What is a Doppler ultrasound?
A Doppler ultrasound is a noninvasive imaging test that uses sound waves to show blood moving through the blood vessels. Regular ultrasounds also use sound waves to create images of internal body structures, but they cannot show blood flow.
Doppler ultrasound works by measuring sound waves that are reflected off moving objects, such as red blood cells that’s why this is known as the Doppler effect.
There are different types of Doppler ultrasound tests. They include:
- Colour Doppler– This type of Doppler uses a computer to change the sound waves into different colors and these computer-generated colors show the speed and direction of blood flow in real-time.
- Power Doppler is a newer type of color Doppler. It can provide more detail on blood flow than standard color Doppler. But it cannot show the direction of blood flow, which may be important in some cases.
- Spectral Doppler- This test displays blood flow information on a graph instead of in color images. It can help show how much your blood vessels are blocked.
- Duplex Doppler- This test uses standard ultrasound to take pictures of your blood vessels and organs. A computer then converts the images into a graph, as in Doppler spectroscopy.
- Continuous Wave Doppler- In this test, sound waves are sent and received continuously. Allows more accurate measurement of blood flow at faster rates.
In which conditions Doppler Ultrasound is used?
Doppler ultrasound tests are used to help healthcare providers, determine if you have a condition that reduces or blocks blood flow. It may also be used to help diagnose certain heart conditions. The test is often used for –
- Cardiac function check- It’s often done along with an electrocardiogram, which is a test that measures electrical signals in the heart.
- Look for a blockage in the blood flow. Blockage of blood flow in the legs can lead to a condition called deep vein thrombosis (DVT).
- Check for damage to blood vessels and defects in the structure of the heart.
- Look for narrowing of the blood vessels. Narrow arteries in your arms and legs may mean you have a condition called peripheral arterial disease (PAD). Narrowed arteries in your neck could mean you have a condition called carotid stenosis.
- Check your blood flow after surgery.
- Check the normal blood flow of a pregnant woman and her unborn baby.
Read About: Chest X-Ray
What are the symptoms in which Doppler Ultrasound is used?
Doppler ultrasound is used for the symptoms of reduced blood flow or heart disease. Symptoms, depending on the severity of the problem. Some of the common conditions and symptoms of blood flowing are listed below.
Symptoms of peripheral arterial disease (PAD) include:
- Numbness or weakness in the legs.
- Painful cramps in the hips or calf muscles when walking or climbing stairs.
- If you are feeling cold in the lower leg or foot.
- Discoloration and/or sheen of leg skin.
Symptoms of heart problems include:
- Breathing difficulties
- Swelling in the legs, feet, and/or abdomen
Doppler ultrasound is also needed if :
- Having a stroke- After a stroke, the healthcare provider may order a special type of Doppler test, called a transcranial Doppler, to check blood flow to the brain.
- If anyone has been injured in his blood vessels.
- If anyone getting treatment for a disorder of blood flow.
- In the case of a pregnant woman and the doctor thinks that the unborn baby may have a problem with blood flow. The doctor may suspect a problem if the unborn baby is smaller than it should be at this stage of the pregnancy or have some suspected health problems. They include sickle cell disease or preeclampsia, a type of high blood pressure that affects pregnant women.
What happens during a Doppler ultrasound?
Doppler ultrasound generally includes the following steps:
- You will lie on a table, revealing the area of your body being examined.
- The health care provider will apply a special gel to the skin in that area.
- The technician will wave a wand-like device, called a transducer, over the area.
- The device sends sound waves to your body.
- The movement of blood cells causes a change in the pitch/echo of the sound waves. You may hear wheezing or pulse-like sounds during the procedure.
- The waves are recorded and converted into images or graphs on the screen.
- After the test is completed, the provider will clean the gel from your body.
- This very test takes between 30 and 60 minutes to complete.
How to prepare for this test?
Generally, a person does not need to prepare for a Doppler ultrasound.
However, if they are smokers, the doctor may ask them to refrain from smoking for a few hours before the procedure. Smoking can narrow the blood vessels, which can distort the readings.
What are the results of the Doppler Ultrasound?
Doppler ultrasound results help doctors determine the health of the veins and arteries.
Normal results indicate that the images do not show problems such as blockage or narrowing of the blood vessels.
If the technician finds a suspected indication, this may indicate:
- Blood clot.
- A blockage in a vein or artery, which may be the result of a buildup of cholesterol, for example
- Coronary artery spasm, involves the narrowing of an artery in the heart, possibly due to stress.
Certain factors can distort the results of a Doppler ultrasound, such as:
- Cardiovascular disease
- Smoking before ultrasound
The technician does not discuss the results with the person. He sends the results to the doctor, who will answer any questions. If any symptoms have been detected then the doctor will decide the next course of action.
( Disclaimer: Information provided in this piece of article is purely for educational purposes only. All results must be clinically correlated with the patient’s data to make an accurate diagnosis.)