Brainstem edema caused by traumatic carotid-cavernous fistula: A case report and review of the literature.

Brainstem edema caused by traumatic carotid-cavernous fistula (TCCF) is rare, and there is little information available regarding its clinical characteristics. The present report describes the case of a 51-year-old man with TCCF, who presented with right exophthalmos and intracranial bruit for 1 week. One month prior to admission at hospital, he fractured the frontal and ethmoid sinuses. Digital subtraction angiography confirmed the diagnosis of TCCF, and magnetic resonance imaging (MRI) suggested edema on the right side of the pons. Five days after admission, the patient exhibited left hemiparesis, and MRI revealed aggravation of the brainstem edema. Following treatment with transarterial balloon embolization, the clinical symptoms, including hemiparesis, were relieved; at the 1-month follow-up, the brain edema had disappeared. The patient was normal at the 6-month follow-up. Following the report of the present case, we reviewed six additional cases previously reported in the literature and discussed the potential mechanisms of TCCF-associated brainstem edema. We conclude that occlusion of the superior petrosal sinus may contribute to brainstem edema caused by TCCF. Relief of the brainstem edema and brainstem edema-associated clinical symptoms can be achieved with transarterial coil or balloon embolization of the TCCF to reduce the drainage pressure in the brainstem veins.