I assume your neuro’s reason for requesting the MRI was to assess how active the disease is currently? In that case, contrast is really the only way to distinguish between active and historic lesions, and so to get a snapshot of how active the disease is today. If that was his reason for wanting the information, he wouldn’t get it without the contrast, so that might be why he decided it’s not worth bothering.
On the subject of the risks of contrast, like you I’d read a few horror stories. But from what I can gather, severe side-effects are extremely rare. I don’t think I’ve ever read a post here from anyone who experienced a serious side-effect.
I was really nervous about mine, but other than the general unpleasantness of having intravenous anything, all I felt was a coldness at the injection site as the contrast actually went in.
The hospital (a private one) were not happy about me leaving the premises until I’d sat down for ten minutes and had a cup of tea - just in case of any delayed reaction - I felt absolutely fine, and was all for leaving ASAP, but reluctantly agreed to sit and have the tea, which I felt was over-cautious.
They do recommend you drink plenty afterwards, just to flush it through, so having tea made sure I’d got off to a good start, as well as giving them ten minutes extra observation time to make sure nothing was amiss.
I didn’t have a headache, or a site reaction, or anything.