An analysis on the diagnostic values of transcranial Doppler and angiography in transient ischemic attack.

The accuracy and diagnostic values of transcranial Doppler (TCD) in transient ischemic attack (TIA) caused by the stenosis or occlusion of intracranial or extracranial blood vessels were investigated. Of the 50 TIA patients receiving routine TCD examinations, 39 cases (77%) were diagnosed as having unilateral or bilateral stenosis or occlusion of MCA, ACA, siphon segment of internal carotid artery, which was furthermore confirmed by digital subtraction angiography (DSA) or MRA, 11 (22%) cases were normal. An analysis on the TCD findings of the flow patterns and hemodynamic changes of the stenotic or occluded blood vessels was made in comparison with that obtained by angiography. It was showed that angiography demonstrated 17 unilateral MCA stenosis, 47 bilateral multi-stenosis, 1 occlusion of the siphon segment of the internal carotid artery, while TCD revealed 17 unilateral stenosis, 64 bilateral stenosis, 1 occlusion respectively, with an accordance rate of 78.7%. It was concluded that the hemodynamic changes secondary to the stenosis of the basalcranial arteries, especially the moderate to severe stenosis or occlusion, might be an important risk factor for TIA. TCD examination achieved significant clinic values in the diagnosing of TIA.