Spontaneous dissection in the common carotid artery--case report.

A 60-year-old female presented with a very rare spontaneous dissection in the common carotid artery manifesting as disturbance of consciousness and left dense hemiparesis immediately after swimming. Cerebral angiography showed complete obstruction of the right common carotid artery. Endarterectomy was performed to remove the subintimal thrombus and dissected intima. Blood flow was re-established 4 hours after onset of symptoms. Her disturbance of consciousness was resolved and left dense hemiparesis disappeared completely 12 hours after onset.