[Vascular murmurs in arteriosclerotic stenosis of the internal carotid artery].

As many as 152 patients with atherosclerotic lesions of the internal carotid arteries (ICA) of varying degree verified on angiography were examined by phonoangiography. A well-defined relationship was noted between the presence, intensity and frequency characteristics of vascular murmur on the one hand and the intensity of stenoses in both ICA on the other one. Murmur signals were not found in atherosclerotic lesions of the walls of the ICA without impairment of the vascular lumen in the area of the carotid arteries on the neck and in the area of the orbits. Weak carotid murmur occurred with a 20% decrease of the area of the total lumen of both ICA. Strong carotid murmur with high-frequency signals occurred in summary stenosis amounting to over 50% of the lumen of both ICA on the side of more gross stenosis or on the side of the ICA stenosis in occlusion of the opposite vessel. In patients with fairly gross stenosis or occlusion of one ICA and stenosis of the intracranial part of the other ICA, phonography of the orbital area on the side of stenosis recorded high-frequency signals on the spectrogram, in the range from 300 to 1000 Hz.