I didn’t have VOO when I had my first surgery but my surgeon found my glossopharyngeal nerve was wrapped around my styloid & needed to be unwrapped so he could shorten the styloid. This caused half of my tongue to be paralyzed for 6-9 mos which made speaking clearly & eating normally somewhat challenging. I also ended up w/ a pretty gnarly case of First Bite Syndrome which I still have but it’s drastically reduced from what it was at onset.
I had some IH symptoms prior to my second surgery but they went away after my styloid was gone. I didn’t have a scan prior to surgery to see if I had vascular compression.