Angiographic variant in juvenile nasopharyngeal angiofibroma

A 17-year-old male with juvenile nasopharyngeal angiofibroma was found, on preoperative evaluation, to have a normal selective angiogram of the internal and external carotid artery system. Possible explanations for this variant include an atypical blood supply from the vertebral artery system, the thyrocervical trunks, or from an ascending pharyngeal artery that branched low from the external carotid artery.