Carotid Ultrasound is used to scan the two carotid arteries in the neck to provide images of these important blood vessels and of blood flowing through them. Its primary application is to detect narrowing or blockage of the carotid artery indicative of an elevated risk of stroke.
In addition to screening for this risk, a carotid ultrasound can aid in assessing patients with high blood pressure and those whose neck area presents unusual sounds when examined with a stethoscope. This procedure is also performed on patients about to undergo coronary artery bypass surgery, on patients with diabetes, on those with elevated blood cholesterol and on those for whom a family history of heart disease or stroke is present. The procedure can reveal an area of clotted blood known as a hematoma. It can assess whether surgery undertaken to restore carotid blood flow was successful, and is useful in verifying the placement of a stent inserted to keep the carotid artery open.
Limitations of Carotid Ultrasound
A carotid ultrasound is sometimes performed on children to ascertain blood flow and identify those with sickle cell disease who may be at a higher risk of stroke. It can also reveal other anomalies present in blood vessels and the lymphatic system. In children and adults, the success of carotid sonography imaging may be limited if a surgical scar or wound dressing is present or if the size or shape of the neck obscures access to the artery by the transducer probe. Hardened calcium deposits in the artery wall may interfere with imaging, and smaller amounts of soft plaque may not be detectable to any extent.
In addition, ultrasound cannot evaluate the uppermost part of the carotid artery as it travel through bone into the skull. A CT scan or MRI may be necessary for a complete evaluation.