a symptom found in early MS. I will try to locate a study which says that in some instances the optic neuritis is the only symptom and therefore the patient is considered benign MS. I have never had optic neuritis -- in fact, at my last eye appointment, my doctor said the optic nerve shows no damage at all. He said this was quite unusual for someone with MS.
Now about your medical question
Is this because of the widening of the ventricular area in the brain, as m.s/ccsvi progresses, so then there is a place for the backwashed blood to go?
I have no clue - I would think this is something that wil be researched in relation to CCSVI -- so many "truths" or "theories" are going to be re-researched in the future.
Going to NYC and being able to attend the talk and then meet Dr. Zamboni ---- it was an adventure --- an exciting experience.