Decoding of the results of ultrasonic dopplerography of vessels

Signs of subtotal stenosis and occlusion (narrowing of more than 85% or obstruction) of the internal carotid artery on the side of the lesion are as follows.

• Pathological sound phenomena. They differ depending on the degree of narrowing and the place of scoring - before stenosis, just above the site of constriction or when exiting it:
  • a sharp whistling sound;
  • a signal that resembles a "gull cry", or a phenomenon of vibration "mur-mur";
  • low-frequency weak damping signal up to a barely discernible "rustle".
• Expressed changes in the Doppler pattern from low-amplitude, diastolic to expanded at the base with a rounded or split vertex.
• The sharp asymmetry of the linear velocity of blood flow due to a decrease to 70-80% on the side of the lesion.
• A sharp drop in the linear velocity of the blood flow up to the disappearance of the signal from the ophthalmic artery on the side of the occluded carotid artery and / or the retrograde flow diminishing or disappearing upon compression of the homolateral external carotid artery.
• The presence of turbulence above or beyond the suspected zone of narrowing of the internal carotid artery.
• The disappearance of the freewheel window.
• The increase in the index of peripheral resistance is more than 0.8.
• Combination of stenosing lesions of several main arteries of the head.
• Possible poor tolerability of compression of the common carotid artery.

The accuracy of ultrasound dopplerography in the diagnosis of subtotal stenosis-occlusion of the internal carotid artery is 90-96%.

Signs of possible stenosis of the internal carotid artery from 70 to 85% on the side of the lesion are as follows.

• Asymmetry of the linear blood flow velocity up to 40% with bilateral dubbing of similar zones of the carotid artery.
• An increase in the linear velocity of the blood flow with the appearance of elements of turbulence over the zone of presumed stenosis of the internal carotid artery is lower in the bifurcation area and, if possible, higher than it.
• It is possible to increase the circulatory resistance index by more than 0.75.
• It is possible to increase the index of spectral expansion by more than 55%.
• Asymmetry of the linear velocity of the blood flow through the orbital artery to 30-40%.
• Bidirectional flow through the orbital artery on the side of stenosis is possible.
• It is also possible to influence the compression of the temporal branch of the homolateral external carotid artery with a decrease in the linear velocity of blood flow in the orbital artery on the side of carotid artery stenosis.

Naturally, the accuracy of recognition of constriction is 70 to 85% lower than for subtotal stenosis-occlusion, and ranges from 70 to 83%.

Even more modest are the results of using ultrasound dopplerography in attempts to diagnose narrowing of the vertebral arteries. Nevertheless, the following signs reveal.

• A sharp asymmetry of the linear velocity of blood flow more than 70% is characteristic for stenosis of the vertebral artery on the side of decreasing the linear velocity of blood flow.
• Whistling character of the signal with a significant change in the spectrogram on the side of stenosis of the vertebral artery.
• Frequent combination with carotid artery disease.

The accuracy of diagnosis of stenotic / occlusive lesions of the vertebral artery, according to different authors, ranges from 50 to 75%. A significantly higher percentage of correct results (up to 90%) is recorded with ultrasound Doppler diagnosis of subclavian steal syndrome.

[1], [2], [3], [4], [5], [6], [7]