A 21-year-old man presented with severe proptosis, chemosis, diplopia and an orbital bruit three weeks after a motor vehicle accident. The intraocular pressure was increased. The suspected diagnosis of a direct carotid-cavernous fistula (CCF) was confirmed by digital substraction arteriography. Placement of a covered stent in the internal carotid artery was performed with rapid resolution of the symptoms and normalization of the intraocular pressure. The epidemiology, pathogenesis, symptomatology, differential diagnosis, treatment and outcome of carotid-cavernous fistulas are discussed.