[Cerebral artery dissection].

The main symptom of arterial dissection is intense acute unilateral headache. The pain is commonly located around the eye, in the temple or the front with a carotid artery dissection [CAD] and in the posterior neck and occiput with a vertebral artery dissection [VAD]. Transient or persistent cerebral ischemic symptoms are similarly frequent but usually occur later in the time course. Horner's syndrome indicating a lesion of perivascular sympathetic fibres represents the third leading symptom and occurs in more than one third of the patients. Compression of local structures such as lower nerve or radicular palsies is rare. This constellation of symptoms in a young patient without vascular risk factors should rise suspicion of a dissection, in particular, if there is a preceding 'trivial' trauma. Characteristic features on Doppler/duplex sonography provide the diagnosis of dissection in almost all CAD and the majority of VAD. MRI demonstrating the mural hematoma allows reliable confirmation of the suspected diagnosis. Angiography is necessary only in selected cases, more often in VAD than in CAD. Brain infarction may be prevented, if premonitory symptoms, which occur in 60 to 80% of the patients, are recognized as such. Therefore, if there is clinical and sonographic suspicion of CAD or VAD, anticoagulation therapy with heparin should should be started before other imaging procedures finally prove the diagnosis. Because immediate anticoagulation may prevent cerebral embolism, this treatment strategy seems appropriate, although its efficacy has not been established by a controlled study. Anticoagulation should be continued until resolution of the dissection.