Ouantification of Carotid Arterial Disease by Doppler Ultrasound

Abstract

Chanaes in the Doppler spectrum arising from disturbed flow, particularly in the carotid arteries, are difficult to assess in a reliable manner. This paper describes a method of quantification based on extractinq the instantaneous maximum and a mean spectral waveforms. The degree of disturbed flow is estimated from a spectral broadening index (maximum-mean/maximum) . Both the maximum and mean are obtained diqitally and the spectral broadening index waveform is computed in real time. Experimental results are shown using an in vitro model that closely approximates the carotid flow conditions. The index, when measured at peak SYStole a t points just beyond a stenosis correlate quite well w ith the percent area stenosis.