Presentation
Sudden onset of both lower limb numbness and paraparesis.
Patient Data
The lower spinal cord / conus medullaris appears swollen & edematous (cytotoxic edema / myelomalacia) associated with surrounding prominent serpiginous intradural extramedullary flow voids (dilated perimedullary vessels) extending down around the filum terminale. Heterogeneous low signal intensity on GRE images was also noted as suggestive of cord hemorrhage. Patchy intramedullary enhancement is also noted.
Findings are highly suggestive of spinal dural arterio-venous fistula/malformation.
Case Discussion
Spinal arteriovenous malformations (AVMs) are characterized by arteriovenous shunting with or without a true nidus, and includes both arteriovenous fistulae and arteriovenous malformations.
Spinal AVM's may be classified as intramedullary and extramedullary (80%).
An accurate diagnosis is important because these lesions may represent a reversible cause of myelopathy.
If a spinal vascular malformation is still suspected, digital subtraction angiography (DSA) must be performed to display the very small vessels of the spinal cord. Owing to the complications involved with DSA, an MRA or CTA can be used to determine the spinal cord level of the feeding artery and thus limit the amount of time it takes to perform the DSA procedure.
The present surgical treatment options include open surgical ligation or resection of the malformation, endovascular occlusion, spinal radiation, or a combination of these techniques.