I remember reading a post on the FB Jugular Venous Outflow Disorders group about Dr Mehta updating his venogram protocol to not use sedation in patients where it’s suspected that soft tissue is likely involved in the IJV compression. This was as a consequence of one patient showing different pressure gradients on two venograms done using different sedatives. I did not end up talking with Dr Mehta about this, I just asked his assistant whether it would be possible to have it without, he relayed it to him and came back to say that it’s fine and we’ll do it without, so I’m not super sure about his current stance on the issue.
I just wanted to add a word of caution about going without sedation. I don’t regret doing it, and if I were to do the whole thing again, I would still choose to go without. My reasoning was that if there is even a small chance of a false negative, which could delay getting treatment, maybe indefinitely, the cost of one hour of discomfort is negligible by comparison.
That being said, it was fairly uncomfortable. Not pain-wise, but in terms of the unnatural sensations I went through. The venogram part is fine, as the contrast dye (which is an irritant) is injected into the veins, and it quickly makes its way away from any sensitive tissue. During the angiogram, however, since the dye is injected high in your carotid artery, a high concentration of it reaches the tissues in your head. The dye cannot cross the blood-brain barrier, so your cognition isn’t affected. However, since extracranial nerves are not protected the same way, they feel the brunt of it. For me, this meant burning sensations inside my mouth and head, my hearing got muffled at some point, I got dizzy, I saw lightning flashing, and my eye muscles stopped working, meaning that my affected eye stopped focusing correctly, all on the side where the contrast is injected (they inject it twice on each side of the head). Although I had been prepared for this by the nurse, and rationally I understood these were normal, transitory sensations (they never lasted more than a 10-20 seconds), my lizard brain really freaked out, and I had to try hard to calm myself.
My advice here is to talk to Dr Mehta about going without sedation. If, however, you also feel strongly about going without, I really recommend trying to keep your eyes closed during the procedure. The vision issues thing was maybe the most unnerving, and I think I could have avoided that had I not been trying to follow the images they were getting (you can see the monitor in real time during the procedure).