Spinal Dural Arteriovenous Fistulae

Abstract

As opposed to the so-called congenital arteriovenous malformations (AVMs) involving cord and paraspinal structures, spinal dural arteriovenous fistulae (SDAVFs) are acquired shunts located within or adjacent to dura along the spinal canal. They are by far the most frequent arteriovenous shunt (AVS) that occurs in older adults. They usually present after the fourth or fifth decade of life, with an 85% (5:1) male predominance (Tables 12.1, 12.2).The reason for this male predominance at the spinal level is not known,and this dominance is reversed in dural and osteodural AVSs at the skull base and sphenoid level, where there is a female pre-dominance. The location of the fistula has been reported throughout the spinal canal, from the sacrum to the level of the foramen magnum. The venous drainage may be very extensive and reach the intracranial dural sinuses even if the shunt is at the sacral level (Fig. 12.1) or conversely reach the thoracic perimedullary venous plexus level from an intracranial shunt.