Non invasive testing in carotid artery occlusive disease: the value of direct Doppler ultrasonography

Non invasive examination of carotid artery occlusive disease, as performed in our vascular laboratory, was compared to angiographic and operative findings in 65 patients (74 arteries). The sensitivity of carotid phonoangiography alone in detecting carotid artery stenosis was 73%. Ophthalmic flow direction was reversed in only 32% of stenosed arteries. Resistance index of directional Doppler sonography was high in only 15% of stenosed arteries. The most reliable part of the whole examination proved to be the direct "auscultation" of the carotid vessels in the neck. The overall sensitivity and specificity of this test was 88% and 64%, respectively; sensitivity being 94% for stenoses of over 50% in diameter and 55% for stenoses less than 50% in diameter. The major drawback of the test was its subjectiveness.