Objective and importance: We describe a case of arteriovenous fistula in front of the sacrum. Drainage induced epidural venous dilation in the sacral spinal canal. The fistula was embolized endoarterially with n-butyl-2-cyanoacrylate via its iliac arterial feeders. In follow-up digital subtraction angiography 1 month later, the fistula was found to be totally closed. The patient was followed up clinically for 2.5 years. She has remained symptom-free.
Clinical presentation: A previously healthy 43-year-old woman presented with severe gluteal and perineal pain and a local sensation of hyperesthesia. The primary computed tomographic scan of the lumbosacral spine was normal, and emergency laparoscopy showed no signs of any pathological lesions. Magnetic resonance imaging discovered an unidentified mass in the sacral spinal canal, and the patient was hospitalized for neurosurgery. However, surgery on this mass had to be discontinued because of profuse bleeding, and the patient was referred for angiography.
Intervention: Diagnostic catheter angiography revealed a high-flow arteriovenous fistula anterior to the sacrum, and the mass detected earlier by magnetic resonance imaging seemed to be a dilated epidural vein draining the fistula. The feeders of the fistula originated in both internal iliac arteries, and the fistula was occluded via these arteries in two angiographic sessions.
Conclusion: A paraspinal arteriovenous fistula may have venous drainage through the epidural venous plexus, and the ectatic veins may induce radicular symptomology. To the best of our knowledge, a paraspinal fistula at such a presacral location has not been documented previously. An unidentified mass in the sacral spinal canal should be suspected of being a dilated vascular structure. Prompt angiographic examinations with an option for embolization should be performed, and open surgical intervention should be avoided.