Non-invasive assessment of carotid arteries: a comparison of techniques used in two laboratories

Fifty-one patients were examined non-invasively in two different laboratories and underwent angiography for carotid artery disease. Results of the two examinations and angiography were compared. In one laboratory continuous wave Doppler ultrasonography of the accessible extracranial arteries was used; in the other laboratory spectral analysis of the Doppler signals and angioscan imaging of the bifurcation was carried out. Accuracy of the two examinations (when compared with angiography) were similar for stenoses of more than 50%; spectral analysis and angioscan were better than continuous wave Doppler in detection of less than 50% stenoses.