David has an ultrasound of his common carotid arteries, which shows that his right common carotid artery is nearly 90 percent blocked. He wonders how the right side of his brain is getting enough blood if this artery is so occluded. What do you tell him?
David can have complete brain irrigation, thanks to the Willis polygon, is an arterial structure, which allows to redistribute blood flow, in case there is a process of ischemia and hypoxia.
