High-energy blunt traumatic vertebro-vertebral arteriovenous fistula with retropharyngeal hematoma: A case report

Background: We report a rare case of high-energy blunt traumatic vertebro-vertebral arteriovenous fistula (VV-AVF) with retropharyngeal hematoma (RH) following C2 vertebral fracture after a traffic accident. Although there is currently no established guideline to treat blunt traumatic VV-AVF, effective transarterial embolization to sacrifice the parent artery succeeded in complete obliteration of the VV-AVF with no ischemic complications. Case presentation A 74-year-old woman injured in a traffic accident was transferred to our hospital by ambulance. On arrival, she complained of neck pain and headache. Her respiration and circulation were stable. Computed tomography (CT) revealed a slight subarachnoid hemorrhage, cervical spinal fracture (C2), rib fracture, and thoracic spinal compression fracture. Contrast-enhanced CT showed suspected dissection of her right vertebral artery (VA) at the C2 level. The next day, extravasation from her right vertebral artery at the C2 level was suspected on magnetic resonance angiography, and a thick RH was revealed on a T2-weighted magnetic resonance image. The angiographic study indicated a diagnosis of a high-flow VV-AVF at the C2 level. Transarterial embolization with coils was performed to sacrifice the parent artery, and n-butyl-2-cyanoacrylate injection significantly reduced flow through the fistula, which succeeded in completely obliterating the fistula at one month after the procedure. Conclusions VV-AVF caused by high-energy blunt trauma is extremely rare, but an upper cervical spine injury may trigger it, and RH may sometimes also occur. Transarterial coil embolization of the parent artery to completely obliterate the fistula is generally considered a reliable treatment in the acute stage. The current lack of a treatment guideline requires the accumulation of additional knowledge on the treatment of high-energy blunt traumatic VV-AVF.