Doppler Ultrasonography Health Article

Definition

Doppler ultrasonography, also called Doppler ultrasound, is a noninvasive diagnostic procedure that uses an ultrasound scanner to convert sound waves into images of blood flow in body tissue and organs. Doppler ultrasonography does not use ionizing radiation and is used for a variety of clinical applications.

Purpose

Doppler ultrasonography is used during an ultra-sound examination to assess the direction, velocity, and turbulence of blood flow. It is frequently used in cardiac and vascular scanning to evaluate blood flow and diagnose abnormalities in flow. Cardiac applications include the detection of heart valve problems, the determination of arterial vessel narrowing (stenosis) or blockage, the diagnosis of congenital cardiac defects, and the evaluation of damage following myocardial infarction (heart attack). Vascular applications include the work-up of stroke patients, the assessment of blood flow in the major abdominal arteries, and the evaluation of vessels in the arms, legs, and neck. Vascular conditions that can be diagnosed using Doppler ultrasonography include deep vein thrombosis (DVT), a blocked carotid artery, blood clots, tumors with vascular involvement, and abdominal aortic aneurysm. Doppler ultasonography can also be used to determine whether a patient is a candidate for a surgical or other interventional procedure, such as vascular grafting, or it can be used during and after cardiac and

vascular surgical procedures to assess blood flow and the success of the procedure. In obstetric ultrasound, Doppler ultrasonography is used to check fetal cardiac activity.

Doppler ultrasonography can be performed in a hospital radiology or cardiology department, a hospital vascular laboratory, at the patient's bedside, in the emergency department, in an operating room, or in an outpatient imaging center, depending on the patient's medical condition. Doppler ultrasonography is a noninvasive, safer, and faster alternative to x-ray angiography, which involves radiation exposure, the injection of a contrast dye, and catheterization of blood vessels, although ultrasound may not yield images that are as detailed as those from x rays during catheterization.

A new device introduced in 2000 combines Doppler ultrasonography with endoscopy. The Doppler ultrasound scanner is interfaced with an endoscopy system, and the Doppler ultrasound images can be simultaneously displayed with the endoscopic images on one monitor, like a picture-in-picture display. Clinical applications include the evaluation of ulcers and hemorrhaging, vascular abnormalities of the intestinal tract, and enlarged vessels in the digestive tract, as well as assessment during endoscopic surgical procedures.