[Intracranial dural arteriovenous fistula with spinal venous drainage]

Two cases of intracranial dural arteriovenous fistulae draining into the medullary veins are reported. One patient was a 68-year old man who experienced brief and repeated episodes of paraplegia, followed by a permanent spinal cord syndrome. The other patient was a 74-year-old woman who rapidly developed a syndrome of the medulla and spinal cord. In both cases spinal cord angiography failed to show vascular malformations, but myelography revealed venous imprints and magnetic resonance imaging of the cervical spinal cord disclosed a pre-medullary signal. Cerebral angiography showed an intracranial arteriovenous fistula fed by the external carotid artery and draining into the veins of the posterior fossa and the spinal venous network. Complete occlusion of the fistula was achieved by embolization with microparticles. Intracranial dural arteriovenous fistulae draining into the medullary veins are rare: to our knowledge, only 4 cases have been reported. Such lesions must be considered whenever a spinal cord syndrome has no detectable cause.