CD, I don't know. I thought the eye was drained by veins that drained into the internal jugulars. The emissary veins are tiny veins that contribute to the drainage of the venous dural sinuses. Emissary veins actually travel through the skull in little canals just for them, from what I understand. When I looked them up yesterday, I found some discussion that trauma can sever these emissary veins. Aha! I thought. Here is another explanation for patients who associate trauma with incipient MS symptoms.
Then I read that the severing of emissary veins leads to subdural hematoma, which is very serious and noticeable and can be fatal. So I took down a post I made here about it, actually.
Then I gave it more thought and I think, if these veins can be severed during trauma, they can also probably be injured to any degree up to the point of severing. So head trauma could cause these emissary veins to be damaged, but not altogether severed, which would lead to the blockage of these veins as a cerebrospinal route, which could worsen CCSVI, although I think these veins are too small to be contributing much to the flow.
There is also the earlier information that trauma to the head can cause shearing of neurons, which would worsen a condition that was perhaps borderline or subclinical MS, thus bringing it out into the open.
And since most people have a car accident or a bump to the head in their personal history, it could just be a coincidence of timing or a tendency of humans to attribute causality to randomness.
I am glad I have a whole thread of my own, it is good for rambles.