Deterioration after surgical treatment of spinal dural arteriovenous fistula associated with spinal perimedullary fistula.

Spinal dural arteriovenous fistulas (SDAVFs) are the most common type of vascular malformations of the spine and are defined as abnormal arteriovenous shunts within the dura. SDAVFs are considered to be acquired and should be distinguished from congenital intradural perimedullary arteriovenous fistulas (PMAVFs). A 32-year-old female presented with both SDAVF and PMAVF, manifesting as a slowly progressive paraparesis over a 6-month period.