Endovascular treatment with Onyx of arterio-venous fistula around the transverse sinus presenting with ocular symptoms. Case report

Introduction: Dural arterio-venous fistulas /DAVF/ are rare vascular malformations that represent around 10-15% of all intracranial vascular malformations. The DAVF could be asymptomatic or produce a variety of symptoms - headache, pulsatile tinnitus, characteristic bruit over the site of the fistula, ocular symptoms - chemosis, proptosis, or other neurological symptoms due to intracerebral haemorrhage of the DAVF. We present a rare clinical case of a transverse sinus DAVF with ipsilateral ocular symptoms and maybe the first case to our knowledge occluded with Onyx with preservation of the transverse sinus. Clinical case: A 46-year-old male patient presented with headache, redness of the left eye and left-sided proptosis. The symptoms started after a heavy physical exertion two months ago. MRI scan and DSA confirmed the presence of a DAVF located around the left transverse sinus with venous ectasia and retrograde flow up to the left cavernous sinus. Transarterial endovascular embolization of the DAVF with Onyx was performed with complete resolution of the symptoms of the patient. Discussion: The more posteriorly located the DAVF the less likely is to present with ocular symptoms. Sometimes these are the first signs of the presence of a DAVF and especially of higher grade DAVF that could lead to intracerebral haemorrhage. The Borden Grade 2 and 3 DAVF risk of intracerebral haemorrhage is 17 % and 46 %, respectively. Cognard Grade IIa + b around 40 % and all grades III-V -80-100 %. The high risk of intracranial haemorrhage and the ocular symptoms are indication for treatment. Conclusion: Transarterial embolization of DAVF with Onyx is safe, with high initial occlusion rate (55-85%). Ocular symptoms of DAVF have a benign course after successful embolization.