Have you thought of seeing a neuropthamologist? Sorry if you mentioned you did. I am not sure about the mri detecting what you are asking. For me I think they were looking for something pressing or a growth etc on the brain.
At least you are seeing a neurologist at Hopkins and I am thinking they could refer you to someone if the neurologist does not have answers.
On a side note you have sinus issues? From one eye doctor I was given nose spray because they thought and again a guess which starts happening when they can't figure out things. They said maybe the sinus was actually causing the eye pain but it did not and nose spray makes me so much worse.
Anyhow I will stop with my guessing for you. I hope you can find the true reason behind all this. Try to stay in the day which I know is hard. I remember when my eyes started I went from A to Z with so many fears but did the same with my legs and everything else. Ugh!
Sending warm thoughts

Quick update.

I went to the ophthalmologist yesterday about the double vision. He thinks the problem is from clotting...causing nerve damage to the extraocular muscles. I was having a problematic time (in excess of 15 in one month) with superficial venous thrombi when this double vision first occurred so I may have been having other clots elsewhere.

He does not think it will improve and may even get worse. He did say he might be able to help (i'll assume surgery) if it 'locks' into the double vision and doesn't resolve. Right now it occurs here & there during the day...more after eye strain (reading, watching a movie, etc).

Will be limiting eye strain to preserve strength...no more long internet/forum surfing. I'll do so in short intervals now.