[Comparative studies of the diagnostic value of various parameters of Doppler frequency spectral analysis of the carotid artery].

Angiographic findings in 94 internal carotid arteries were compared to different parameters of Doppler frequency spectral analysis: systolic and late diastolic peak frequency of the internal carotid artery, ratio of the internal and common carotid systolic and late diastolic peak frequency, spectral broadening as calculated by subtracting internal carotid mean frequency from systolic or late diastolic peak frequency respectively. The normal values were calculated as the 97.5% confidence interval of these parameters in angiographically normal vessels. Specificity, sensitivity, overall accuracy and negative as well as positive predictive value were also calculated. The diagnostic value of the systolic peak frequency of the internal carotid artery proved not to be exceeded by any of the other parameters.