Where is the site of stenosis to explain the right CCA and ICA ultrasound findings?
Brachiocephalic trunk.
The right common carotid and internal carotid arteries demonstrate a widened waveform and low peak systolic velocity (parvus et tardus pattern).
There is bidirectional ('to-and-fro') flow within the right vertebral artery (second image sequence).
Elevated peak systolic velocites within the left internal carotid artery (192 cm/s maximally) indicating 50-69% stenosis.