Carotid Doppler Test


A carotid Doppler test is used to detect narrowing of the arteries in the neck (the carotid arteries) that supply blood to the brain. During this test, these arteries are visualized using high-frequency sound waves (ultrasound) for evidence of plaque (blockages). Analysis of the blood flow through the arteries by Doppler ultrasound permits accurate measurement of the degree of narrowing of the blood vessel. Ultrasound is not harmful in any way.


  1. The patient is asked to lie flat on an examination table, with his or her head on a pillow, slightly turned away from the side being examined.
  2. A water-soluble gel is applied to the transducer (the part of the ultrasound machine that produces and receives sound waves). The transducer is placed on either side of the neck to examine the anatomy and flow in the arteries.
  3. The patient will feel only a slight pressure as the transducer is moved around the neck.
  4. The patient may hear sounds during the test. This is due to the flow of blood that is amplified by the ultrasound machine; this occurs normally during the test.
  5. The entire examination takes approximately 30 to 40 minutes. Digital recordings are taken by the sonographer.
  6. The completed study is reviewed by a cardiologist and a report is sent to the patient’s doctor.

Special Instructions

The patient should bring along a list of current medications. Fasting (not eating) before the test is not required.