How It Feels
There is normally no discomfort involved
with having a Doppler ultrasound test. The gel may feel cold when it is put on
your skin unless it is first warmed to body temperature. If your blood pressure
is taken during the test, you will feel pressure when the blood pressure cuff
There are no known risks associated with a
Doppler ultrasound test. This test will not harm a fetus.
ultrasound test uses reflected sound waves to see how
blood flows through a blood vessel.
There are no findings of
significant narrowing or other abnormality in any of the arteries
There is no evidence of a clot
in any of the veins examined. The size and position of veins are
Normal blood flow is found in
the blood vessels that supply oxygen and nutrients to a
For continuous wave Doppler or
duplex Doppler, differences in blood flow between the right and left sides of
the body may be heard. At the exact location where an artery is blocked or
narrowed, the sound may be high-pitched or turbulent. Blockage (such as from a
blood clot), an
aneurysm, or narrowing of a blood vessel may be
detected. The speed of blood flow may be compared to standard values to find
out the amount of blockage or narrowing of the blood vessel.
A duplex Doppler ultrasound
graph may show irregular flow that means a blocked or narrowed blood
A color Doppler image may show
a blocked or narrowed blood vessel or an aneurysm.
In the veins, a blood clot may
be indicated if blood flow does not change in response to breathing or does not
increase in response to either a compression maneuver or
Valsalva maneuver. Incomplete blockage of a vein by a
blood clot may be seen on color Doppler or during a compression
Abnormal veins, such as
varicose veins, are seen.
Blood flow through the blood
vessels that supply oxygen and nutrients to a fetus is abnormally increased or
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- Bones above the area being studied or gas in
- Not being able to remain still during the
- Irregular heart rhythms
(arrhythmias) or heart disease, which may cause changes in blood flow patterns
even though the blood vessels are not abnormal.
- Having a cold arm
or leg. Blood flow through that limb may be slowed.
- Having an open
wound in the area that needs to be viewed.