Uncommon ultrasound findings in traumatic extracranial vertebral artery dissection

We report a case of internal carotid artery dissection (ICAD) associated with contralateral vertebral artery dissection (VAD). The interest of this case is to discuss an unusual Doppler pattern manifesting by a spectrum of an alternating vertebral artery flow suggesting a hemodynamic contribution from the contralateral vertebral artery (VA) and a clear depiction of both antegrade (red) and retrograde (blue) flow within the false and true lumen of the VAD by color Duplex flow imaging.