Fig. 1.

The arteries and veins used for measurements of cerebral blood flow and flow in the internal jugular veins. The small white arrows point at the internal carotid arteries, the large white arrows point at the vertebral arteries, and the black arrows point at the internal jugular veins. White color represents flow into the cranial cavity, and black color represents flow out from the cranial cavity. The intensity of the color represents the flow value. Note the difference in both size and flow between the left and the right internal jugular veins