Spectral Doppler waveform of the normal Common carotid artery (CCA):

The above images (Rt. CCA) show moderately broad systolic peaks and moderate diastolic flow in diastole. The peak systolic velocity (PSV or V-max) is also in a range between that of the ICA and ECA. This is the typical appearance of the waveform of the CCA. Normal PSV for the CCA is usually less than 100cms./sec. (In this case, the PSV= 94 cms./sec.). The PSV in the CCA increases towards its proximal part (ie: towards the aorta).

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