AB137. SOH24AB₁14. A rare presentation of a sacral dural arteriovenous fistula: a case report

Background: Sacral dural arteriovenous fistulas (DAVF) are rare presentations and are often undiagnosed. They most commonly affect the thoracolumbar region, consisting of a pathological communication between arterial and venous vessels in the spinal dural sheath, which gives rise to symptoms similar to those of other spinal cord disorders. Case Description: A 72-year-old gentleman presented with a 6-month history of lower back pain and a rapid progression of lower limb weakness, along with a reduction in bladder and bowel function. His past medical history was significant for hypertension, atrial fibrillation and hyperlipidaemia. Significant findings on examination included increased tone and hyperreflexia in the lower limbs, along with a positive Babinski sign bilaterally. He also had a post-void residual volume of 350 mL. Neurosurgical intervention was carried out with a transpedicular T5/6 discectomy. Symptoms improved for weeks before rapidly deteriorating. Intramuscular corticosteroid injections worsened the patient's symptoms. Magnetic resonance angiography (MRA) revealed a DAVF from T9–12. Spinal angiography revealed a right sacral DAVF at the level of S5, which was treated by embolization. The patient's lower limb weakness subsequently resolved and he was able to mobilise with a rollator. Conclusions: Diagnosis of a sacral DAVF is complicated due to its presentation with non-specific progressive spinal cord symptoms, as portrayed by this case. MRA imaging is therefore an important investigation for this condition as it can prevent delays in management. Treatment options include endovascular embolization or surgical ligation of the fistula, both of which have proven to be effective.