Sacral arteriovenous fistula with lower thoracic cord edema without perimedullary vein enlargement

Background: Sacral dural arteriovenous fistulas (AVFs) are often undiagnosed at the initial presentation due to their rarity. Case Description: For 1 year, a 71-year-old man developed progressive motor and sensory disturbances in both legs. Magnetic resonance imaging showed spinal cord edema with mild contrast enhancement T9–10 T12 levels. Although venous dilatation was observed only cauda equina level, it not initially recognized as abnormal. Blood cerebrospinal fluid tests angiography of lower thoracic upper lumbar levels were nonspecific. The patient unsuccessfully treated three courses high-dose intravenous methylprednisolone. Ultimately, following repeat (i.e., including bilateral internal iliac arteries) that revealed low-flow sacral AVF supplied by right lateral artery, underwent successful surgical occlusion/transection. Conclusion: In cases without perimedullary abnormal flow voids, careful spine is necessary even if minimal dilation level.