Most spinal fistulas are created when a radiculomeningeal artery feeds directly into a radicular vein near the spinal nerve root. Spinal dural AVFs are most commonly found in the thoracolumbar region. Patients become symptomatic because the AVF creates spinal cord venous congestion and hypertension, resulting in hypoperfusion, hypoxia, and edema of the spinal cord. Due to the slow-flow nature of most spinal dural AVFs, hemorrhage rarely occurs. Most dural AVFs are believed to occur spontaneously, but the exact etiology is still unknown. Again, these types of vascular lesions can be treated endovascularly with embolization using liquid embolics, such as Onyx and n-BCA, and with open surgery.