Abstract
BACKGROUND: This report describes an ethmoidal dural arteriovenous fistula (DAVF) presenting with the unusual symptom of recurrent epistaxis and successfully treated with selective transarterial embolization through the infraorbital artery (IOA), which is the first time this route was used to the best of the authors' knowledge, and reviews the literature focusing on the anatomical consideration of ethmoidal DAVFs causing epistaxis and its treatment approaches. OBSERVATIONS: A 70-year-old man experienced recurrent intractable epistaxis that bled like a faucet turned on. Cerebral angiography revealed an ethmoidal DAVF supplied by the left anterior ethmoidal artery, both sphenopalatine arteries, both IOAs, and the right angular artery, which drained directly into the frontal cortical veins with a tortuous arterialized ectasia. Microaneurysms around the fistulous location where multiple feeding arteries converge were demonstrated and considered the likely source of the epistaxis. The fistula was completely occluded using transarterial Onyx embolization through the IOA, a branch of the internal maxillary artery. No further epistaxis appeared. LESSONS: Although extremely rare, ethmoidal DAVFs should be included in the differential diagnosis of recurrent epistaxis. Ethmoidal DAVFs with bleeding sources in the ethmoid sinus and nasal cavity may cause epistaxis. It is important to properly diagnose and treat ethmoidal DAVFs presenting with epistaxis on the basis of a comprehensive anatomical understanding of extensive extracranial-extracranial and extracranial-intracranial anastomoses.