[Internal carotid artery dissection].

Arterial dissection results from bleeding into the vessel wall. Some cases are associated with cervical trauma or have evidence of an underlying vascular disease; many occur without any history of injury or detectable arterial disease. Among the cervical cephalic arteries, the extracranial segment of the internal carotid artery is the vessel most commonly involved; intracranial carotid dissections are much rare. Carotid dissection occurs predominantly in young or middle-aged adults and shows no sex predominance. Although clinical manifestations can be extremely diverse (from isolated headache to rapidly lethal stroke), the most common and suggestive syndrome associates "local" symptoms (such as head or neck pain, Horner's syndrome, pulsatile tinnitus or lower cranial nerves palsy) and delayed (up to several weeks) symptoms of cerebral ischaemia in the territory of the internal carotid artery territory. Dissection can be bilateral or associated with dissection of the vertebral artery. Angiography has long been considered the gold standard for the diagnosis. As this procedure carries a risk of cerebral complications, noninvasive diagnostic approaches such as magnetic resonance imaging and ultrasound have been developed and are increasingly used. The prognosis of carotid dissections depends on the presence and severity of ischaemic brain damage. Recurrent dissections seem extremely rare. Normalization or improvement of the vascular abnormalities during the subsequent weeks is frequent and is an excellent argument in favour of the diagnosis. Although no controlled trial has ever been performed, anticoagulant treatment is often used for a few months when the dissection involves the extracranial segment of the carotid artery. No standard treatment of intracranial carotid dissection has emerged.