Spinal dural arteriovenous fistulae (SDAVF) are rare but are still the most common type of spinal vascular malformation. Veins are low pressure and low flow structures, so when a fistula forms blood from an artery under a high pressure goes directly into a vein causing venous hypertension and congestion of the cord with edema resulting in cord expansion and T2 hyperintensity. The etiology is unknown. The best sequence to depict the extent of SDAVFs without using intravenous contrast agent is gradient-echo 3D ciss (constructive interference in steady state) sequences.