Abstract A young man incurred a head injury with transiently impaired consciousness, multiple skull fractures, and monocular blindness. After 3 weeks he developed an intracerebral hemorrhage, which resolved without operative intervention. One week later he presented with massive epistaxis from a traumatic aneurysm of the right cavernous carotid artery, which extended into the sphenoid sinus. This was treated successfully by gradual occlusion of the carotid artery. Theories of the pathogenesis of these lesions as well as the rationale for treatment are discussed.