Spectral Doppler waveforms of the normal ICA (internal carotid artery):

The Doppler images above show the spectral waveform of the normal ICA (Internal carotid artery-Rt.). The systolic peak in the ICA is broader than the ECA or even the CCA. Also, note the high (and persistent) diastolic flow. The normal PSV (Vmax in our image), ranges from55 to 88 cms./sec. in the ICA. This is true for the post bulbar (part distal to the carotid bulb) part of the ICA. (In our case the PSV or Vmax = 68 cms./sec).

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