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 vascular malformations of the spine, are usually supplied by branches of the intercostal or lumbar arteries. Rarely, the DAVF are fed by branches of the hypogastric artery. Only 12 such cases have been reported.

CASE REPORT: A 28 year-old man presented with a 2-month history of micturition 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 perineum. MRI of the lumbo-sacral spine demonstrated an enlargement of the conus medullaris with high T2 signal intramedullary lesion. It showed also large intradural serpentine vessels. A left iliac angiogram disclosed a nidus of arteriovenous malformation (AVM) supplied by a lateral sacral artery and draining by two enlarged ascending perimedullary veins. No clinical improvement 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 unusual arterial supply particularly from the hypogastric artery.