Spontaneous dissection of both extracranial internal carotid arteries.

Neurological examination and Doppler sonography of a 50-year-old patient were suggestive of a spontaneous dissection of the left internal carotid artery (left-sided headaches, amaurosis fugax, Horner's syndrome and hemispheric stroke). Four-vessel angiogram performed several days after the onset of the symptoms showed dissection of both extracranial carotid arteries, more pronounced on right side where the dissection was clinically asymptomatic. Angiogram follow-up demonstrated a recanalization of both carotid arteries. A review of 15 other documented reports indicates that bilateral internal carotid dissection is usually associated with fibromuscular dysplasia. A large majority of cases does not clinically differ from unilateral carotid artery dissection.