Hi, I'm sorry to know you're having hard time getting heard by medics with the right expertise to help with these horrible symptoms. Chiari malformations can indeed cause dizziness among other symptoms, but being a rare condition, unfortunately GPs are unlikely to know very much about it unless they have prior experience or a special interest in Chiari. As you
have been diagnosed with Chiari, I think you are right to request an up to date MRI, especially if your symptoms have changed since the last & if you can I would, as you suggest, see another Neurologist for a 2nd opinion. I'd try to find one whose interests include Chiari in adults though this may not be easy as it's my impression that most Neuros (at least in England) who treat Chiari patients are paediatric Neurologists as the condition is most often diagnosed in childhood. If you can't self-refer & go private & your GP needs convincing Chiari
can cause debilitating dizziness in order to refer you on the NHS, you could have a look for creditable sources of Chiari info online & print off what you find to show him/her. This is what the NHS website has to say but there are other reputable sites with more detail if you can bear to read them:-
https://www.nhs.uk/conditions/chiari-malformation/Menopause can also cause dizziness, as can various other conditions, but with a known Chiari malformation I would want further Neuro advice given your symptoms. Please PM me if you want more info - I'm not on the forum much these days.
W x