[Reliability of Doppler ultrasonography in relation to computerized digital angiography in patients with carotid bruit]

Abstract

The results of the carotid artery Doppler ultrasound examination were compared with those of digital subtraction angiography in 256 patients (187 men and 69 women) with carotid bruit. The hemodynamically significant stenoses of more than 50% and the occlusions in the 512 carotid arteries examined were considered and the sensibility, the specificity and the overall accuracy of the Doppler ultrasound examination were calculated. When a carotid stenosis was diagnosed a sensibility of 97%, a specificity of 95% and an overall accuracy of 96% was found, while, for the diagnosis of carotid occlusion, the extimated sensibility, specificity and overall accuracy was 95%. Therefore, the ability to recognize a normal or an occluded carotid artery was of 95% (we found 125 out of 131 normal carotid arteries and 52 out of 55 occluded carotid arteries), whereas a stenotic carotid artery was identified in the 97% of cases (316 out of 326 stenotic carotid arteries). When both diagnoses of carotid stenosis and carotid occlusion were considered together, the extimated sensibility, specificity and overall accuracy were of 98%, 95% and 98% respectively. So the probability of misdiagnosing was of 2% (we made 10 wrong diagnoses out of 512 carotid arteries examined).