Detection of occlusive disease of the carotid artery with continuous wave Doppler spectral analysis.

The accuracy of Doppler spectral analysis for diagnosing stenoses of the carotid artery was evaluated in this study. Two hundred and five patients were examined, using a 4 megahertz continuous wave Doppler velocity meter and a real-time frequency analyzer. By a comparison of the results of arteriography, peak Doppler frequencies of greater than 3.8 kilohertz were diagnostic of internal carotid artery stenoses having residual lumen diameters of 3.2 millimeters, or less, with a sensitivity rate of, 91 per cent and a specificity rate of 92 per cent. Spectral broadening, evaluated by subjective grading, yielded similar results.