Hi there are many reasons one could have hyper-tensities and neurological conditions are just one of the reasons and Chiari is a neurological condition.....
Since you stated that they were non specific I would imagine other possible reasons were ruled out.....
I had one Dr tell me that we can have these areas as a result of having painful headaches.....
May I ask what your Dr has said about this?
Well the radiology report said likely MS however both my neurpsurgeon and an MS specialist said that these hyper intensities did not follow an MS pattern. The neurologist basically said they were nonspecific could be migraine or from the RA, I do have a long history of frequent and very painful migraines!
Demylation is a possibility but since your Drs do not think so, then it is possibly a Chiari side effect.....
MS is unfortunately being DX'd more and more in those with Chiari.....so I would not dismiss it all together and find a specialist that is more experienced with MS just as you took time to locate a true Chiari specialist and have it rule out for sure.... and so you can relax.....if there is one thing I have learned dealing with my Chiari and all the related conditions I have is, not all conditions follow the same path and leave the same signals for us to follow...so when in doubt, ,get another opinion.
Keep us posted.