Comparison of flow disturbances in small carotid atheroma using a multi-gate pulsed Doppler system and Doppler color...

The capacity of a multi-gate pulsed Doppler (MPD) system and Doppler color flow imaging (DCFI) for the evaluation of flow patterns was studied in 14 patients with 17 nonstenotic carotid plaques (luminal narrowing less than 40%). Plaque morphology was assessed by means of a high-resolution B-mode system with subsequent three-dimensional reconstruction of the lesion surface. MPD velocity profiles obtained proximally, centrally and distally to the plaque (51 analyses) were normal in 31 sites corresponding to 28 undisturbed and 3 turbulent flow patterns assessed by Doppler color flow imaging (90% specificity). Of the 10 irregular MPD flow profiles, DCFI detected turbulence in 7 (70% sensitivity). 10 asymmetric MPD waveforms without irregularities were normal in 7 and turbulent in 3 DCFI studies. These results suggest, that MPD is superior to DCFI for the detection of nonturbulent flow asymmetry nearby small carotid plaques. However, DCFI displays turbulence with a high specificity and reasonable sensitivity and visualizes the morphologic-hemodynamic interaction in carotid atherosclerosis simultaneously.