[Peripheral facial palsy after embolization of a dural arteriovenous fistula with Onyx®]

Dural arteriovenous fistulas (DAVF) are intracranial vascular malformations which can cause severe complications, such as intracranial bleeding and neurological deficits. We report the case of a patient presenting with pulsatile tinnitus caused by a DAVF. The DAVF was endovascularly treated including transarterial embolization with the liquid embolic agent Onyx®. The fistula and tinnitus were cured successfully, however, the rare complication of facial nerve palsy due to reflux of Onyx® into the vasa nervorum occurred. This could be confirmed directly during surgery and by histological analysis.