Area reduction in carotid stenosis - Measurement with colour Doppler energy coded duplex sonography.

Aim: In patients with atherosclerotic extracranial internal carotid artery (ICA-) stenosis the diagnostic value of colour Doppler energy (CDE)-coded d uplexsonography was compared to three other methods: continuous wave (cw) D oppler peak systolic frequency (pF), pulsed wave (pw) Doppler peak systolic velocity (pV), and intraarterial digital subtraction angiography. Methods: In 58 patients who suffered from 60 moderate to severe ICA stenoses, B-mod e sonography combined with CDE-coded duplex sonography was applied to measu re the extent of the stenosis by determining the residual lumen width. Resu lts were correlated to pF and pV and with various angiographic indices. Res ults: The determined Values of the degree of stenosis were correlated to th e measurement of pV (r = 0.441, p < 0.01), but not to pF (r = 0.122, n.s.). The best correlation to angiography was obtained when the linear ICA diame ter was compared to the distal common carotid artery (common carotid artery index) (r = 0.214, n.s.). Sensitivity, specificity and diagnostic accuracy were comparable to the different frequency-based measurements, but the pos itive predictive Value was lower. Conclusions: Determination of the degree of stenosis based on CDE alone is not reliable enough to allow correct diag nosis of severe carotid artery stenosis. In combination with the peak frequ ency method is's diagnostic value could be improved. This requires verifica tion in a separate study.