From: Dural arteriovenous fistulas and headache features: an observational study
Barrow (for CCFs) | Cognard (for other DAVFs than CCFs) | ||
---|---|---|---|
A | Direct shunting of blood flow from the ICA into the cavernous sinus. | I | Normal anterograde flow into dural sinus |
IIa | Retrograde flow into dural venous sinus(es) | ||
B | Shunts to the cavernous sinus from branches of the ICA | IIb | Anterograde flow into dural venous sinus and retrograde filling of cortical vein(s) |
IIa + b | Retrograde drainage into sinus(es) and cortical vein(s) | ||
C | Shunts to the cavernous sinus from branches of the ECA | III | Direct drainage into cortical veins without venous ectasia |
IV | Direct drainage into cortical veins with venous ectasia (> 5 mm and 3 times larger than diameter of draining vein) | ||
D | Shunts from both the ICA and ECA simultaneously | V | Drainage to spinal perimedullary veins |