Table 1.

Classifications of intracranial dural arteriovenous fistulas

Type	Description
Type I	Drainage into a sinus without flow restriction
Type II	Drainage into a sinus with flow restriction and reflux into other sinuses or into cortical veins
Type III	Drainage into a cortical vein
Type IV	Drainage into a cortical vein with a large varix
Type V	Spinous perimedullary venous drainage

Adapted from: [7].