Congenital arteriovenous fistulas supplied by a single branch of the maxillary artery.

We report four cases (two children, two adults) of congenital arteriovenous fistula supplied by a single large (pterygoid) branch of the second part of the maxillary artery deep to the parotid gland and mandible, with emphasis on the angiographic findings, therapeutic implications, and cause, with a review of the literature. Awareness of a predilection of congenital arteriovenous fistulas for this site, excellent-quality selective angiography, and careful attention to flow patterns help make the correct diagnosis. Endovascular balloon occlusion is the preferred treatment.