Doppler diagnosis in cases of acute stroke.

Ultrasound techniques are employed increasingly for the evaluation of patients with cerebrovascular disease. We determined the accuracy of carotid Doppler ultrasonography, which incorporated spectral analysis and periorbital directional Doppler assessment, by comparison with conventional or digital-subtraction arteriography in 93 patients (186 vessels). We also reviewed our experience with the Doppler technique in consecutive patients who were admitted to hospital with established carotid-territory stroke. The Doppler technique had a sensitivity of 93% and a specificity of 97% as a screening test for the presence of carotid stenosis, and a high level of precision. The arteriography rate in patients with completed stroke was 40% before the introduction of Doppler ultrasonography but decreased to 24% after its introduction, and to 16% in the last 100 cases. The proportion of cases in whom an underlying cause for stroke could not be identified decreased from 31% of cases to 21% of cases. Extracranial carotid stenosis was implicated in only 22 of the last 100 patients with carotid-territory stroke. Doppler ultrasonography is a valuable diagnostic tool in patients with completed stroke. It aids in the selection of patients for arteriography and provides clues to the pathogenesis of stroke in patients in whom arteriography is inappropriate.