Surgical treatment of spinal dural arteriovenous fistulas

Increased understanding of the epidemiology, pathophysiology, and anatomy of vascular lesions affecting the spinal cord over the past 2 decades has permitted identification of subdivisions based on distinct biological features. The dural arteriovenous fistula (AVF) is the most common type of spinal vascular malformation and the most amenable to treatment. Venous congestion, the cause of myelopathy in these lesions, is effectively treated by interruption of the medullary vein as it enters the subarachnoid space between the dural nidus and the coronal venous plexus. Embolization of an untreated dural AVF in an acutely deteriorating patient stabilizes the neurological deficit and provides adequate time for definitive surgical treatment. The outcome after treatment of dural AVFs depends not only on the type and location of the lesion but also on the preoperative neurologic function. Patients who are ambulatory before treatment are usually ambulatory after treatment. Optimal outcome depends on early diagnosis and intervention.