Evaluation of the color coded Doppler ultrasound in detecting carotid bifurcation disease

The color coded continuous wave doppler ultrasound was compared with angiography in 201 arteries, 83 with greater than 50% diameter stenosis and 118 with less than 50% stenosis. Overall accuracy in identifying hemodynamically significant (greater than 50% diameter stenosis) was 87% in the presence of peak velocities greater than 5000 Hz and a blue color coded image. Negative predictive value was 94.5%. False positives were mainly due to the presence of severe external carotid stenosis and increased flow due to contralateral carotid occlusion. Within the limitations of the test being an indirect method, it is a reliable screening method for detecting hemodynamically significant carotid artery disease.