The carotid arteries are the two main arteries that supply blood flow to the brain. Blockages in these arteries can sometimes lead to strokes.  In order to evaluate the condition of these arteries a carotid ultrasound is performed.  This will detect blockages in the arteries as well as evaluate blood flow through these blockages.  This allows your physician to determine whether or not a significant blockage is present.  This will also evaluate the need for surgery.