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Carotid artery stenosis - ultrasound criteria

Dr Bruno Di Muzio and Radswiki et al.

Ultrasound for internal carotid artery stenosis has become the first line examination in most cases, and images both the macroscopic appearance of the artery as well as flow characteristics.

normal
- ICA PSV is less than 125 cm/sec and no plaque or intimal thickening is visible sonographically.
- additional criteria include ICA / CCA PSV ratio < 2.0 and ICA EDV < 40 cm/sec.
< 50 % ICA stenosis
- ICA PSV is less than 125 cm/sec and plaque or intimal thickening is visible sonographically.
- additional criteria include ICA / CCA PSV ratio < 2.0 and ICA EDV < 40 cm/sec.
50 - 69 % ICA stenosis
- ICA PSV is 125 - 230 cm/sec and plaque is visible sonographically.
- additional criteria include ICA / CCA PSV ratio of 2.0 - 4.0 and ICA EDV of 40 - 100 cm/sec.
> / = 70 % ICA stenosis but less than near occlusion
- ICA PSV is greater than 230 cm / sec and visible plaque and luminal narrowing are seen at gray-scale and color Doppler US (the higher the Doppler parameters lie above the threshold of 230 cm/sec, the greater the likelihood of severe disease).
- additional criteria include ICA / CCA PSV ratio > 4 and ICA EDV > 100 cm/sec.
near occlusion of the ICA
- velocity parameters may not apply, since velocities may be high, low, or undetectable.
- diagnosis is established primarily by demonstrating a markedly narrowed lumen at colour or power Doppler US.
total occlusion of the ICA
- no detectable patent lumen at gray-scale US and no flow with spectral, power, and colour Doppler US.