A Doppler ultrasound is a type of ultrasound imaging test that is used to estimate how well the blood flows through your blood vessels. It also looks at the rate of blood flow (the volume of blood flowing through your blood vessels) and the speed of your blood flow. Doppler ultrasounds can be used to examine the blood flow in your:· Arteries (blood vessels that carry oxygenated blood away from your heart and lungs to the rest of your body).· Veins (blood vessels that carry deoxygenated blood from your body to your heart and lungs to receive more oxygen).Doppler ultrasounds can be used to assess the blood flow in multiple areas of your body, including your: · Heart· Arms and legs · Neck· Brain· Abdomen · Organs (following organ transplant surgery)
A Doppler ultrasound assesses the blood flow in your veins and arteries. It can be used to detect a number of health conditions that affect your blood vessels, including conditions that affect the amount of blood flowing through your vessels, the speed of blood flow and the direction your blood is flowing in different areas of your body. A Doppler ultrasound can be used to detect a number of health conditions, including:· Blood clots. · Defects in your heart valves. · Congenital heart disease. · Narrowing in the arteries (stenosis).· Blockages in the arteries (arterial occlusion).· Venous insufficiency (where the valves in your leg veins don’t function correctly, causing blood or other fluids to collect in your legs).· Decreased circulation in your legs.· Aneurysms (bulging in the artery wall).A Doppler ultrasound can also be used to detect abnormalities in the structure of your arteries.
A Doppler ultrasound is a painless, non-invasive procedure. A small ultrasound probe emits high-frequency sound waves that bounce off the red blood cells that flow through your blood vessels. When the sound waves bounce off the blood cells, they create echoes which are picked up by the ultrasound probe. The echoes vary, depending on whether the blood cells are moving towards the sound waves or away from the sound waves. The ultra sound probe measures these echoes and creates pictures or graphs that can be analysed.
There are multiple different types of Doppler ultrasounds, including:· Colour Doppler ultrasounds: This ultrasound uses a special computer to change the echoes into different colours. The different colours correspond to different rates of blood flow and the different directions the blood is flowing. · Power Doppler ultrasounds: This ultrasound is used to detect smaller blood vessels and slower rates of blood flow. However, power Dopplers can’t detect the direction of the blood flow.· Spectral Doppler ultrasounds: This ultrasound assesses how blocked the blood vessel is. The information gathered from the ultrasound is organised into a graph. There are two types, a pulsed wave Doppler and a continuous wave Doppler. · Duplex Doppler ultrasound: This ultrasound uses moving images to assess blood flow. The images are turned into a graph.The different types of Doppler ultrasounds are used for different purposes and to collect different information.
There are multiple reasons why your doctor may recommend a Doppler ultrasound, including:· You are experiencing symptoms consistent with abnormal blood flow (e.g. numbness, weakness or swelling).· You are at higher risk of a stroke.· You have experienced a transient ischemic attack(TIA).· You experience an injury to a blood vessel.· You have high blood pressure with the suspected cause being a blocked artery in your kidneys.· To assess the effectiveness of treatment (for conditions relating to your blood vessels). You may also be offered a Doppler ultrasound during pregnancy.
Because Doppler ultrasounds can be done on different areas of the body, the exact process can vary. Unless instructed otherwise, you can eat, drink and take medication as usual on the day of your appointment. However, if necessary, the clinic will give you specific instructions regarding medication. You may be asked not to smoke or use nicotine products on the day of your ultrasound. At the start of the ultrasound, you may be asked to remove an item of clothing to allow easier access to the area that is being scanned. For example, if you are having an ultrasound on your leg, you may need to wear shorts or change into a medical gown. You will be asked to lie down in a specific position and a special gel will be applied to your skin. The probe will be moved slowly around the intended area. The images or graphs will appear on the computer screen for the medical professional to look at and analyse.
A Doppler ultrasound scan usually takes between 30 and 60minutes. The time can vary depending on the amount of preparation required, the area being scanned and the type of Doppler ultrasound taking place.
As well as Doppler ultrasounds, there are a number of other tests that use ultrasounds, including:· Echocardiogram (also known as heart echo scan).· Carotid ultrasound. · Endoscopic ultrasound.· Lung ultrasound. · Internal ultrasound. · Intravascular ultrasound.
