How Venous Doppler Ultrasound Works
- Posted on: Jun 9 2017
One of the exams most helpful to a vein specialist is venous Doppler ultrasound. Vascular surgeons and other vein doctors often use it to rule out certain conditions, to better visualize varicose veins, and to determine the nature of a patient’s vein disease.
Why Vein Doctors Use Venous Doppler
A Doppler ultrasound exam assesses how blood flows through blood vessels. This noninvasive outpatient test is more sophisticated than regular ultrasound, which utilizes sound waves to create images but is unable to depict blood flow.
The Mayo Clinic notes that Doppler exams have many uses. They help vein specialists and other physicians diagnose and evaluate conditions such as:
- Defective leg vein valves that could cause venous insufficiency
- Blood clots
- Aneurysms or bulging arteries
- Narrowing of any arteries, such as carotid artery stenosis in the neck
- Arterial occlusions or blocked arteries
- Defects in heart valves
- Peripheral artery disease
- Congenital heart disease
Vein doctors often use this test to monitor the effectiveness of vein treatments. According to MedlinePlus, smoking tobacco could alter exam results. A normal finding means that there is no sign of clots, narrowing, or closure in blood vessels and that blood flow in the arteries is normal.
How This Technology Works
This specialized ultrasound measures both the speed and the direction of blood cells traveling through blood vessels. Movement results in a pitch change of reflected sound waves known as the Doppler effect, according to the Radiological Society of North America, Inc.
A computer captures and process these sounds. The technology then creates images that are graphs or color pictures that depict blood flow characteristics.
Patients are able to see several pieces of equipment. Scanners include a console with a computer and electronic components, a video screen to display images, and a hand-held transducer resembling a microphone.
As the staff member performing the procedure passes the transducer over the each targeted area of the patient’s body, the equipment emits high-frequency sound waves. After these waves have penetrated the body, the transducer listens for echoes from body parts similar to the way sonar operates on boats.
The resulting ultrasound image displays immediately on the video screen. Its characteristics are the result of loudness, pitch, and the length of time required for the signal to return from the area examined to the transducer. Imaging also takes into consideration the body’s structure and the makeup of body tissue through which sound waves have traveled.
Staff members normally position patients face-up on a movable table for this exam. Gel applied to the targeted area helps eliminate air pockets that might block sound waves from entering the body. The individual performing the test sweeps the transducer over various body points, angling the device as necessary to better visualize certain areas.
Doppler ultrasound exams are painless. Most take about half an hour.
Posted in: Vein Treatment