Sacral meningeal arteriovenous fistula supplied by branches of the hypogastric artery revealed by conus medullaris infarction

Objective: Spinal dural arteriovenous fistulas (DAVF), the most common vasc ular malformations of the spine, are usually supplied by branches of the in tercostal or lumbar arteries. Rarely, the DAVF are fed by branches of the h ypogastric artery. Only 12 such cases have been reported. Case report: A 28 year-old man presented with a 2-month history of micturit ion dysfunction and progressive weakness of the legs. Physical examination showed motor deficit of the lower limbs with brisk knee jerks, absent ankle reflexes and normal plantar reflexes. Cremasteric reflexes were absent. We noted hypoesthesia of the lower limbs with complete anesthesia of the peri neum. MRI of the lumbo-sacral spine demonstrated an enlargement of the conu s medullaris with high T2 signal intramedullary lesion. It showed also larg e intradural serpentine vessels. A left iliac angiogram disclosed a nidus o f arteriovenous malformation (AVM) supplied by a lateral sacral artery and draining by two enlarged ascending perimedullary veins. No clinical improve ment was observed after surgical removal of the AVM. Conclusion: The screening examination of choice for spinal DAVF remains MRI . When selective spinal arteriography is normal, we have to search for an u nusual arterial supply particularly from the hypogastric artery.