I think we're certainly dealing with a group of different disorders with similar symptoms. The current theory which I'm investigating for myself is as follows. I believe it affects some unknown percentage of CFS/ME patients.
CFS/ME for me is caused my IIH (idiopathic intracranial hypertension). This is increased pressure in the brain. The empty sella on my brain MRI is the first line of evidence.
"Idiopathic" just means the cause is unknown, not that no cause exists. IH is also alternatively called cerebrovascular hypertension (CVH), or the oversaturation of brain with blood. This has a number of potential causes:
Causes of IH:
1. Stenosis (narrowing) of the transverse sinus veins and/or the jugular veins, which drain blood from the brain.
2. TOS-CVH (Thoracic Outlet Syndrome - CVH) -- narrowing of the thoracic outlet below the collarbone and above the first rib. Potentially caused by very weak scalene muscles in the neck, which can be strength tested at home.
TOS-CVH causes blood which is supposed to go to the arm to be redirected to the brain, causing IH.
3. CCI/AAI - This is the one I know least about as I don't know how IH is related to this. But empty sella seems to be common in CCI/AAI patients.
1. Depends on what causes the stenosis. Various solutions are balloon venoplasty, stenting, transversectomy, styloidectomy, etc.
2. Conservative treatment by strengthening of the scalene muscle at home using exercises OR a scalenectomy, a surgical cutting of the scalene muscle.
3. Possibly fusion of C0-C2, but I don't know enough about this.
When it comes to me, I definitely don't have CCI/AAI, but I do definitely have TOS-CVH. I am trying to treat this conservatively at home, but it is proving difficult and painful. I am considering a scalenectomy.
Transverse sinus vein stenosis may also play a role in my case. I have to get that checked out this year with a catheter venography and manometry.