A comparison of intra-arterial digital subtraction angiography with Doppler sonography in the assessment of carotid arterial stenosis.

A comparison is made of the use of selective intra-arterial subtraction angiography and doppler sonography in the assessment of disease in 206 carotid arteries. Maximal stenoses in each of the internal, external and common carotid arteries were recorded and compared using both modalities. In 93% of cases, arteries reported as normal ultrasonically were also found to be normal on angiography. However, agreement between the modalities in the assessment of severe stenoses was rather less at 79%. Overall agreement between the two modalities was good using statistical analysis (weighted Kappa). It is our view that ultrasound is reliable in normal vessels, but where significant disease is present the rate of error between the two modalities is too high to warrant omission of angiography.