Transient ischemic attacks: Pathophysiology and medical management.

There is substantial evidence to support the concept that most transient ischemic attacks (TIAs) are caused by microemboli that originate in areas of atherosclerosis in the blood vessels of the neck. TIA's are important risk factors in the development of stroke. The most common clinical features of TIAs caused by carotid insufficiency are hemianesthesia and hemiparesis; other symptoms in these cases include headache, dysphasia, and visual field distrubance. By far the most common clinical manifestation of vertebrobasilar insufficiency is vertigo.