Spinal dural arteriovenous fistula typically occurs in men between the ages of 40 and 60 years with a progressive subacute clinical course.  The progressive myelopathy is related to venous congestion or arterial steal syndrome.

MR imaging findings of prominent vascular flow voids and numerous enhancing vessels suggest the diagnosis of arteriovenous malformation, which can be confirmed by spinal angiography. Cord expansion and T2 hyperintensity related to venous congestion and ischemia are common and may be associated with diffuse enhancement. Additional findings may be siderosis or intramedullary foci of T2-hypointense hemosiderin related to previous hemorrhage. Contrast-enhanced MR angiography is useful in identifying the level of the lesion and may facilitate spinal digital subtraction angiography, which remains the gold standard.