This test uses ultrasound (sound waves) to show an image of the major arteries that travel up your neck to the brain.

Why do doctors want to see if these arteries are healthy? These arteries can develop thick cholesterol deposits, or "plaques." Occasionally, a fragment of plaque can break loose and float into the brain. This fragment is called an "embolus." It may cause a stroke or mini stroke (called a transient ischemic attack or TIA). A TIA causes temporary stroke symptoms but does not leave permanent damage.

The carotid Doppler test can find out if your arteries have cholesterol plaques. If you have a very large plaque, your doctor might talk to you about removing the plaque surgically to lower your risk for stroke. (A large plaque is one that narrows your artery to 40% or less of its expected diameter.) The surgery to clear plaque out is called "carotid endarterectomy."

The carotid Doppler test is painless and requires no preparation. The technician will slide a microphone-sized "wand" gently along the side of your neck to produce an ultrasound picture. Some lubricant may be used on your skin to allow the wand to slide freely. The does not puncture the skin or leave a mark.