Hi and welcome to the Chiari forum.
There r many NS and Nl's out there that r not up on the most current ways to treat and dx chiari...they go by the out dated info that the herniation mandates if it is chiari or not and it must be a 5 mm herniation..the facts r the size of the herniation r not as important as whether or not u have a CSF obstruction and overcrowding..chiari is the malformation of the skull and not the herniation as many believe and go by.
What the drs that do not work with chiari daily do not realize is that even tonsils that do not go beyond 2mm in herniation can cause much more pain and issues than one that is 13mm's in herniation....it is more the width not the length that can cork up the opening.
Family history itself is a huge red flag, but with inexperienced drs, it doesn't matter if it was neon....u need a dr that knows chiari and chiari related conditions. I would imagine u have copies of all ur MRI's to date...and the only one u did not mention was a CINE MRI..that is the flow study....
Next u will want to rule out conditions with similar symptoms like MS, Lupus, Lymes,,,,etc...and then look at related conditions as u have already started with syringomyelia, tethered cord, sleep apnea, ICP,Ehlers-Danlos,retroflexed odontoid and disk issues.
The list of Drs we compiled here of the members drs, is here to help u research drs, and is not meant as a referral- u need to find the dr that is right for u.---
http://www.medhelp.org/health_pages/Neurological%20Disorders/DOCTORS-LIST-FOR-CHIARI-SYRINGOMYELIA/show/1062?cid=186
"selma"