As we get age, plaque builds up in our blood vessels. This is caused by smoking and other lifestyle choices like poor diet. One of the most common places for this to develop is at the carotid bifurcation.
Normally, our carotid artery comes off of our chest and up on each side in our neck. The artery then bifurcates, which means it splits into the external carotid artery, which gives blood to the face and the internal carotid artery, which supplies blood to the head. Where it bifurcates or splits is a common area for that plaque to build up. This plaque can create narrowing in a blood vessel, which impairs flow of blood going to the brain. It's also a site where blood can pool and form a clot. That clot can break off and travel into the head. If the clot blocks a blood vessel in the head, it can cause a stroke. This happens because blood isn’t getting to that part of the brain.
We can treat this carotid bifurcation disease in two ways. One way is to go from the inside and use a balloon to crack the plaque and essentially open it up, then lay a stent inside it to keep it open. Another option is treated with a surgery where an incision is made in the neck. The carotid artery is located, cut open, and plaque is removed. This is a definitive treatment because it removes the plaque, leaving a normal blood vessel.