The clinical course, transcranial Doppler ultrasound (TCD) findings, and angiographic outcome are reported for a patient with a traumatic carotid artery dissection. Transient asymmetrical decreased middle cerebral artery blood flow velocities led to the suspicion of an internal carotid artery (ICA) stenosis. Duplex scanning and angiography subsequently demonstrated an extracranial traumatic ICA dissection in combination with a traumatic saccular aneurysm. These data imply that TCD monitoring has a potential to diagnose not only well established complications of neurotrauma, such as vasospasm and intracranial hypertension, but may also suggest the presence of traumatic extracranial carotid obstructions.