[Vascular emergencies of the head and neck].

The clinical manifestations of vascular lesions of the head and neck may be variable (hemorrhagic, ischemic, compressive). Diagnosis often is made at the time of acute presentation, but delayed manifestations, sometimes long after the initial presentation, should not be overlooked. Hemorrhagic manifestations are characterized by epistaxis, corresponding mainly to lesions of the nasal cavities but involvement of the internal carotid artery should be excluded (life threatening). In addition, some vascular malformations may lead to severe hemorrhage. Ischemic manifestations typically result from arterial dissection. A venous origin is also possible. Carotid-cavernous fistulas rarely lead to hemorrhagic or ischemic manifestations and tend to result in ocular manifestations, typically delayed and sometimes misleading.