Hi...it is possible for u to have a CSF obstruction following a PFD due to scar tissue, not sure when or if u had a recent MRI....
Another issue could be that u have cerviocranial instability , making u feel like a bobble head, and it can cause many of the same symptoms.
Last, some chiarians develop ICP post op....increased intercranial hypertension. which would explain the LP's they did...no one seems to know why some develop this and not all of us.
May I ask were u dx'd with EDS b4 or after ur surgery? If so, did u have a dura plasty, and again is so what type?
I hope u join us for support in the Chiari forum here on MedHelp-