Cervicocephalic arterial dissection

: The authors review the clinical and neuroradiological features of cervicocephalic arterial dissection, which is occasionally seen in young adults, with special reference to the differences in the region of occurrence of these lesions between patients in Western countries and Japan. In Western countries, the cervical internal carotid artery is the most common site of occurrence of these lesions; however, in Japan, these lesions have been frequently reported to occure in the intracranial vertebral artery. Most clinical manifestations of cervical arterial dissection are non-hemorrhagic events such as headaches associated with arterial dissection or cerebral ischemia caused by a distal embolism following thrombus formation in the cervical lesion. On the other hand, a subarachnoid hemorrhage and cerebral infarction are frequently observed in intracranial arterial dissections. Non-invasive procedures, including MR imaging, are useful for demonstrating characteristic features of this condition such as the presence of an intimal flap or a double lumen, and for monitoring the chronological changes in the lesions, which may regress spontaneously. Since the pathological mechanisms underlying the progression and / or the regression of this condition are still unknown, the clinical evidence indicating the optimal therapeutic strategies has not yet been reported. Nevertheless, conservative therapy, including antithrombotic treatment, is widely used for the treatment of non-hemorrhagic lesions, which generally results in good clinical outcomes. Further, surgical intervention is essential for the treatment of lesions with a subarachnoid hemorrhage to prevent fatal rebleeding, and it is also required for the treatment of certain non-hemorrhagic lesions. Recent advancements in surgical procedures, especially endovascular treatments, may therefore be helpful in the management of similar complicated vascular conditions.