I have a mild Chiari malformation. If you're not having severe neurological symptoms, it's unlikely that the Chiari is causing problems. I was just diagnosed with it in August and spent 6 months ruling it out as the cause of my headaches and other neurological problems. Basically what's important is to make sure that the low-lying cerebellar tonsils don't impede cerebrospinal fluid flow. If they do, surgery can be done to restore the flow.
A lot of Chiari symptoms overlap with symptoms of other disorders. It's very important to keep a clear head and not try to blame Chiari for everything if it seems to fit. I did that. I was sure it was the problem because it explains so much. There's really a very small chance that it is the cause. I've been diagnosed with secondary Fibromyalgia, which covers many symptoms. I also decided to self-treat my hypothyroidism that my dr didn't think was necessary. I started taking desiccated thyroid, and within a few days, I felt TONS better. My daily headaches mostly went away after a week on the thyroid supplement too.
-Jenn. SAHM with 4 kids. Diagnosed with AS('08) Psoriasis, probable Sjogrens(won't do lip biopsy), Fibromyalgia, Chiari Malformation, PCOS, endometriosis, diabetes(type 1), metabolic syndrome, mild hypothyroidism...
Remicade & MTX.
*I am in no way associated with the medical profession other than doing my best to keep them in business. Any advice I give is purely my own opinion and should not be substituted for qualified professional care.