Some doctors who do surgery for vES w/ IJV compression in the US prescribe a blood thinner for their patients w/ IJV compression to take during the time they’re waiting for surgery. For some people it practically takes away the brain fog & headaches but for others it doesn’t work as well. The blood thinners most often prescribed in the US are Plavix, Brillinta, & Xarelto. A blood thinner can take up to a month before it produces noticeable help w/ symptoms so taking it for at least that long is necessary. If it works, then it can be taken more long term up till a couple of weeks before surgery.
I believe Prof. Marres does his surgeries through the neck & even a styloid that can be felt in the throat is most successfully removed through the neck. Neck pain is a normal ES symptom, & the feeling of your head being heavy seems to be more related to the intracranial hypertension that occurs w/ IJV compression so it is also somewhat normal for vES patients.
Here is a link to a discussion where Dr. Marres is mentioned. It may be helpful for you to read it: Neck and back pain - #4 by Dodo
I’m sorry you’re having such terrible symptoms while trying to finish school. I can imagine that is terribly difficult. I hope you’re able to get an appointment w/ Prof Marres so you can be accurately diagnosed & receive the best possible treatment.