What does it mean "normal vascular flow voids are present in the distal carotid and vertebral arteries, the basilar artery and the proximal anterior, ?

Normal arteries: Since the blood is moving during an MRI, the inside of the blood vessels appears to be a "flow void". This is the language used to report normal-appearing blood vessels.

Mri: That means on MRI there is a lack of signal in these areas which is normal. Flowing blood does not show up on normal mRI because it flows passed area before it has a chance to send back a signal