Common carotid artery occlusion

Case contributed by Dr Bruno Di Muzio


Asymptomatic patient referred for routine examinations after angina.

Patient Data

Age: 67
Gender: Male

Carotid Artery Doppler Ultrasound

Grey-scale images of left CCA shows lumen to be filled with echogenic thrombus. Color imaging failed to show flow. Color Doppler image of left carotid bifurcation reveals both internal carotid artery (ICA) and external carotid artery (ECA) to be patent. Color Doppler images with spectral Doppler tracings show flow in ECA is reversed while flow in ICA remains anterograde.


CT angiography

Right carotid system without hemodynamically significant stenoses. Vertebral arteries without hemodynamically significant changes.

Total occlusion of the left common carotid artery (CCA) from its origin in the aortic arch to the carotid bulb. Retrograde flow in the left external carotid artery (ECA) weakly refill the internal carotid artery (ICA) on this side.

Case Discussion

In about 25% of CCA occlusion, the ICA and ECA will remain patent. For this to occur, flow in one of the vessels must be reversed. In almost all cases, like on this one, it will be the ECA, with its rich supply of potential collaterals, that reverses and provides blood to the ICA. This interesting phenomenon produces one vessel displayed in red and the other in blue on color Doppler assessment. 

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Case information

rID: 17800
Published: 14th May 2012
Last edited: 21st May 2019
System: Vascular
Inclusion in quiz mode: Excluded

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